WO2023081804A1

WO2023081804A1 - Platelet derivative compositions, and methods of making and using such compositions

Info

Publication number: WO2023081804A1
Application number: PCT/US2022/079280
Authority: WO
Inventors: Joshua Donald Montgomery; Braden Carl Ishler; Stephen Edward AMOS; Keith Andrew MOSKOWITZ; Amber Nicole LEE; Rafael Jorda; Glen Michael Fitzpatrick; Michael Alexander Mathews
Original assignee: Cellphire, Inc.
Priority date: 2021-11-04
Filing date: 2022-11-04
Publication date: 2023-05-11

Abstract

Provided herein are materials and methods for the preparation of blood products. In some aspects, provided herein are compositions that include populations of platelet derivatives, including freeze-dried platelet derivatives, methods of producing the same, as well as methods of using the same to treat a subject. Such platelet derivatives have improved properties, as disclosed herein.

Description

PLATELET DERIVATIVE COMPOSITIONS, AND METHODS OF MAKING AND USING

SUCH COMPOSITIONS

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Application Serial No. 63/275,937, filed on November 4, 2021, U.S. Provisional Application Serial No. 63/276,420, filed on November 5, 2021, U.S. Provisional Application Serial No. 63/264,226, filed on November 17, 2021, U.S. Provisional Application Serial No. 63/264,227, filed on November 17, 2021, U.S. Application Serial No. 17/673,773, filed on February 16, 2022, International Application No. PCT/US22/16866, filed on February 17, 2022, U.S. Provisional Application Serial No. 63/364,620, filed on May 12, 2022, U.S. Provisional Application Serial No. 63/371,849, filed on August 18, 2022, and U.S. Provisional Application Serial No. 63/376,986, filed on September 23, 2022. Each of the aforementioned applications is incorporated herein by reference in its entirety.

STATEMENT OF GOVERNMENT INTEREST

[0002] This invention was made with government support under Contract No. HHS0100201300021 awarded by the Biomedical Advanced Research and Development Authority (BARDA) of the U.S. Department of Health and Human Services. The government has certain rights in the invention.

TECHNICAL FIELD

[0003] The present disclosure generally relates to blood products, including those containing platelet derivatives, methods of producing such blood products, and methods of treating a subject using such blood products.

BACKGROUND

[0004] Blood is a complex mixture of numerous components. In general, blood can be described as comprising four main parts: red blood cells, white blood cells, platelets, and plasma. The first three are cellular or cell-like components, whereas the fourth (plasma) is a liquid component comprising a wide and variable mixture of salts, proteins, and other factors necessary for numerous bodily functions. The components of blood can be separated from each other by various methods. In general, differential centrifugation is most commonly used currently to separate the different components of blood based on size and, in some applications, density. [0005] Inactivated platelets, which are also commonly referred to as thrombocytes, are small, often irregularly-shaped (e.g., discoidal or ovoidal) megakaryocyte-derived components of blood that are involved in the clotting process. They aid in protecting the body from excessive blood loss due not only to trauma or injury, but to normal physiological activity as well. Platelets are considered crucial in normal hemostasis, providing the first line of defense against blood escaping from injured blood vessels. Platelets generally function by adhering to the lining of broken blood vessels, in the process becoming activated, changing to an amorphous shape, and interacting with components of the clotting system that are present in plasma or are released by the platelets themselves or other components of the blood. Purified platelets have found use in treating subjects with low platelet count (thrombocytopenia) and abnormal platelet function (thrombasthenia). Concentrated platelets are often used to control bleeding after injury or during acquired platelet function defects or deficiencies, for example those occurring during surgery and those due to the presence of platelet inhibitors.

SUMMARY

[0006] Provided herein, at least in part, are blood products (e.g., a composition comprising platelets or platelet derivatives (e.g., thrombosomes)) with reduced levels of free protein (e g., antibodies (e.g., Human Leukocyte Antigen (HLA) antibodies, or Human Neutrophil Antigen (HNA) antibodies)) and methods of producing and using the same. Accordingly, provided herein are compositions including platelets, and/or, in illustrative embodiments, platelet derivatives.

[0007] Implementations can have one or more of the following features. The composition can have a solid, such as a powder form. The composition can be in an aqueous medium. The protein concentration of the aqueous medium can be less than 30% of the protein concentration of donor apheresis plasma. The aqueous medium can have a concentration of human leukocyte antigen (HLA) Class 1 antibodies that is less than 30% of the human leukocyte antigen (HLA) Class I antibody concentration in donor apheresis plasma. The aqueous medium can have a concentration of human leukocyte antigen (HLA) Class II antibodies that is less than 30% of the human leukocyte antigen (HLA) Class II antibody concentration in donor apheresis plasma. The aqueous medium can have a concentration of human neutrophil antigen (HNA) antibodies that is less than 30% of the HNA antibody concentration in donor apheresis plasma. The protein concentration can be less than 10% of the protein concentration of donor apheresis plasma. The aqueous medium can have a concentration of human HLA Class I antibodies that is less than 10% of the HLA Class I antibody concentration in donor apheresis plasma. The aqueous medium can have a concentration of human HLA Class II antibodies that is less than 10% of the HLA Class II antibody concentration in donor apheresis plasma. The aqueous medium can have a concentration of human HNA

2

RECTIFIED SHEET (RULE 91 ) ISA/EP antibodies that is less than 10% of the HNA antibody concentration in donor apheresis plasma. The protein concentration can be less than 5% of the protein concentration of donor apheresis plasma. The aqueous medium can have a concentration of human HLA Class I antibodies that is less than 5% of the HLA Class I antibody concentration in donor apheresis plasma. The aqueous medium can have a concentration of human HLA Class II antibodies that is less than 5% of the HLA Class II antibody concentration in donor apheresis plasma. The aqueous medium can have a concentration of human HNA antibodies that is less than 5% of the HNA antibody concentration in donor apheresis plasma. The protein concentration can be less than 3% of the protein concentration of donor apheresis plasma. The aqueous medium can be a concentration of human HLA Class I antibodies that is less than 3% of the HLA Class I antibody concentration in donor apheresis plasma. The aqueous medium can have a concentration of human HLA Class II antibodies that is less than 3% of the HLA Class II antibody concentration in donor apheresis plasma. The aqueous medium can have a concentration of human HNA antibodies that is less than 3% of the HNA antibody concentration in donor apheresis plasma. The protein concentration can be less than 1% of the protein concentration of donor apheresis plasma. The aqueous medium can have a concentration of human HLA Class I antibodies that is less than 1% of the HLA Class I antibody concentration in donor apheresis plasma. The aqueous medium can have a concentration of human HLA Class II antibodies that is less than 1% of the HLA Class II antibody concentration in donor apheresis plasma. The aqueous medium can have a concentration of human HNA antibodies that is less than 1% of the HNA antibody concentration in donor apheresis plasma. The protein concentration can be determined by absorbance at 280 nanometers (nm) with a path length of 0.5 cm. In some embodiments, the absorbance at 280 nm can be less than 1.7 AU. In some embodiments, the absorbance at 280 nm can be less than 1.66 AU. In some embodiments, the absorbance at 280 nm can be less than 1.6 AU. In some embodiments, the platelet count can be at least 200 x 10³ platelets/pL. In some embodiments, the platelet count can be at least 2250 x 10³ platelets/pL. In some embodiments, the composition can have an erythrocyte count less than 0.2 x 10⁶ erythrocytes/pL. In some embodiments, the composition can further include erythrocytes. In some embodiments, the erythrocyte count can be less than 0.2 x 10⁶ crythrocytcs/pL. The composition can be negative for HLA Class I antibodies based on a regulatory agency approved test. The composition can be negative for HLA Class II antibodies based on a regulatory agency approved test. The composition can be negative for HNA antibodies based on a regulatory agency approved test. The percentage of beads positive for an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, Class II HLAs, or HNAs, respectively, can be less than 5%. The percentage of beads positive for an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, Class II HLAs, or HNAs, respectively, can be less than 3%. The percentage of beads positive for an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, Class II HLAs, or HNAs, respectively, can be less than 1%. The percentage of beads positive for HLA Class I antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, can be less than 5%. The percentage of beads positive for HLA Class I antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, can be less than 3%. The percentage of beads positive for HLA Class I antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, can be less than 1%. The percentage of beads positive for HLA Class II antibodies, as determined for the composition by flow cytometry using beads coated with Class II HLAs can be less than 5%. The percentage of beads positive for HLA Class II antibodies, as determined for the composition by flow cytometry using beads coated with Class II HLAs, can be less than 3%. The percentage of beads positive for HLA Class II antibodies, as determined for the composition by flow cytometry using beads coated with Class II HLAs, can be less than 1%. The percentage of beads positive for HNA antibodies, as determined for the composition by flow cytometry using beads coated with HNAs can be less than 5%. The percentage of beads positive for HNA antibodies, as determined for the composition by flow cytometry using beads coated with HNAs, can be less than 3%. The percentage of beads positive for HNAs, as determined for the composition by flow cytometry using beads coated with HNAs, can be less than 1%. The aqueous medium can further include a buffering agent, a base, a loading agent, optionally a salt, and optionally at least one organic solvent. The buffering agent can be HEPES (4- (2 -hydroxyethyl)-! -piperazineethanesulfonic acid). The base can be sodium bicarbonate. The loading agent can be a monosaccharide, a polysaccharide, or a combination thereof. The monosaccharide can be selected from the group consisting of sucrose, maltose, trehalose, glucose, mannose, and xylose. The monosaccharide can be trehalose. The polysaccharide can be polysucrose. The salt can be sodium chloride, potassium chloride, or a combination thereof. The organic solvent can be selected from the group consisting of ethanol, acetic acid, acetone, acetonitrile, dimethylformamide, dimethyl sulfoxide, dioxane, methanol, n-propanol, isopropanol, tetrahydrofuran (THF), N-methyl pyrrolidone, dimethylacetamide (DMAC), and combinations thereof. The composition can be prepared by a process including tangential flow filtration (TFF) of a starting material comprising platelets, centrifugation of a starting material comprising platelets, or a combination thereof. The percentage of beads positive for an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, Class II HLAs, or HNAs, respectively, can be reduced by at least 50% as compared to a similar

4

RECTIFIED SHEET (RULE 91 ) ISA/EP composition not prepared by a process including tangential flow filtration of a blood product composition, centrifugation of a blood product composition, or a combination thereof. The percentage of beads positive for an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, Class II HLAs, or HNAs, respectively, can be reduced by at least 75% as compared to a similar composition not prepared by a process including tangential flow filtration of a blood product composition, centrifugation of a blood product composition, or a combination thereof. The percentage of beads positive for an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, Class II HLAs, or HNAs, respectively, can be reduced by at least 90% as compared to a similar composition not prepared by a process including tangential flow filtration of a blood product composition, centrifugation of a blood product composition, or a combination thereof. The percentage of beads positive for an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, Class II HLAs, or HNAs, respectively, can be reduced by at least 95% as compared to a similar composition not prepared by a process including tangential flow filtration of a blood product composition, centrifugation of a blood product composition, or a combination thereof. The starting material can be (a) positive for HLA Class I antibodies based on a regulatory agency approved test, (b) positive for HLA Class II antibodies based on a regulatory agency approved test, (c) positive for HNA antibodies based on a regulatory agency approved test, or (d) one or more of (a), (b), and (c). The starting material can have a protein concentration of about 60 to about 80 mg/ml. The starting material can include donor blood product. The donor blood product can be pooled donor blood product. The starting material can include donor apheresis material. The TFF can include concentrating. The TFF can include diafiltering. The diafiltering can include diafiltering with at least two diavolumes. The TFF can include buffer exchange. The TFF can be carried out using a membrane with pore size of about 0.2 pm to about 1 pm. The TFF can be carried out using a membrane with pore size of about 0.2 pm to about 0.45 pm. The TFF can be performed at a temperature of about 20 °C to about 37 °C. The TFF can be carried out until the absorbance at 280 nm of the aqueous medium is less than 50% of the absorbance at 280 nm of the starting material, using a path length of 0.5 cm. The TFF can be carried out until the absorbance at 280 nm of the aqueous medium is less than 30% of the absorbance at 280 nm of the starting material, using a path length of 0.5 cm. The TFF can be carried out until the absorbance at 280 nm of the aqueous medium is less than 10% of the absorbance at 280 nm of the starting material, using a path length of 0.5 cm. The TFF can be carried out until the absorbance at 280 nm of the aqueous medium is less than 5% of the absorbance at 280 nm of the starting material, using a path length of 0.5 cm. The TFF can be carried out until the absorbance at 280 nm of the aqueous medium is less than 3% of the absorbance at 280 nm of the starting material, using a path length of 0.5 cm. The TFF can be carried out until the absorbance at 280 nm of the aqueous medium is less than 1% of the absorbance at 280 nm of the starting material, using a path length of 0.5 cm. The TFF can be carried out until the absorbance at 280 nm of the aqueous medium is less than 1.70 AU, using a path length of 0.5 cm. The TFF can be carried out until the absorbance at 280 nm of the aqueous medium is less than 1.66 AU, using a path length of 0.5 cm. The TFF can be carried out until the absorbance at 280 nm of the aqueous medium is less than 1.60 AU, using a path length of 0.5 cm. The TFF can be carried out until the platelet concentration is at least about 2000 x 10³ platelets/pU. The TFF can be carried out until the platelet concentration is at least about 2250 x 10³ platelets/pU. The TFF can include buffer exchange into a buffer comprising a buffering agent, a base, a loading agent, optionally a salt, and optionally at least one organic solvent. The buffering agent can be HEPES (4-(2-hydroxyethyl)- 1 -piperazineethanesulfonic acid). The base can be sodium bicarbonate. The loading agent can be a monosaccharide, a polysaccharide, or a combination thereof. The monosaccharide can be selected from the group consisting of sucrose, maltose, trehalose, glucose, mannose, and xylose. The monosaccharide can be trehalose. The polysaccharide can be polysucrose. The salt can be sodium chloride, potassium chloride, or a combination thereof. The organic solvent can be selected from the group consisting of ethanol, acetic acid, acetone, acetonitrile, dimethylformamide, dimethyl sulfoxide, dioxane, methanol, n- propanol, isopropanol, tetrahydrofuran (THF), N-methyl pyrrolidone, dimethylacetamide (DMAC), and combinations thereof. The centrifugation can include centrifugation at 1400 x g to about 1550 x g. The centrifugation can include centrifugation at 1450 x g to about 1500 x g. The process can lack centrifugation of a composition comprising platelets. The composition can include less than 5.0% (by scattering intensity) microparticles. The composition can include less than 4.5% (by scattering intensity) microparticles. The composition can include less than 4.0% (by scattering intensity) microparticles. The composition can include less than 3.5% (by scattering intensity) microparticles. The platelets or platelet derivatives can have a CD41 percent positivity of at least 55%. The platelets or platelet derivatives can have a CD41 percent positivity of at least 60%. The platelets or platelet derivatives can have a CD41 percent positivity of at least 65%. The platelets or platelet derivatives can have a CD42 percent positivity of at least 80%. The platelets or platelet derivatives can have a CD42 percent positivity of at least 85%. The platelets or platelet derivatives can have a CD42 percent positivity of at least 90%. The platelets or platelet derivatives can retain at least about 10% of the lactate dehydrogenase activity of donor apheresis platelets. The platelets or platelet derivatives can retain at least about 15% of the lactate dehydrogenase activity of donor apheresis platelets. The platelets or platelet derivatives can retain at least about 20% of the lactate dehydrogenase activity of donor apheresis platelets. The platelets or platelet derivatives can have an annexin V percent positivity of at least 70%. The platelets or platelet derivatives can have an annexin V percent positivity of at least 75%. The platelets or platelet derivatives can have an annexin V percent positivity of at least 80%. The platelets or platelet derivatives can have CD47 percent positivity of at least 8%. The platelets or platelet derivatives can have CD47 percent positivity of at least 10%. The platelets or platelet derivatives can have CD47 percent positivity of at least 15%. The platelets or platelet derivatives can have CD47 percent positivity of at least 20%. The platelets or platelet derivatives can have CD62 percent positivity of at least 80%. The platelets or platelet derivatives can have CD62 percent positivity of at least 82%. The platelets or platelet derivatives can have CD62 percent positivity of at least 85%. The platelets or platelet derivatives can have CD62 percent positivity of at least 90%. The platelets or platelet derivatives can have fibrinogen associated with the cell membrane. The aqueous medium can have a lactate concentration of less than 2.0 mmol/L. The aqueous medium can have a lactate concentration of less than 1.5 mmol/L. The aqueous medium can have a lactate concentration of about 0.4 to about 1.3 mmol/L. The aqueous medium can have a lactate concentration of about 0.5 to about 1.0 mmol/L. The platelet derivatives can include thrombosomes.

[0008] Also provided herein is a process for preparing a composition comprising platelets, or in illustrative embodiments, platelet derivatives and an aqueous medium, the process including tangential flow filtration (TFF) of a starting material comprising platelets, centrifugation of a starting material comprising platelets, or a combination thereof, wherein the aqueous medium has a protein concentration less than 50% of the protein concentration of donor apheresis plasma.

[0009] Implementations can include one or more of the following features. The starting material can be (a) positive for HLA Class I antibodies based on a regulatory agency approved test, (b) positive for HLA Class II antibodies based on a regulatory agency approved test, (c) positive for HNA antibodies based on a regulatory agency approved test, or (d) one or more of a), b), and c). The starting material can have a protein concentration of about 60 to about 80 mg/mL. The starting material can include donor blood product. The donor blood product can be pooled donor blood product. The starting material can include donor apheresis material. The TFF can include concentrating. The TFF can include diafiltering. The diafiltration can include diafiltering with at least two diavolumes. The TFF can include buffer exchange. The TFF can be carried out using a membrane with pore size of about 0.2 pm to about 1 pm. The TFF can be carried out using a membrane with pore size of about 0.2 pm to about 0.45 pm. The TFF can be performed at a temperature of about 20 °C to about 37 °C. The TFF can be carried out until the absorbance at 280 nm of the aqueous medium is less than 50% of the absorbance at 280 nm of the starting material, using a path length of 0.5 cm. The TFF is carried out until the absorbance at 280 nm of the aqueous medium is less than 30% of the absorbance at 280 nm of the starting material, using a path length of 0.5 cm. The TFF can be carried out until the absorbance at 280 nm of the aqueous medium is less than

7

RECTIFIED SHEET (RULE 91 ) ISA/EP

carried out until the absorbance at 280 nm of the aqueous medium is less than 5% of the absorbance at 280 nm of the starting material, using a path length of 0.5 cm. The TFF can be carried out until the absorbance at 280 nm of the aqueous medium is less than 3% of the absorbance at 280 nm of the starting material, using a path length of 0.5 cm. The TFF can be carried out until the absorbance at 280 nm of the aqueous medium is less than 1% of the absorbance at 280 nm of the starting material, using a path length of 0.5 cm. The TFF can be carried out until the absorbance at 280 nm of the aqueous medium is less than 1.70 AU, using a path length of 0.5 cm. The TFF can be carried out until the absorbance at 280 nm of the aqueous medium is less than 1.66 AU, using a path length of 0.5 cm. The TFF can be carried out until the absorbance at 280 nm of the aqueous medium is less than 1.60 AU, using a path length of 0.5 cm. The TFF can be carried out until the platelet concentration is at least about 2000 x 10³ platelets/pU. The TFF can be carried out until the platelet concentration is at least about 2250 x 10³ platelets/pU. The TFF can include buffer exchange into a buffer comprising a buffering agent, a base, a loading agent, optionally a salt, and optionally at least one organic solvent. The buffering agent can be HEPES (4-(2-hydroxyethyl)- 1 -piperazineethanesulfonic acid). The base can be sodium bicarbonate. The loading agent can be a monosaccharide, a polysaccharide, or a combination thereof. The monosaccharide can be selected from the group consisting of sucrose, maltose, trehalose, glucose, mannose, and xylose. The monosaccharide can be trehalose. The polysaccharide can be polysucrose. The salt can be sodium chloride, potassium chloride, or a combination thereof. The organic solvent can be selected from the group consisting of ethanol, acetic acid, acetone, acetonitrile, dimethylformamide, dimethyl sulfoxide, dioxane, methanol, n- propanol, isopropanol, tetrahydrofuran (THF), N-methyl pyrrolidone, dimethylacetamide (DMAC), and combinations thereof. The centrifugation can include centrifugation at 1400 x g to about 1550 x g. The centrifugation can include centrifugation at 1450 x g to about 1500 x g. The process can lack centrifugation of a composition comprising platelets. The percentage of beads positive for an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, Class II HLAs, or HNAs, respectively, can be reduced by at least 50% as compared to a similar composition not prepared by a process including tangential flow fdtration of a blood product composition, centrifugation of a blood product composition, or a combination thereof. The percentage of beads positive for an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, Class II HLAs, or HNAs, respectively, can be reduced by at least 75% as compared to a similar composition not prepared by a process including tangential flow fdtration of a blood product composition, centrifugation of a blood product composition, or a combination thereof. The percentage of beads positive for an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, Class II HLAs, or HNAs, respectively, can be reduced by at least 90% as compared to a similar composition not prepared by a process including tangential flow fdtration of a blood product composition, centrifugation of a blood product composition, or a combination thereof. The percentage of beads positive for an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, Class II HLAs, or HNAs, respectively, can be reduced by at least 95% as compared to a similar composition not prepared by a process including tangential flow fdtration of a blood product composition, centrifugation of a blood product composition, or a combination thereof. The protein concentration can be less than 30% of the protein concentration of donor apheresis plasma. The aqueous medium can have a concentration of human leukocyte antigen (HLA) Class I antibodies that is less than 30% of the human leukocyte antigen (HLA) Class I antibody concentration in donor apheresis plasma. The aqueous medium can have a concentration of human leukocyte antigen (HLA) Class II antibodies that is less than 30% of the human leukocyte antigen (HLA) Class II antibody concentration in donor apheresis plasma. The aqueous medium can have a concentration of human neutrophil antigen (HNA) antibodies that is less than 30% of the HNA antibody concentration in donor apheresis plasma. The protein concentration can be less than 10% of the protein concentration of donor apheresis plasma. The aqueous medium can have a concentration of human HLA Class I antibodies that is less than 10% of the HLA Class I antibody concentration in donor apheresis plasma. The aqueous medium can have a concentration of human HLA Class II antibodies that is less than 10% of the HLA Class II antibody concentration in donor apheresis plasma. The aqueous medium can have a concentration of human HNA antibodies that is less than 10% of the HNA antibody concentration in donor apheresis plasma. The protein concentration can be less than 5% of the protein concentration of donor apheresis plasma. The aqueous medium can have a concentration of human HLA Class I antibodies that is less than 5% of the HLA Class I antibody concentration in donor apheresis plasma. The aqueous medium can have a concentration of human HLA Class II antibodies that is less than 5% of the HLA Class II antibody concentration in donor apheresis plasma. The aqueous medium can have a concentration of human HNA antibodies that is less than 5% of the HNA antibody concentration in donor apheresis plasma. The protein concentration can be less than 3% of the protein concentration of donor apheresis plasma. The aqueous medium can have a concentration of human HLA Class I antibodies that is less than 3% of the HLA Class I antibody concentration in donor apheresis plasma. The aqueous medium can have a concentration of human HLA Class II antibodies that is less than 3% of the HLA Class II antibody concentration in donor apheresis plasma. The aqueous medium can have a concentration of human HNA antibodies that is less than 3% of the HNA antibody concentration in donor apheresis plasma. The protein concentration can be less than 1% of the protein concentration of donor apheresis plasma. The aqueous medium can have a concentration of human HLA Class I antibodies that is less than 1% of the HLA Class I antibody concentration in donor apheresis plasma. The aqueous medium can have a concentration of human HLA Class II antibodies that is less than 1% of the HLA Class II antibody concentration in donor apheresis plasma. The aqueous medium can have a concentration of human HNA antibodies that is less than 1% of the HNA antibody concentration in donor apheresis plasma. The composition can be negative for HLA Class I antibodies based on a regulatory agency approved test. The composition can be negative for HLA Class II antibodies based on a regulatory agency approved test. The composition can be negative for HNA antibodies based on a regulatory agency approved test. The percentage of beads positive for an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, Class II HLAs, or HNAs, respectively, can be less than 5%. The percentage of beads positive for an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, Class II HLAs, or HNAs, respectively, can be less than 3%. The percentage of beads positive for an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, Class II HLAs, or HNAs, respectively, can be less than 1%. The percentage of beads positive for HLA Class I antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, can be less than 5%. The percentage of beads positive for HLA Class I antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, can be less than 3%. The percentage of beads positive for HLA Class I antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, can be less than 1%. The percentage of beads positive for HLA Class II antibodies, as determined for the composition by flow cytometry using beads coated with Class II HLAs can be less than 5%. The percentage of beads positive for HLA Class II antibodies, as determined for the composition by flow cytometry using beads coated with Class II HLAs, can be less than 3%. The percentage of beads positive for HLA Class II antibodies, as determined for the composition by flow cytometry using beads coated with Class II HLAs, can be less than 1%. The percentage of beads positive for HNA antibodies, as determined for the composition by flow cytometry using beads coated with HNAs, can be less than 5%. The percentage of beads positive for HNA antibodies, as determined for the composition by flow cytometry using beads coated with HNAs, can be less than 3%. The percentage of beads positive for HNAs, as determined for the composition by flow cytometry using beads coated with HNAs, can be less than 1%. The process of any one of claims 125- 199, wherein the composition comprises less than 5.0% (by scattering intensity) microparticles. The composition can include less than 4.5% (by scattering intensity) microparticles. The composition can include less than 4.0% (by scattering intensity) microparticles. The composition can include less than 3.5% (by scattering intensity) microparticles. The platelets or platelet derivatives can have a CD41 percent positivity of at least 55%. The platelets or platelet derivatives can have a CD41 percent positivity of at least 60%. The platelets or platelet derivatives can have a CD41 percent positivity of at least 65%. The platelets or platelet derivatives can have a CD42 percent positivity of at least 80%. The platelets or platelet derivatives can have a CD42 percent positivity of at least 85%. The platelets or platelet derivatives can have a CD42 percent positivity of at least 90%. The platelets or platelet derivatives can retain at least about 10% of the lactate dehydrogenase activity of donor apheresis platelets. The platelets or platelet derivatives can retain at least about 15% of the lactate dehydrogenase activity of donor apheresis platelets. The platelets or platelet derivatives can retain at least about 20% of the lactate dehydrogenase activity of donor apheresis platelets. The platelets or platelet derivatives can have an annexin V percent positivity of at least 70%. The platelets or platelet derivatives can have an annexin V percent positivity of at least 75%. The platelets or platelet derivatives can have an annexin V percent positivity of at least 80%. The platelets or platelet derivatives can have CD47 percent positivity of at least 8%. The platelets or platelet derivatives can have CD47 percent positivity of at least 10%. The platelets or platelet derivatives can have CD47 percent positivity of at least 15%. The platelets or platelet derivatives can have CD47 percent positivity of at least 20%. The platelets or platelet derivatives can have CD62 percent positivity of at least 80%. The platelets or platelet derivatives can have CD62 percent positivity of at least 82%. The platelets or platelet derivatives can have CD62 percent positivity of at least 85%. The platelets or platelet derivatives can have CD62 percent positivity of at least 90%. The platelets or platelet derivatives can have fibrinogen associated with the cell membrane. The aqueous medium can have a lactate concentration of less than 2.0 mmol/L. The aqueous medium can have a lactate concentration of less than 1.5 mmol/L. The aqueous medium can have a lactate concentration of about 0.4 to about 1.3 mmol/L. The aqueous medium can have a lactate concentration of about 0.5 to about 1.0 mmol/L. The platelet derivatives can include thrombosomes. The process can further include a pathogen reduction step. The pathogen reduction step can precede TFF. The process can further include lyophilizing the composition comprising platelets or platelet derivatives. The process can further include thermally treating the composition comprising platelets or platelet derivatives.

[00010] Also provided herein is a composition including platelets and an aqueous medium prepared by any of the processes described herein. [00011] Also provided herein is a process for preparing freeze-dried platelets, including (a) preparing a composition comprising platelets and an aqueous medium using any of the processes described herein and (b) freeze-drying the composition comprising platelets and the aqueous medium.

[00012] Also provided herein is a composition comprising freeze-dried platelets, prepared by any of the processes described herein.

[00013] Also provided herein is a method for preparing a composition comprising platelets or platelet derivatives and an aqueous medium, the method including diluting a starting material comprising platelets to form a diluted starting material, concentrating the platelets to about 2250 x 10³ cells/pL (±250 x 10³) to form a concentrated platelet composition, and washing the concentrated platelet composition with at least 2 diavolumes (DV) of the preparation agent to form a TFF-treated composition.

[00014] Implementations can include one or more of the following features. Diluting can include diluting with an approximately equal weight (±10%) of the preparation agent. The method can further include a pathogen reduction step. The pathogen reduction step can occur before diluting the starting material. The residual plasma percentage can be less than about 15% relative plasma (as determined by plasma protein content). Following washing, if the concentration of the cells in the TFF-treated composition is not about 2000 x 10³ cells/pL (±300 x 10³), the method can further include diluting the preparation agent or can be concentrated to fall within this range. The method can further include lyophilizing the TFF-treated composition to form a lyophilized composition. The method can further include treating the lyophilized composition at about 80 °C for about 24 hours.

[00015] Also provided herein is a composition comprising platelets or platelet derivatives prepared by any of the methods described herein.

[00016] The materials and methods described herein can provide several advantages. For example, they can allow for the collection of otherwise deferred donors and reduce the competition for apheresis materials.

[00017] Further details regarding aspects and embodiments of the present disclosure are provided throughout this patent application. The preceding paragraphs in this Summary section is not an exhaustive list of aspects and embodiments disclosed herein. Sections and section headers are for ease of reading and are not intended to limit combinations of disclosure, such as methods, compositions, and kits or functional elements therein across sections. DESCRIPTION OF THE DRAWINGS

[00018] Figure 1A shows initial gate placement for identification of Class I and Class II HLA FLOWPRA™ beads in PBS using side scattering vs. forward scattering.

[00019] Figure IB shows initial gate placement for identification of Class I and Class II HLA FLOWPRA™ beads in PBS using phycoerythrin fluorescence vs. forward scattering.

[00020] Figure 2A shows an exemplary FITC-H histogram of FLOWPRA™ beads in PBS, supplier platelet-poor plasma (PPP) (in triplicate), and donor platelet-poor plasma gated on Class I HLA (in triplicate).

[00021] Figure 2B shows an exemplary FITC-H histogram of FLOWPRA™ beads in PBS, supplier platelet-poor plasma (PPP) (in triplicate), and donor platelet-poor plasma gated on Class II HLA (in triplicate).

[00022] Figure 2C shows an exemplary FITC-H histogram of FLOWPRA™ beads in PBS, supplier platelet-poor plasma (PPP) (single data set), and donor platelet-poor plasma gated on Class I HLA (single data set).

[00023] Figure 2D shows an exemplary FITC-H histogram of FLOWPRA™ beads in PBS, supplier platelet-poor plasma (PPP) (single data set), and donor platelet-poor plasma gated on Class II HLA (single data set).

[00024] Figure 3 A shows an exemplary FITC-H histogram of FLOWPRA™ beads in George King PPP gated on Class I HLA.

[00025] Figure 3B shows an exemplary FITC-H histogram of FLOWPRA™ beads in George King PPP gated on Class II HLA.

[00026] Figure 4A shows an exemplary FITC-H histogram of FLOWPRA™ beads in Donor 1 PPP gated on Class I HLA.

[00027] Figure 4B shows an exemplary FITC-H histogram of FLOWPRA™ beads in Donor 1 PPP gated on Class II HLA.

[00028] Figure 5A shows an exemplary FITC-H histogram of FLOWPRA™ beads in Donor 2 PPP gated on Class I HLA. [00029] Figure 5B shows an exemplary FITC-H histogram of FLOWPRA™ beads in Donor 2 PPP gated on Class II HLA.

[00030] Figure 6A shows an exemplary FITC-H histogram of FLOWPRA™ beads in Donor 3 PPP gated on Class I HLA.

[00031 ] Figure 6B shows an exemplary FITC-H histogram of FLOWPRA™ beads in Donor 3 PPP gated on Class II HLA.

[00032] Figure 7A shows an exemplary FITC-H histogram of FLOWPRA™ beads in Donor 4 PPP gated on Class I HLA.

[00033] Figure 7B shows an exemplary FITC-H histogram of FLOWPRA™ beads in Donor 4 PPP gated on Class II HLA.

[00034] Figure 8 A shows an exemplary FITC-H histogram of FLOWPRA™ beads in Donor 5 PPP gated on Class I HLA.

[00035] Figure 8B shows an exemplary FITC-H histogram of FLOWPRA™ beads in Donor 5 PPP gated on Class II HLA.

[00036] Figure 9A shows an exemplary FITC-H histogram of FLOWPRA™ beads in Donor 6 PPP gated on Class I HLA.

[00037] Figure 9B shows an exemplary FITC-H histogram of FLOWPRA™ beads in Donor 6 PPP gated on Class II HLA.

[00038] Figure 10A shows an exemplary FITC-H histogram of FLOWPRA™ beads in Donor 7 PPP gated on Class I HLA.

[00039] Figure 10B shows an exemplary FITC-H histogram of FLOWPRA™ beads in Donor 7 PPP gated on Class II HLA.

[00040] Figure 11 A shows an exemplary FITC-H histogram of FLOWPRA™ beads pooled Donor PPP gated on Class I HLA.

[00041] Figure 1 IB shows an exemplary FITC-H histogram of FLOWPRA™ beads pooled Donor PPP gated on Class II HLA. [00042] Figure 12A shows an exemplary FITC-H histogram of FLOWPRA™ beads pooled Donor PPP gated on Class I HLA following tangential flow fdtration (TFF) to 50% (by absorbance at 280 nm) retained plasma protein.

[00043] Figure 12B shows an exemplary FITC-H histogram of FLOWPRA™ beads pooled Donor PPP gated on Class II HLA following tangential flow fdtration (TFF) to 50% (by absorbance at 280 nm) retained plasma protein.

[00044] Figure 13A shows an exemplary FITC-H histogram of FLOWPRA™ beads pooled Donor PPP gated on Class I HLA following tangential flow fdtration (TFF) to about 8% (by absorbance at 280 nm) retained plasma protein.

[00045] Figure 13B shows an exemplary FITC-H histogram of FLOWPRA™ beads pooled Donor PPP gated on Class II HLA following tangential flow fdtration (TFF) to about 8% (by absorbance at 280 nm) retained plasma protein.

[00046] Figure 14A shows an exemplary FITC-H histogram of FLOWPRA™ beads pooled Donor PPP gated on Class I HLA following tangential flow fdtration (TFF) to about 6% (by absorbance at 280 nm) retained plasma protein.

[00047] Figure 14B shows an exemplary FITC-H histogram of FLOWPRA™ beads pooled Donor PPP gated on Class II HLA following tangential flow fdtration (TFF) to about 6% (by absorbance at 280 nm) retained plasma protein.

[00048] Figure 15A shows an exemplary FITC-H histogram of FLOWPRA™ beads pooled Donor PPP gated on Class I HLA following tangential flow fdtration (TFF) to about 1% (by absorbance at 280 nm) retained plasma protein.

[00049] Figure 15B shows an exemplary FITC-H histogram of FLOWPRA™ beads pooled Donor PPP gated on Class II HLA following tangential flow fdtration (TFF) to about 1% (by absorbance at 280 nm) retained plasma protein.

[00050] Figure 16 shows exemplary flow cytometry data of thrombosomes unstained (dark data points) or stained (light data points) with an anti-CD-41 antibody.

[00051] Figure 17 shows an exemplary histogram of thrombosomes incubated with annexin V with (light data points) and without (dark data points) calcium. [00052] Figure 18 shows an exemplary histogram of thrombosomes incubated with an anti-CD62 antibody (light data points) or with an isotype control (dark data points).

[00053] Figure 19 shows a plot of thrombin peak height for thrombosomes in the presence of PRP Reagent containing tissue factor and phospholipids (solid line and long dashes) and control cephalin (dots).

[00054] Figure 20 is an exemplary histogram comparison of low-plasma thrombosomes unstained (black) or stained with an isotype control antibody (dark gray) or a FITC-labeled 9F9 antibody (light gray), and a table showing the mean fluorescence intensity for two replicates.

[00055] Figure 21 is an exemplary histogram comparison of low-plasma thrombosomes unstained (black) or stained with an anti -P AC- 1 antibody (light gray), and a table showing the mean fluorescence intensity for two replicates.

[00056] Figure 22A is a plot of the mean fluorescence intensity of thrombosomes (1 x 10⁶ cells) treated with various concentrations of a labeled anti-CD47 antibody or an isotype control.

[00057] Figure 22B is an exemplary histogram of thrombosomes that were unstained (black), stained with an isotype control antibody (dark gray), or stained with an anti-CD47 antibody (light gray).

[00058] Figure 22C is a plot of the mean fluorescence intensity of thrombosomes (250,000 cells) treated with various concentrations of a labeled anti-CD47 antibody or an isotype control.

[00059] Figure 22D is an exemplary histogram of thrombosomes that were unstained (black), stained with an isotype control antibody (dark gray), or stained with an anti-CD47 antibody (light gray).

[00060] Figure 23A is a plot of the percent occupancy of particles of different radii in human in-date stored platelets (Batch J) and platelet derivatives (pre-lyophilization) derived therefrom as determined by dynamic light scattering (DLS).

[00061 ] Figure 23B is a plot of the percent occupancy of particles of different radii in human in-date stored platelets (Batch K) and platelet derivatives (pre-lyophilization) derived therefrom as determined by DLS. [00062] Figure 23C is a plot of the percent occupancy of particles of different radii in human in-date stored platelets (Batch L) and platelet derivatives (pre -lyophilization) derived therefrom as determined by DLS.

[00063] Figure 24A is a plot of the percent occupancy of particles of different radii in human in-date stored platelets (Batch D) and platelet derivatives (pre -lyophilization) derived therefrom as determined by DLS.

[00064] Figure 24B is a plot of the percent occupancy of particles of different radii in human in-date stored platelets (Batch E) and platelet derivatives (pre -lyophilization) derived therefrom as determined by DLS.

[00065] Figure 24C is a plot of the percent occupancy of particles of different radii in human in-date stored platelets (Batch F) and platelet derivatives (pre-lyophilization) derived therefrom as determined by DLS.

[00066] Figure 25 A is an exemplary schematic of a pathogen reduction system.

[00067] Figure 25B is a plot of the weight of a reaction vessel over time.

[00068] Figure 25C is a plot of pressure in a reaction vessel over time.

[00069] Figure 26A is a plot of the percent occupancy of particles of different radii in rehydrated thrombosomes that were (Batch N) or were not (Batch M) treated to remove pathogens, as determined by DLS.

[00070] Figure 26B is a plot of the percent occupancy of particles of different radii in rehydrated thrombosomes that were (Batch K) or were not (Batch J) treated to remove pathogens, as determined by DLS.

[00071 ] Figure 27A is a plot of the percent occupancy of particles of different radii in hIDSPs that were (Batch N) or were not (Batch M) treated to remove pathogens, as determined by DLS.

[00072] Figure 27B is a plot of the percent occupancy of particles of different radii in hIDSPs and thrombosomes derived therefrom (Batch M) that were not treated to remove pathogens, as determined by DLS. [00073] Figure 27C is a plot of the percent occupancy of particles of different radii in hIDSPs and thrombosomes derived therefrom (Batch N) that were treated to remove pathogens, as determined by DLS.

[00074] Figure 28A is a plot of the percent occupancy of particles of different radii in hIDSPs that were (Batch K) or were not (Batch J) treated to remove pathogens, as determined by DLS.

[00075] Figure 28B is a plot of the percent occupancy of particles of different radii in hIDSPs and thrombosomes derived therefrom (Batch J) that were not treated to remove pathogens, as determined by DLS.

[00076] Figure 28C is a plot of the percent occupancy of particles of different radii in hIDSPs and thrombosomes derived therefrom (Batch K) that were treated to remove pathogens, as determined by DLS.

[00077] Figure 29A is a bar plot of the transmittance of platelets, thrombosomes, and combinations thereof using light transmission aggregometry.

[00078] Figure 29B is a bar plot of the platelet (and/or thrombosome) count of platelets, thrombosomes, and combinations thereof following aggregation.

[00079] Figure 29C is a bar plot of the transmittance of platelets, thrombosomes, and combinations thereof in light transmission aggregometry.

[00080] Figure 30 is a bar plot of the transmittance of thrombin-activated platelets, thrombosomes, and combinations thereof in the presence and absence of GPRP.

[00081 ] Figure 31 is a bar plot of the percent aggregation of PMA-activated platelets, thrombosomes, and combinations thereof in the presence and absence of RGDS.

[00082] Figure 32A shows SEM of activated platelets (scale bar = 2 pm).

[00083] Figure 32B shows SEM of activated platelets (scale bar = 1 pm).

[00084] Figure 32C shows SEM of rehydrated human thrombosomes (scale bar = 2 pm).

[00085] Figure 32D shows SEM of rehydrated human thrombosomes (scale bar = 1 pm). [00086] Figure 33A is a plot of thrombosome adhesion under shear in whole blood.

[00087] Figure 33B is a plot of thrombosome adhesion under shear in plasma.

[00088] Figure 33C shows formation of fibrin in a microcapillary channel in the whole absence of GPRP.

[00089] Figure 33D shows a lack of formation of fibrin in a microcapillary channel in the presence of GPRP.

[00090] Figure 33E is a plot of the effect of GPRP on thrombosome adhesion under shear in plasma.

[00091] Figure 34A shows the aggregation response of thrombosomes in the presence of agonists, but in the absence of fresh platelets.

[00092] Figure 34B shows the aggregation response of platelet-rich plasma (PRP) in the presence of agonists, but in the absence of fresh platelets.

[00093] Figure 34C shows the comparison of aggregation of thrombosomes and PRP in the presence of 20 pM ADP.

[00094] Figure 34D shows the comparison of aggregation of thrombosomes and PRP in the presence of 10 pg/ml collagen.

[00095] Figure 34E shows the comparison of aggregation of thrombosomes and PRP in the presence of 300 pM epinephrine.

[00096] Figure 34F shows the comparison of aggregation of thrombosomes and PRP in the presence of 1 mg/ml ristocetin.

[00097] Figure 34G shows the comparison of aggregation of thrombosomes and PRP in the presence of 10 pM TRAP-6.

[00098] Figure 34H shows the comparison of aggregation of thrombosomes and PRP in the presence of 5 mg/ml arachidonic acid.

[00099] Figure 35A shows that TRAP-6 peptide is capable of promoting platelet activation by observing expression of CD62P on the apheresis platelets. [000100] Figure 35B shows that TRAP-6 peptide is not able to increase the expression of CD62P on thrombosomes.

[000101] Figure 36 shows the measurement of thrombospondin (TSP-1) by flow cytometry in terms of mean fluorescent intensity (MFI) in resting fresh platelets, activated fresh platelets, and different lots of thrombosomes.

[000102] Figure 37 shows the measurement of von Willebrand factor (vWF) by flow cytometry in terms of mean fluorescent intensity (MFI) in resting fresh platelets, activated fresh platelets, and different lots of thrombosomes.

[000103] Figure 38A shows the measurement of vWF by flow cytometry in terms of mean fluorescent intensity (MFI) in fixed lyophilized platelets, and thrombosomes.

[000104] Figure 38B shows the measurement of TSP by flow cytometry in terms of mean fluorescent intensity (MFI) in fixed lyophilized platelets, and thrombosomes.

[000105] Figure 38C shows the measurement of fibrinogen by flow cytometry in terms of mean fluorescent intensity (MFI) in fixed lyophilized platelets, and thrombosomes.

[000106] Figure 39 shows the forward scatter (FSC) measured by flow cytometry of apheresis platelets, and thrombosomes.

[000107] Figure 40 is a bar plot depicting the tail snip model results for the number of animals (mice) treated with clopidogrel and ASA (aspirin) that stopped bleeding vs those that continued to bleed in the presence of FDPDs varying in the number of cells/kg. The plot shows FDPDs enhanced return to hemostasis in DAPT-treated NOD-SCID mice.

[000108] Figure 41 shows a graph of percent platelet aggregation with time using Dual Antiplatelet Therapy (DAPT) platelets in the presence of an agonist (AA, ADP). The DAPT platelets are obtained from patients treated with prasugrel and aspirin.

[000109] Figure 42 is a bar plot of % CD41+/CD62P+ Expression (In-vitro) by DAPT donor platelets vs variable count of FDPDs. Donor blood is treated, ex-vivo, with ticagrelor and aspirin. [000110] Figure 43 is a bar plot of % CD41+/CD62P+ Expression (Ex-vivo) by DAPT donor platelets vs variable count of FDPDs. The DAPT platelets are obtained from patients treated with prasugrel and aspirin.

[000111] Figure 44 is a bar plot of PF4 expression (In-vitro) by DAPT donor platelets vs variable count of FDPDs. Donor blood is treated, ex-vivo, with ticagrelor and aspirin.

[000112] Figure 45 is a bar plot of PF4 expression (Ex-vivo) by DAPT donor platelets vs variable count of FDPDs. The DAPT platelets are obtained from patients treated with prasugrel and aspirin.

[000113] Figure 46A is a Thrombin Generation Assay (TGA) bar plot of time to peak thrombin production by DAPT donor (in-vitro) platelets vs variable count of FDPDs. Donor blood is treated, in- vitro, with ticagrelor and aspirin.

[000114] Figure 46B is a Thrombin Generation Assay (TGA) bar plot of velocity index of thrombin production by DAPT donor (in-vitro) platelets vs variable count of FDPDs. Donor blood is treated, in- vitro, with ticagrelor and aspirin.

[000115] Figure 47A is a Thrombin Generation Assay (TGA) bar plot of time to peak thrombin production by DAPT donor (ex-vivo) platelets vs variable count of FDPDs. The DAPT platelets are obtained from patients treated with prasugrel and aspirin.

[000116] Figure 47B is a Thrombin Generation Assay (TGA) bar plot of the velocity index of thrombin production by DAPT donor (ex-vivo) platelets vs variable count of FDPDs. The DAPT platelets are obtained from patients treated with prasugrel and aspirin.

[000117] As used herein and in the appended claims, the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a platelet" includes a plurality of such platelets. Furthermore, the use of terms that can be described using equivalent terms include the use of those equivalent terms. Thus, for example, the use of the term "subject" is to be understood to include the terms "patient", "individual" and other terms used in the art to indicate one who is subject to a treatment.

[000118] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the term belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present disclosure, the preferred methods and materials are now described. All publications mentioned herein are incorporated herein by reference to disclose and describe the methods and/or materials in connection with which the publications are cited. The present disclosure is controlling to the extent it conflicts with any incorporated publication. Any Headings herein are for convenience only and are not intended to be limiting, and it will be understood that the disclosure including aspects and embodiments provided within one section herein can be combined with the disclosure includes aspects and embodiments provided within any other section herein.

DETAILED DESCRIPTION

[000119] It is to be understood that the terminology used herein is for the purpose of describing particular aspects and embodiments only, and is not intended to be limiting. Further, where a range of values is disclosed, the skilled artisan will understand that all other specific values within the disclosed range are inherently disclosed by these values and the ranges they represent without the need to disclose each specific value or range herein. For example, a disclosed range of 1-10 includes 1-9, 1-5, 2-10, 3.1-6, 1, 2, 3, 4, 5, and so forth. In addition, each disclosed range includes up to 5% lower for the lower value of the range and up to 5% higher for the higher value of the range. For example, a disclosed range of 4 - 10 includes 3.8 - 10.5. This concept is captured in this document by the term "about".

[000120] “Platelets” may include, for example, platelets in whole blood, platelets in plasma, platelets in buffer optionally supplemented with select plasma proteins, cold stored platelets. Platelets may be from a mammal(s), such as of humans, or such as non-human mammals.

[000121] As used herein, “thrombosomes” (sometimes also called Tsomes) or “thrombosomes platelet derivatives” are platelet derivatives that have been treated with a preparation agent (e.g., any of the preparation agents described herein) and lyopreserved (such as freeze-dried). In some cases, thrombosomes platelet derivatives can be prepared from pooled platelets. Thrombosomes platelet derivatives can have a shelflife of 2-3 years in dry form at ambient temperature and can be rehydrated with sterile water within minutes for immediate infusion. One example of thrombosomes freeze-dried platelet derivatives are THROMBOSOMES® freeze-dried platelet derivatives (Cellphire Inc., Rockville, MD), which are in clinical trials. In non-limiting illustrative embodiments, thrombosome compositions, or illustrative freeze-dried platelet-derivative compositions herein, such as those prepared according to Example 1 herein, are compositions that include platelet derivatives, wherein at least 50% of the platelet derivatives are CD 41-positive platelet derivatives, wherein less than 15%, 10%, or in further, nonlimiting illustrative embodiments less than 5% of the CD 41-positive platelet derivatives are microparticles having a diameter of less than 0.5 pm, and wherein the platelet derivatives have a potency of at least 0.5, 1.0 and in further, non-limiting illustrative embodiments 1.5 thrombin generation potency units (TGPU) per 10⁶ platelet derivatives. In certain illustrative embodiments, including non-limiting examples of the illustrative embodiment in the preceding sentence, the platelet derivatives are at least 0.5 pm in diameter, and in some embodiments 0.5 to 2.5 pm in diameter.

Reduced plasma protein content and antibodies

[000122] Transfusion-related acute lung injury (TRALI) is a condition believed to be caused by the presence of antibodies (e.g., Human Leukocyte Antigen (HLA), Human Neutrophil Antigen (HNA), or granulocyte antibodies) in a transfused blood product, which can react with antigens in a transfusion recipient.

[000123] The use of plasma-based blood products from donors considered to be high-risk or who test positive for Human Leukocyte Antigen (HLA) Class I, Class II, and neutrophil-specific antibodies are banned from use in transfusion or production of human-derived platelet products (e.g., compositions comprising platelets and/or platelet derivatives (e.g., thrombosomes)) and are therefore omitted from the donor pool.

[000124] The use of tangential flow filtration (TFF) or multi-pass centrifugation can reduce the amount of antibody in a blood product, for example, to limits not detectable by current, FDA-approved, testing methods. In some cases, reduction of certain plasma components (e.g., HLA antibodies) can allow for this donor population to be accepted for production of blood products (e.g., compositions comprising platelets and/or platelet derivatives (e.g., thrombosomes)). In some embodiments described herein, a blood product can be a composition that includes platelets and an aqueous medium.

[000125] Thrombosomes or cryopreserved platelet production can be limited by the availability of licensed apheresis collections performed at blood donor centers around the United States. Competition for these products can be fierce, and distribution for blood product manufacturing needs is usually prioritized below the needs of patient care. Blood product manufacturing (e.g., scale-up), could be aided by apheresis collections from otherwise deferred donors. One way this could be accomplished is by reducing free antibody levels in donor plasma to meet current, FDA approved, testing thresholds by utilizing tangential flow filtration (TFF) or centrifugation and plasma removal. Centrifugation of the raw materials (e.g., donor plasma), while typically more time consuming than TFF, can have a similar effect on the raw material. In some cases, removal of the donor plasma and replacement with buffer can allow the inventors to manufacture and characterize a final product (e.g., compositions comprising platelets and/or platelet derivatives (e.g., thrombosomes)) with a reduced protein (e.g., antibody (e.g., HLA antibody or HNA antibody)) content (e.g., as measured by absorbance at 280 nm). Such a product can increase the safety for a recipient of the product by reducing the transfusion related cause for TRALI.

[000126] In some embodiments, the materials and methods provided herein can allow previously deferred donors (such as those who screen positive for HLA antibodies or whose donor history presents a risk for positive HLA) to be allowed into the donor pool of raw materials used to manufacture blood products (e.g., compositions comprising platelets and/or platelet derivatives (e.g., thrombosomes)). In some embodiments described herein, a blood product can be a composition that includes platelets and an aqueous medium. Additionally, a reduction in HLA antibodies from the raw materials (e.g., donor apheresis material (e.g., platelets or pooled platelets)) can allow for a final product (e.g., compositions comprising platelets and/or platelet derivatives (e.g., thrombosomes)) to be labeled as HLA-reduced, increasing the safety of a product for a recipient.

[000127] In some embodiments, a blood product (e.g., compositions comprising platelets and/or platelet derivatives (e.g., thrombosomes)) as provided herein can have no detectable level of HLA antibodies. In some embodiments, a blood product (e.g., compositions comprising platelets and/or platelet derivatives (e.g., thrombosomes)) as provided herein can have no detectable level of an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies. In some embodiments, a blood product (e.g., compositions comprising platelets and/or platelet derivatives (e.g., thrombosomes)) as provided herein can have no detectable level of HLA Class I antibodies. In some embodiments, a blood product (e.g., compositions comprising platelets and/or platelet derivatives (e.g., thrombosomes)) as provided herein can have no detectable level of HLA Class II antibodies. In some embodiments, a blood product (e.g., compositions comprising platelets and/or platelet derivatives (e.g., thrombosomes)) as provided herein can have no detectable level of HNA antibodies. In some embodiments, detection of antibodies can be carried out using a regulatory agency approved (e.g., FDA cleared) assay. A regulatory agency approved assay can be any appropriate regulatory agency approved assay. In some embodiments, a regulatory agency approved test can be the LABSCREEN™ Mixed by One Lambda. In some implementations, a regulatory agency approved test can be carried out using a LUMINEX® 100/200 or a LUMINEX® XY and the HLA FUSION™ software. In some embodiments described herein, a blood product can be a composition that includes platelets and an aqueous medium.

[000128] In some embodiments, a blood product (e.g., compositions comprising platelets and/or platelet derivatives (e.g., thrombosomes)) as provided herein can have a level of an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies below a reference level. In some embodiments, a blood product (e.g., compositions comprising platelets and/or platelet derivatives (e.g., thrombosomes)) as provided herein can have a level of HLA Class I antibodies below a reference level. In some embodiments, a blood product (e.g., compositions comprising platelets and/or platelet derivatives (e.g., thrombosomes)) as provided herein can have a level of HLA Class II antibodies below a reference level. In some embodiments, a blood product (e.g., a composition comprising platelets and/or platelet derivatives (e.g., thrombosomes)) as provided herein can have a level of HNA antibodies below a reference level. A reference level can be any appropriate reference level. In some embodiments described herein, a blood product can be a composition that includes platelets and an aqueous medium.

[000129]In some embodiments, a blood product (e.g., a composition comprising platelets and/or platelet derivatives (e.g., thrombosomes)) as provided herein test negative for an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies in a regulatory agency approved assay (e.g., an FDA cleared assay). In some embodiments, a blood product (e.g., a composition comprising platelets and/or platelet derivatives (e.g., thrombosomes)) as provided herein can test negative for HLA Class I antibodies in a regulatory agency approved assay (e.g., an FDA cleared assay). In some embodiments, a blood product (e.g., a composition comprising platelets and/or platelet derivatives (e.g., thrombosomes)) as provided herein can test negative for HLA Class II antibodies a in regulatory agency approved assay (e.g., an FDA cleared assay). In some embodiments, a blood product (e.g., a composition comprising platelets and/or platelet derivatives (e.g., thrombosomes)) as provided herein can test negative for HNA antibodies in a regulatory agency approved assay (e.g., an FDA cleared assay). In some embodiments described herein, a blood product can be a composition that includes platelets and an aqueous medium. A regulatory agency approved assay can be any appropriate regulatory agency approved assay. In some embodiments, a regulatory agency approved test can be the LABSCREEN™ Mixed by One Lambda. In some implementations, a regulatory agency approved test can be carried out using a LUMINEX® 100/200 or a LUMINEX® XY and the HLA FUSION™ software.

[000130] In some aspects, provided herein are compositions comprising platelets and/or platelet derivatives (e.g., thrombosomes) and an aqueous medium. In some embodiments, the aqueous medium can include a preparation agent (e.g., any of the preparation agents described herein). In some embodiments, an aqueous medium as provided herein can have a level of an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies below a reference level. In some embodiments, an aqueous medium as provided herein can have a level of HLA Class I antibodies below a reference level. In some embodiments, an aqueous medium as provided herein can have a level of HLA Class II antibodies below a reference level. In some embodiments, an aqueous medium as provided herein can have a level of HNA antibodies below a reference level. A reference level can be any appropriate reference level. In some embodiments, an aqueous medium as provided herein can test negative for an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies in a regulatory agency approved assay (e.g., an FDA cleared assay). In some embodiments, an aqueous medium as provided herein can test negative for HLA Class I antibodies in a regulatory agency approved assay (e.g., an FDA cleared assay). In some embodiments, an aqueous medium as provided herein can test negative for HLA Class II antibodies in a regulatory agency approved assay (e.g., an FDA cleared assay). In some embodiments, an aqueous medium as provided herein can test negative for HNA antibodies in a regulatory agency approved assay (e.g., an FDA cleared assay). A regulatory agency approved assay can be any appropriate regulatory agency approved assay. In some embodiments, a regulatory agency approved test can be the LABSCREEN™ Mixed by One Lambda. In some implementations, a regulatory agency approved test can be carried out using a LUMINEX® 100/200 or a LUMINEX® XY and the HLA FUSION™ software.

[000131] In some embodiments, an aqueous medium can have a reduced amount of residual plasma compared to donor apheresis plasma (e.g., single-donor apheresis plasma or pooled donor apheresis plasma) can be a percentage of residual plasma (e.g., less than or equal to about 50%, 40%, 30%, 20%,

15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, or 0. 1% of residual plasma). In some embodiments, an aqueous medium can have a reduced amount of residual plasma compared to donor apheresis plasma (e.g., single-donor apheresis plasma or pooled donor apheresis plasma) can be a percentage range of residual plasma (e.g., about 5% to about 50%, about 5% to about 40%, about 5% to about 30%, about 5% to about 20%, about 5% to about 15%, about 5% to about

10%, about 10% to about 20%, about 7% to about 15%, about 7% to about 10%, about 8% to about 15%, about 8% to about 10%, about 0. 1% to about 5%, about 0. 1% to about 3%, about 0.1% to about 1%, about

0.5% to about 3%, about 0.5% to about 1%, or about 1% to about 3% of residual plasma). In some embodiments, an aqueous medium can have a protein concentration less than or equal to about 50% (e.g., less than or equal to about 40%, 30%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.9%,

0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, or 0.1%) of the protein concentration of donor apheresis plasma (e.g., single-donor apheresis plasma or pooled donor apheresis plasma). In some embodiments, an aqueous medium can have a protein concentration of about 5% to about 50% (e.g., about 5% to about

40%, about 5% to about 30%, about 5% to about 20%, about 5% to about 15%, about 5% to about 10%, about 10% to about 20%, about 7% to about 15%, about 7% to about 10%, about 8% to about 15%, or about 8% to about 10%) of the protein concentration of donor apheresis plasma (e.g., single-donor apheresis plasma or pooled donor apheresis plasma). In some embodiments, an aqueous medium can have a protein concentration of about 0. 1% to about 5% (e.g., about 0. 1% to about 3%, about 0. 1% to about 1%, about 0.5% to about 3%, about 0.5% to about 1%, about 1% to about 2%, or about 1% to about 3%) of the protein concentration of donor apheresis plasma (e.g., single-donor apheresis plasma or pooled donor apheresis plasma). A protein concentration can be measured by any appropriate method. Apart from the relative protein concentration of proteins in the aqueous medium, the protein concentration in the aqueous medium can also be measured in absolute terms. Accordingly, in some embodiments, a protein concentration can be measured by absorbance at 280 nm (A280). In some embodiments, an aqueous medium can have an A280 that is less that is less than 2.0 AU (e.g., less than 1.97, 1.95, 1.93, 1.90, 1.87, 1.85, 1.83, 1.80, 1.77, 1.75, 1.73, 1.70, 1.66, 1.6, 1.5, 1.4, 1.3, 1.2, 1.1, 1.0, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, or 0. 1 AU) with a path length of 0.5 cm. In some embodiments, the protein concentration in the aqueous medium is less than or equal to 15%, 14%, 13%, 12%, 11%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.1%, or 0.01%. In some illustrative embodiments, the protein concentration is less than 3% or 4%. In some embodiments, the protein concentration is in the range of 0.01-15%, 0. 1-15%, 1-15%, 1- 10%, 0.1-10%, 0.01-10%, 0.1-5%, 0.1-4%, 0.1-3%, 0.1-2%, 0.1-1%, 1-5%, 1-4%, 1-3%, 1-2%, 3-12%, or 5-10%. In some embodiments, an aqueous medium can have a HLA Class I antibody concentration less than about 70% (e.g., less than about 60%, 50%, 40%, 30%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, or 0.1%) of the HLA Class I antibody concentration of donor apheresis plasma (e.g., single-donor apheresis plasma or pooled donor apheresis plasma). A HLA Class I antibody concentration can be measured by any appropriate method. In some embodiments, the HLA class I antibody concentration in the aqueous medium can be quantitated in absolute terms such that the aqueous medium can have HLA Class I antibody concentration less than about 70% (e.g., less than about or less than exactly 60%, 50%, 40%, 30%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, or 0.1%) in the aqueous medium. In some embodiments, the HLA Class I antibody in the aqueous medium is low enough such that the composition comprising platelet derivatives and aqueous medium is negative for HLA Class I antibodies based on a regulatory agency approved test for HLA Class I antibodies.

[000132] In some embodiments, an aqueous medium can have a HLA Class II antibody concentration less than about 50% (e.g., less than about 40%, 30%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, or 0.1%) of the HLA Class II antibody concentration of donor apheresis plasma (e.g., single-donor apheresis plasma or pooled donor apheresis plasma). A HLA Class II antibody concentration can be measured by any appropriate method. In some embodiments, the HLA class II antibody concentration in the aqueous medium can be quantitated in absolute terms such that the aqueous medium can have HLA Class I antibody concentration less than about 50% (e.g., less than about or less than exactly 40%, 30%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, or 0.1%) in the aqueous medium. In some embodiments, the HLA Class II antibody in the aqueous medium is low enough such that the composition comprising platelet derivatives and aqueous medium is negative for HLA Class II antibodies based on a regulatory agency approved test for HLA Class II antibodies.

[000133] In some embodiments, an aqueous medium can have a HNA antibody concentration less than about 50% (e.g., less than about 40%, 30%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, or 0. 1%) of the HNA antibody concentration of donor apheresis plasma (e.g., single-donor apheresis plasma or pooled donor apheresis plasma). A HNA antibody concentration can be measured by any appropriate method. In some embodiments, the HNA antibody concentration in the aqueous medium can be quantitated in absolute terms such that the aqueous medium can have HNA antibody concentration less than about 50% (e.g., less than about or less than exactly 40%, 30%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, or 0.1%) in the aqueous medium. In some embodiments, the HNA antibody in the aqueous medium is low enough such that the composition comprising platelet derivatives and aqueous medium is negative for HNA antibodies based on a regulatory agency approved test for HNA antibodies.

[000134] In some cases, flow cytometry can be used to evaluate compositions as provided herein. In some embodiments, an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies, as determined for a composition comprising platelets and an aqueous medium by flow cytometry using beads coated with Class I HLAs, Class II HLAs, or HNAs, respectively, is less than 10% (e.g., less than about or less than exactly 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, or 0.1%). In some embodiments, the percentage of beads positive for HLA Class I antibodies, as determined for a composition comprising platelets and an aqueous medium by flow cytometry using beads coated with Class I HLAs, is less than 10% (e.g., less than 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, or 0. 1%). In some embodiments, the percentage of beads positive for HLA Class II antibodies, as determined for a composition comprising platelets and an aqueous medium by flow cytometry using beads coated with Class II HLAs is less than 10% (e.g., less than about or less than exactly 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, or 0.1%). In some embodiments, the percentage of beads positive for HNA antibodies, as determined for a composition comprising platelets and an aqueous medium by flow cytometry using beads coated with HNAs is less than 10% (e.g., less than about or less than exactly 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, or 0.1%). [000135] In some embodiments, an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies, as determined for an aqueous medium by flow cytometry using beads coated with Class I HLAs, Class II HLAs, or HNAs, respectively, is less than 10% (e.g., less than 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, or 0. 1%). In some embodiments, the percentage of beads positive for HLA Class I antibodies, as determined for an aqueous medium by flow cytometry using beads coated with Class I HLAs, is less than 10% (e.g., less than 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, or 0. 1%). In some embodiments, the percentage of beads positive for HLA Class II antibodies, as determined for an aqueous medium by flow cytometry using beads coated with Class II HLAs is less than 10% (e.g., less than 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, or 0. 1%). In some embodiments, the percentage of beads positive for HNA antibodies, as determined for an aqueous medium by flow cytometry using beads coated with HNAs is less than 10% (e.g., less than 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, or 0.1%).

[000136] In some embodiments, the protein concentration is low enough to exclude the HLA Class I, HLA Class II, and HNA antibodies from the donor pheresis plasma such that the composition is negative for: a) HLA Class I antibodies based on a regulatory agency approved test for HLA Class I antibodies; b) HLA Class II antibodies based on a regulatory agency approved test for HLA Class II antibodies; and c) HNA antibodies based on a regulatory agency approved test for HNA antibodies. The platelet derivative composition of the present disclosure, and the process for obtaining the same, thus provides the flexibility to utilize the apheresis plasma from different multiple donors, and yet obtain a final product (platelet derivative composition) that is negative for the HLA Class I, HLA Class II, and HNA antibodies.

[000137] In some aspects, provided herein are platelet derivative compositions comprising platelet derivatives in the form of a solid, a composition with less than 1% water, and/or a powder. The composition in solid form, in illustrative embodiments dried form, for example with less than 1% water, can be one amongst different kinds in which the composition would be packed and commercialized. Thus, it is contemplated that the composition in the dried form would preserve the characteristics with respect to the low content, or even absence of detectable HLA Class I, HLA Class II, and HNA antibodies as described with respect to the aqueous medium in the embodiments described herein. In some embodiments, the platelet derivative composition in the form of a powder is negative for HLA Class I antibodies based on a regulatory agency approved test for HLA Class I antibodies. In some embodiments, the platelet derivative composition in the form of a powder is negative for HLA Class II antibodies based on a regulatory agency approved test for HLA Class II antibodies. In some embodiments, the platelet derivative composition in the form of a powder is negative for HNA antibodies based on a regulatory agency approved test for HNA antibodies. In some embodiments, the platelet derivative composition in the form of a powder is negative for HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies based on a regulatory agency approved test for HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies, respectively.

Quantity of platelet or platelet derivatives, and erythrocytes

[000138] The composition comprising platelet derivatives and aqueous medium can have varying quantity of platelets and/or platelet derivatives along with erythrocytes. In some embodiments, a composition as described herein can have a platelet count of at least 10⁶ (e.g., at least 5 x 10⁶, 10⁷, 5 x 10⁷, 10⁸, 5 x 10⁸, 10⁹, 5 x 10⁹, or 10¹⁰). In some embodiments, a composition as described herein can have a platelet count of at least about 200 x 10³ platelets/pL (e.g., at least about 300 x 10³, 400 x 10³, 500 x 10³, 750 x 10³, 1000 x 10³, 1500 x 10³, 2000 x 10³, or 2500 x 10³ platelets/pL). In some embodiments, a composition as described herein can have a platelet count of at least about 2000 x 10³ platelets/pL (e.g., at least about 2050 x 10³, 2100 x 10³, 2150 x 10³, 2200 x 10³, 2250 x 10³, 2300 x 10³, 2350 x 10³, 2400 x 10³, 2450 x 10³, or 2500 x 10³ plate lets/pL). In some embodiments, a composition as described herein can have a platelet count less than or equal to 1000 x I ⁴ platelets/pL. In some embodiments, the platelets or platelet derivatives in the composition are at least 100 x 10³ platelets/pL, or 200 x 10³ platelets/pL, or 400 x 10³ platelets/pL, or 1000 x 10³ plate Icts/pL. or 1250 x 10³ platelets/pL, or 1500 x 10³ platelets/pL, or 1750 x 10³ platelets/pL, 2000 x 10³ platelets/pL, or 2250 x 10³ platelets/pL, or 2500 x 10³ platelets/pL, or 2750 x 10³ platelets/pL, or 3000 x 10³ platelets/pL, 3250 x 10³ platelets/pL, 3500 x 10³ platelets/pL, 3750 x 10³ platelets/pL, 4000 x 10³ platelets/pL, or 4250 x 10³ platelets/pL, or 4500 x 10³ platelets/pL, or 4750 x 10³ platelets/pL, or 5000 x 10³ platelets/pL, or 5250 x 10³ platelets/pL, or 5500 x 10³ platelets/pL, or 5750 x 10³ platelets/pL, or 6000 x 10³ platelets/pL, or 7000 x 10³ platelets/pL, or 8000 x 10³ platelets/pL, or 9000 x 10³ platelets/pL, or 10,000 x 10³ platelets/pL, or 11,000 x 10³ platelets/pL, or 12,000 x 10³ platelets/pL, or 13,000 x 10³ platelets/pL, or 14,000 x 10³ platelets/pL, or 15,000 x 10³ platelets/pL, or 16,000 x 10³ platelets/pL, or 17,000 x 10³ platelets/pL, or 18,000 x 10³ platelets/pL, or 19,000 x 10³ platelets/pL, or 20,000 x 10³ platelets/pL. In some embodiments, the platelets or platelet derivatives in the composition is in the range of 100 x 10³ - 20,000 x 10³ platelets/pL, or 1000 x 10³ - 20,000 x 10³ platelets/pL, or 1000 x 10³ - 10,000 x 10³ platelets/pL, or 500 x 10³ - 5,000 x 10³ platelets/pL, or 1000 x 10³ - 5,000 x 10³ platelets/pL, or 2000 x 10³ - 8,000 x 10³ platelets/pL, or 10,000 x 10³ - 20,000 x 10³ platelets/pL, or 15,000 x 10³ - 20,000 x 10³ platelets/pL. [000139] In some embodiments, a composition as provided herein can include erythrocytes. In some embodiments, a composition as provided herein can have an erythrocyte count of less than about IO¹⁰ (e.g., less than 5 x IO⁹, 10⁹, 5 x 10⁸, 10⁸, 5 x 10⁷, 10⁷, 5 x 10⁶, or 10⁶). In some embodiments, the erythrocyte count can be less than 0.2 x 10⁶/pL (e.g., less than 0.1 x 10⁶/pL, 0.5 x 10⁵/pL, or 0.1 x 10⁵/pL). In some embodiments, the erythrocytes in the composition is in the range of 0. 1 x 10⁵ erythrocytes/ pL to 0.2 x 10⁶ erythrocytes/pL, or 0.5x 10⁵ erythrocytes/ pL to 0. 1 x 10⁶ erythrocytes/pL.

Preparation agent and additional components

[000140] In some embodiments, a composition provided herein can include one or more additional components. In some embodiments, a composition provided herein can include a preparation agent (e.g., any of the preparation agents described herein). In some embodiments, the composition can include a buffering agent, a base, a loading agent, optionally a salt, and optionally at least one organic solvent. A buffering agent can be any appropriate buffering agent. In some embodiments, a buffering agent can be HEPES (4-(2 -hydroxyethyl)- 1 -piperazineethanesulfonic acid). A base can be any appropriate base. In some embodiments, a base can be sodium bicarbonate. A loading agent can be any appropriate loading agent. In some embodiments, a loading agent can be a monosaccharide, a polysaccharide, or a combination thereof. In some embodiments, a loading agent can be selected from the group consisting of sucrose, maltose, trehalose, glucose, mannose, and xylose. In some embodiments, a loading agent can be trehalose. In some embodiments, a polysaccharide can be polysucrose. A salt can be any appropriate salt. In some embodiments, a salt can be sodium chloride, potassium chloride, or a combination thereof. An organic solvent can be any appropriate organic solvent. In some embodiments, an organic solvent can be selected from the group consisting of ethanol, acetic acid, acetone, acetonitrile, dimethylformamide, dimethyl sulfoxide, dioxane, methanol, n-propanol, isopropanol, tetrahydrofuran (THF), N-methyl pyrrolidone, dimethylacetamide (DMAC), and combinations thereof.

[000141] A preparation agent can include any appropriate components. In some embodiments, the preparation agent may comprise a liquid medium. In some embodiments the preparation agent may comprise one or more salts selected from phosphate salts, sodium salts, potassium salts, calcium salts, magnesium salts, and any other salt that can be found in blood or blood products, or that is known to be useful in drying platelets, or any combination of two or more of these.

[000142] In some embodiments, the preparation agent comprises one or more salts, such as phosphate salts, sodium salts, potassium salts, calcium salts, magnesium salts, and any other salt that can be found in blood or blood products. Exemplary salts include sodium chloride (NaCl), potassium chloride (KC1), and combinations thereof. In some embodiments, the preparation agent includes from about 0.5 mM to about 100 mM of the one or more salts. In some embodiments, the preparation agent includes from about 0.5 mM to about 100 mM (e.g., about 0.5 to about 2 mM, about 2 mM to about 90 mM, about 2 mM to about 6 mM, about 50 mM to about 100 mM, about 60 mM to about 90 mM, about 70 to about 85 mM) of the one or more salts. In some embodiments, the preparation agent includes about 5 mM, about 75 mM, or about 80 mM of the one or more salts. In some embodiments, the preparation agent comprises one or more salts selected from calcium salts, magnesium salts, and a combination of the two, in a concentration of about 0.5 mM to about 2 mM.

[000143] Preferably, these salts are present in the composition comprising platelets or platelet derivatives, such as freeze-dried platelets, at an amount that is about the same as is found in whole blood.

[000144] In some embodiments, the preparation agent further comprises a carrier protein. In some embodiments, the carrier protein comprises human serum albumin, bovine serum albumin, or a combination thereof. In some embodiments, the carrier protein is present in an amount of about 0.05% to about 1.0% (w/v).

[000145] The preparation agent may be any buffer that is non-toxic to the platelets and provides adequate buffering capacity to the solution at the temperatures at which the solution will be exposed during the process provided herein. Thus, the buffer may comprise any of the known biologically compatible buffers available commercially, such as phosphate buffers, such as phosphate buffered saline (PBS), bicarbonate/carbonic acid, such as sodium-bicarbonate buffer, N-2-hydroxyethylpiperazine-N'-2- ethanesulfonic acid (HEPES), and tris-based buffers, such as tris-buffered saline (TBS). Likewise, it may comprise one or more of the following buffers: propane- 1,2,3-tricarboxylic (tricarballylic); benzenepentacarboxylic; maleic; 2,2- dimethylsuccinic; EDTA; 3, 3 -dimethylglutaric; bis(2- hydroxyethyl)imino- tris(hydroxymethyl)-methane (BIS-TRIS); benzenehexacarboxylic (mellitic); N-(2- acetamido)imino-diacetic acid (ADA); butane-l,2,3,4-tetracarboxylic; pyrophosphoric; 1,1- cyclopentanediacetic (3,3 tetramethylene-glutaric acid); piperazine- l,4-bis-(2 -ethane sulfonic acid) (PIPES); N-(2 -acetamido )-2- amnoethanesulfonic acid (ACES); 1,1 -cyclohexanediacetic; 3,6- endomethylene- 1,2,3,6-tetrahydrophthalic acid (EMTA; ENDCA); imidazole; 2- (aminoethyl)trimethylammonium chloride (CHOLAMINE); N,N-bis(2- hydroxyethyl)-2- aminoethanesulfonic acid (BES); 2-methylpropane-l,2,3- triscarboxylic (beta-methyltricarballylic ); 2- (N-morpholino)propane-sulfonic acid (MOPS); phosphoric; and N-tris(hydroxymethyl)methyl-2- amminoethane sulfonic acid (TES). In some embodiments, the preparation agent includes one or more buffers, e.g., N-2-hydroxyethylpiperazine-N'-2- ethane sulfonic acid (HEPES), or sodium-bicarbonate (NaHCOs). In some embodiments, the preparation agent includes from about 5 to about 100 mM of the one or more buffers. In some embodiments, the preparation agent includes from about 5 to about 50 mM (e.g., from about 5 mM to about 40 mM, from about 8 mM to about 30 mM, about 10 mM to about 25 mM) about of the one or more buffers. In some embodiments, the preparation agent includes about 10 mM, about 20 mM, about 25 mM, or about 30 mM of the one or more buffers.

[000146] In some embodiments, the preparation agent includes one or more saccharides, such as monosaccharides and disaccharides, including sucrose, maltose, trehalose, glucose, mannose, dextrose, and xylose. In some embodiments, the saccharide is a monosaccharide. In some embodiments, the saccharide is a disaccharide. In some embodiments, the saccharide is a monosaccharide, a disaccharide, or a combination thereof. In some embodiments, the saccharide is a non-reducing disaccharide. In some embodiments, the saccharide is sucrose, maltose, trehalose, glucose (e.g., dextrose), mannose, or xylose. In some embodiments, the saccharide comprises trehalose. In some embodiments, the preparation agent comprises a starch. In some embodiments, the preparation agent includes polysucrose, a polymer of sucrose and epichlorohydrin. In some embodiments, the preparation agent includes from about 10 mM to about 1,000 mM of the one or more saccharides. In some embodiments, the preparation agent includes from about 50 to about 500 mM of the one or more saccharides. In some embodiments, one or more saccharides is present in an amount of from 10 mM to 500 mM. In some embodiments, one or more saccharides is present in an amount of from 50 mM to 200 mM. In some embodiments, one or more saccharides is present in an amount from 100 mM to 150 mM. In some embodiments, the one or more saccharides are the lyophilizing agent; for example, in some embodiments, the lyophilizing agent comprises trehalose, polysucrose, or a combination thereof. In some embodiments, the preparation agent comprises trehalose in the range of 0.4-35%, or 1-35%, or 2-30%, or 1-10%, or 1-5%, or 0.5-5%. In an exemplary embodiment, the composition comprises 3.5% trehalose. In some embodiments, the preparation agent comprises polysucrose in the range of 2-8%, or 2.25-7.75%, or 2.5-7.5%, or 2.5-6.5%, wherein the composition is in a rehydrated form. In an exemplary embodiment, the composition comprises 3% polysucrose. In another exemplary embodiment, the composition comprises 6% polysucrose. Different ionic forms of poly sucrose can be used in the preparation agent that would be used to lyophilize the platelet derivatives. The ionic forms of polysucrose can be exploited to increase the efficiency of the lyophilization process. The ionic forms can be optimized to accommodate higher concentrations of platelet concentrations in the solution for performing lyophilization process. In some embodiments of the composition, wherein the composition comprises polysucrose, the polysucrose is a cationic form of polysucrose. In some embodiments, the cationic form of polysucrose is diethylaminoethyl (DEAE)-polysucrose. In some embodiments, the polysucrose is an anionic form of polysucrose. In some

33

RECTIFIED SHEET (RULE 91 ) ISA/EP embodiments, the anionic form of polysucrose is carboxymethyl -polysucrose. Polysucrose of different molecular weight can be used to increase the efficiency of the lyophilization process. In some embodiments of the composition, poly sucrose has a molecular weight in the range of 70,000 MW to 400,000 MW. In some embodiments, polysucrose has a molecular weight in the range of 80,000 MW to 350,000 MW, or 100,000 MW to 300,00 MW. In some exemplary embodiments, polysucrose has a molecular weight in the range of 120,000 MW to 200,000 MW. In some exemplary embodiments, polysucrose has a molecular weight of 150,000 MW, or 160,000 MW, or 170,000 MW, or 180,000 MW, 190,000 MW, or 200,000 MW.

[000147] In some embodiments the composition comprising platelets or platelet derivatives,

(e.g., thrombosomes), may comprise one or more of water or a saline solution. In some embodiments the composition comprising platelets or platelet derivatives, such as freeze-dried platelets, may comprise DMSO.

[000148] In some embodiments, the preparation agent comprises an organic solvent, such as an alcohol (e.g., ethanol). In such a preparation agent, the amount of solvent can range from 0.1 % to 5.0 % (v/v). In some embodiments, the organic solvent can range from about 0.1 % (v/v) to about 5.0 % (v/v), such as from about 0.3 % (v/v) to about 3.0 % (v/v), or from about 0.5 % (v/v) to about 2 % (v/v).

[000149] In some embodiments, suitable organic solvents include, but are not limited to alcohols, esters, ketones, ethers, halogenated solvents, hydrocarbons, nitriles, glycols, alkyl nitrates, water or mixtures thereof. In some embodiments, suitable organic solvents includes, but are not limited to methanol, ethanol, n-propanol, isopropanol, acetic acid, acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl acetate, ethyl acetate, isopropyl acetate, tetrahydrofuran, isopropyl ether (IPE), tert-butyl methyl ether, dioxane (e.g., 1,4-dioxane), acetonitrile, propionitrile, methylene chloride, chloroform, toluene, anisole, cyclohexane, hexane, heptane, ethylene glycol, nitromethane, dimethylformamide, dimethyl sulfoxide, N-methyl pyrrolidone, dimethylacetamide, and combinations thereof. In some embodiments the organic solvent is selected from the group consisting of ethanol, acetic acid, acetone, acetonitrile, dimethylformamide, dimethyl sulfoxide (DMSO), dioxane, methanol, n-propanol, isopropanol, tetrahydrofuran (THF), N-methyl pyrrolidone, dimethylacetamide (DMAC), or combinations thereof. In some embodiments, the organic solvent comprises ethanol, DMSO, or a combination thereof. The presence of organic solvents, such as ethanol, can be beneficial in the processing of platelets, platelet derivatives, or thrombosomes (e.g., freeze-dried platelet derivatives). [000150] In some embodiments the preparation agent does not include an organic solvent. In some embodiments, the preparation agent comprises an organic solvent. In some embodiments the preparation agent comprises DMSO.

[000151] A preparation agent can have any appropriate pH. For example, in some embodiments, a preparation agent can have a pH of about 5.5 to about 8.0 (e.g., about 6.5 to about 6.9, or about 6.6 to about 6.8). In some embodiments, the preparation agent has a pH in the range of 5.5 to 8.0, or 6.0 to 8.0, or 6.0 to 7.5. In an exemplary embodiment, the preparation agent has a pH of 6.5. In another exemplary embodiment, the preparation agent has a pH of 7.4.

[000152] In some embodiments, one or more other components may be combined with in the platelets (e.g., as part of a preparation agent). Exemplary components may include Prostaglandin El or Prostacyclin and or EDTA/EGTA to prevent platelet aggregation and activation.

[000153] In some embodiments, a preparation agent can be Buffer A, as shown in Example

1. In some embodiments, a preparation agent can comprise Buffer A, as shown in Example 1, wherein one or more components (e.g., ethanol) is present in an amount up to three times the amount shown in Example 1. Non-limiting examples of preparation agent compositions that may be used are shown in Tables P1-P6.

[000154] Table P5 shows the concentrations of HEPES and salts in Buffer B. The pH can be adjusted to 7.4 with NaOH. Albumin is an optional component of Buffer B.

[000155] Table P6.

[000156] Table P6 is another exemplar, preparation agent.

Rehvdration of the composition comprising platelet derivatives

[000157] In some aspects, the platelet derivative composition of the present disclosure is in the form of a powder. In some aspects, the process for preparing the platelet derivative composition results in the final product which is in a dry powdered form. The platelet derivative composition in its dry form comprises platelet derivatives. The platelet derivative composition in its dry form comprises platelet derivatives, and/or freeze-dried platelets. It is well-known to a skilled artisan that the platelet derivatives in the dried

37

RECTIFIED SHEET (RULE 91 ) ISA/EP form shall preserve the characteristics which it is intended to observe once the platelet derivatives are rehydrated for clinical application and/or studying the characteristics such as, the presence of platelet activation markers.

[000158] In some embodiments, rehydrating the composition comprising platelets or platelet derivatives comprises adding to the platelets an aqueous liquid. In some embodiments, the aqueous liquid is water. In some embodiments, the aqueous liquid is an aqueous solution (e.g., a buffer). In some embodiments, the aqueous liquid is a saline solution. In some embodiments, the aqueous liquid is a suspension.

[000159] In some embodiments, the platelets or platelet derivatives (e.g., thrombosomes) have less than about 10%, such as less than about 8%, such as less than about 6%, such as less than about 4%, such as less than about 2%, such as less than about 0.5% crosslinking of platelet membranes via proteins and/or lipids present on the membranes. In some embodiments, the rehydrated platelets or platelet derivatives (e.g., thrombosomes), have less than about 10%, such as less than about 8%, such as less than about 6%, such as less than about 4%, such as less than about 2%, such as less than about 0.5% crosslinking of platelet membranes via proteins and/or lipids present on the membranes.

[000160] In some embodiments, rehydrating the composition comprising platelets or platelet derivatives comprises adding to the platelets or platelet derivatives sterile water (e.g., sterile water for injection) over about 10 minutes at about room temperature. In general, the rehydration volume is about equal to the volume used to fdl each vial of platelet derivative composition prior to drying, for example, freeze- drying.

Process for preparing a platelet derivative composition

[000161] In some embodiments, the platelets or pooled platelets can be initially diluted, further diluted (e.g. if initially diluted in an acidified buffer) or suspended in a preparation agent as described herein before being loaded onto a TFF unit to exchange the solution, buffer or diluted preparation agent with a preparation agent in the TFF unit. A skilled artisan would understand that before being loaded onto a TFF unit, the input composition can be initially diluted to a desirable dilution in order to carry out the TFF process in an effective manner. In some embodiments, the platelets or pooled platelets comprised in a composition can be diluted with an acidified washing buffer for example, and/or with a preparation agent as described herein before loading onto a TFF unit. In some embodiments, the platelets or pooled platelets are diluted 1:0.5, 1: 1, 1:2, 1:4, 1:5, or 1: 10, in a preparation agent, which in illustrative embodiments is the preparation in which the platelets will be freeze dried. In illustrative embodiments, the platelets or the pooled platelets can be diluted or suspended in a preparation agent comprising trehalose and in illustrative embodiments polysucrose before being loaded onto a TFF unit, followed by performing TFF with the preparation agent in the TFF unit. In illustrative embodiments, the platelets or the pooled platelets can be diluted or suspended in a preparation agent comprising 0.4 to 35% trehalose and 2% to 8% polysucrose, before being loaded onto a TFF unit, followed by performing TFF with the preparation agent in the TFF unit. A skilled artisan would understand that performing TFF is a continuous process of fluid exchange between the preparation agent and the platelets or the pooled platelets. The preparation agent that is used to dilute or suspend the platelets or the pooled platelets before being loaded onto a TFF unit can be the same preparation agent that is used for performing the TFF or it can be a different solution (e.g., acidified washing buffer) typically that is compatible with processing viable platelets. In some embodiments, the preparation agent used to dilute or suspend the platelets or the pooled platelets before being loaded onto a TFF unit can have the same ingredients but differ in the concentration of the ingredients than the preparation agent used for performing the TFF. A skilled artisan would understand the extent of the difference, if at all needed, based upon the dilution required to perform the TFF.

[000162] In some embodiments, the platelets or pooled platelets may be acidified to a pH of about 5.5 to about 8.0 prior to TFF or being diluted with the preparation agent. In some embodiments, the method comprises acidifying the platelets to a pH of about 6.5 to about 6.9. In some embodiments, the method comprises acidifying the platelets to a pH of about 6.6 to about 6.8. In some embodiments, the method comprises acidifying the platelets to a pH of about 6.6 to 7.5. In some embodiments, the acidifying comprises adding to the pooled platelets a solution comprising Acid Citrate Dextrose (ACD).

[000163] In some embodiments, the platelets are isolated prior to the step comprising tangential flow filtration (TFF) or being diluted with the preparation agent. In some embodiments, the method further comprises isolating platelets by using centrifugation. In some embodiments, the centrifugation occurs at a relative centrifugal force (RCF) of about 1000 x g to about 2000 x g. In some embodiments, the centrifugation occurs at relative centrifugal force (RCF) of about 1300 x g to about 1800 x g. In some embodiments, the centrifugation occurs at relative centrifugal force (RCF) of about 1500 x g. In some embodiments, the centrifugation occurs for about 1 minute to about 60 minutes. In some embodiments, the centrifugation occurs for about 10 minutes to about 30 minutes. In some embodiments, the centrifugation occurs for about 30 minutes.

[000164] In some embodiments, platelets are isolated, for example in a liquid medium, prior to treating a subject. [000165] In some embodiments, platelets are donor-derived platelets. In some embodiments, platelets are obtained by a process that comprises an apheresis step. In some embodiments, platelets are pooled platelets.

[000166] In some embodiments, platelets are pooled from a plurality of donors. Such platelets pooled from a plurality of donors may be also referred herein to as pooled platelets. In some embodiments, the donors are more than 5, such as more than 10, such as more than 20, such as more than 50, such as up to about 100 donors. In some embodiments, the donors are from about 5 to about 100, such as from about 10 to about 50, such as from about 20 to about 40, such as from about 25 to about 35. Pooled platelets can be used to make any of the compositions described herein. The platelets can be pooled wherein the platelets are donated by human subjects. In some other embodiments, the donor can be a non-human animal. In some embodiments, the donor can be a canine subject. In some embodiments, the donor can be an equine subject. In some embodiments, the donor can be a feline subject.

[000167] In some embodiments, platelets are derived in vitro. In some embodiments, platelets are derived or prepared in a culture. In some embodiments, preparing the platelets comprises deriving or growing the platelets from a culture of megakaryocytes. In some embodiments, preparing the platelets comprises deriving or growing the platelets (or megakaryocytes) from a culture of human pluripotent stem cells (PSCs), including embryonic stem cells (ESCs) and/or induced pluripotent stem cells (iPSCs).

[000168] Accordingly, in some embodiments, platelets or platelet derivatives (e.g., thrombosomes) are prepared prior to treating a subject as described herein. In some embodiments, the platelets or platelet derivatives (e.g., thrombosomes) are lyophilized. In some embodiments, the platelets or platelet derivatives (e.g., thrombosomes) are cryopreserved. For example, in some embodiments, the platelets or platelet derivatives can be cryopreserved in plasma and DMSO (e.g., 3-9% DMSO (e.g., 6% DMSO)). In some embodiments, the platelets or platelet derivatives are cryopreserved as described in U.S. Patent Application Publication No. 2020/0046771 Al, published on February 13, 2020, incorporated herein by reference in its entirety.

[000169] In some embodiments, platelets (e.g., apheresis platelet, platelets isolated from whole blood, pooled platelets, or a combination thereof) form a suspension in a preparation agent comprising a liquid medium at a concentration from 10,000 platelets/pL to 10,000,000 platelets/pL, such as 50,000 platelets/pL to 2,000,000 platelets/pL, such as 100,000 platelets/pL to 500,000 platelets/pL, such as 150,000 platelets/pL to 300,000 platelets/pL, such as 200,000 platelets/pL. [000170] In some embodiments, the method further comprises drying the platelets or platelet derivatives (e.g., thrombosomes). In some embodiments, the drying step comprises lyophilizing the platelets or platelet derivatives (e.g., thrombosomes). In some embodiments, the drying step comprises freeze-drying the platelets or platelet derivatives (e.g., thrombosomes). In some embodiments, the method further comprises rehydrating the platelets or platelet derivatives (e.g., thrombosomes) obtained from the drying step.

[000171] In some embodiments, the platelets or platelet derivatives (e.g., thrombosomes) are cold stored, cryopreserved, or lyophilized (e.g., to produce thrombosomes) prior to use in therapy or in functional assays.

[000172] Any known technique for drying platelets can be used in accordance with the present disclosure, as long as the technique can achieve a final residual moisture content of less than 5%. Preferably, the technique achieves a final residual moisture content of less than 2%, such as 1%, 0.5%, or 0.1%. Non-limiting examples of suitable techniques are freeze-drying (lyophilization) and spray-drying. A suitable lyophilization method is presented in Table LA. Additional exemplary lyophilization methods can be found in U.S. Patent No. 7,811,558, U.S. Patent No. 8,486,617, and U.S. Patent No. 8,097,403. An exemplary spray-drying method includes: combining nitrogen, as a drying gas, with a preparation agent according to the present disclosure, then introducing the mixture into GEA Mobile Minor spray dryer from GEA Processing Engineering, Inc. (Columbia MD, USA), which has a Two-Fluid Nozzle configuration, spray drying the mixture at an inlet temperature in the range of 150°C to 190°C, an outlet temperature in the range of 65 °C to 100°C, an atomic rate in the range of 0.5 to 2.0 bars, an atomic rate in the range of 5 to 13 kg/hr, a nitrogen use in the range of 60 to 100 kg/hr, and a run time of 1 0 to 35 minutes. The final step in spray drying is preferentially collecting the dried mixture. The dried composition in some embodiments is stable for at least six months at temperatures that range from -20°C or lower to 90°C or higher.

[000173] Table LA: Exemplary Lyophilization Protocol

[000174] In some embodiments, the step of drying the platelets or platelet derivatives (e.g., thrombosomes) that are obtained as disclosed herein, such as the step of freeze-drying the platelets and/or platelet derivatives that are obtained as disclosed herein, comprises incubating the platelet and/or platelet derivatives with a lyophilizing agent (e.g., a non-reducing disaccharide). Accordingly, in some embodiments, the methods for preparing platelets and/or platelet derivatives further comprises incubating the platelets with a lyophilizing agent. In some embodiments the lyophilizing agent is a saccharide. In some embodiments the saccharide is a disaccharide, such as a non-reducing disaccharide.

[000175] In some embodiments, the platelets and/or platelet derivatives are incubated with a lyophilizing agent for a sufficient amount of time and at a suitable temperature to incubate the platelets with the lyophilizing agent. Non-limiting examples of suitable lyophilizing agents are saccharides, such as monosaccharides and disaccharides, including sucrose, maltose, trehalose, glucose (e.g., dextrose), mannose, and xylose. In some embodiments, non-limiting examples of lyophilizing agent include scrum albumin, dextran, polyvinyl pyrrolidone (PVP), starch, and hydroxyethyl starch (HES). In some embodiments, exemplary lyophilizing agents can include a high molecular weight polymer. By "high molecular weight" it is meant a polymer having an average molecular weight of about or above 70 kDa and up to 1,000,000 kDa. Non-limiting examples are polymers of sucrose and epichlorohydrin (e.g., polysucrose). In some embodiments, the lyophilizing agent is poly sucrose. Although any amount of high

42

RECTIFIED SHEET (RULE 91 ) ISA/EP molecular weight polymer can be used as a lyophilizing agent, it is preferred that an amount be used that achieves a final concentration of about 3% to 10% (w/v), such as 3% to 7%, for example 6%. In some embodiments, polysucrose is used in the range of 2% to 8%%, or 2.25-7.75%, or 2.5-7.5%, or 2.5-6.5%. In an exemplary embodiment, the composition comprises 3% polysucrose. In another exemplary embodiment, the composition comprises 6% polysucrose. In some embodiments of the composition, wherein the composition comprises polysucrose, the polysucrose is a cationic form of poly sucrose. In some embodiments, the cationic form of polysucrose is diethy laminoethyl (DEAE)-polysucrose. In some embodiments, the polysucrose is an anionic form of polysucrose. In some embodiments, the anionic form of polysucrose is carboxymethyl-polysucrose. In some embodiments of the composition, polysucrose has a molecular weight in the range of 70,000 Da to 400,000 Da. In some embodiments, polysucrose has a molecular weight in the range of 80,000 Da to 350,000 Da, or 100,000 Da to 300,00 Da. In some exemplary embodiments, polysucrose has a molecular weight in the range of 120,000 Da to 200,000 Da. In some exemplary embodiments, polysucrose has a molecular weight of 150,000 Da, or 160,000 Da, or 170,000 Da, or 180,000 Da, 190,000 Da, or 200,000 Da.

[000176] An exemplary saccharide for use in the compositions disclosed herein is trehalose.

Regardless of the identity of the saccharide, it can be present in the composition in any suitable amount. For example, it can be present in an amount of 1 mM to 1 M. In embodiments, it is present in an amount of from 10 mM 10 to 500 mM. In some embodiments, it is present in an amount of from 20 mM to 200 mM. In embodiments, it is present in an amount from 40 mM to 100 mM. In some embodiments, the composition comprises trehalose in the range of 0.4-35%, or 1-35%, or 2-30%, or 1-10%, or 1-5%, or 0.5- 5%. In an exemplary embodiment, the composition comprises 3.5% trehalose.

[000177] In various embodiments, the saccharide is present in different specific concentrations within the ranges recited above, and one of skill in the art can immediately understand the various concentrations without the need to specifically recite each herein. Where more than one saccharide is present in the composition, each saccharide can be present in an amount according to the ranges and particular concentrations recited above.

[000178] In some cases, preparation of thrombosomes further comprises one or more of the procedures described in U.S. Patent Nos. 8,486,617 (such as, e.g., Examples 1 -5) and 8,097,403 (such as, e.g., Examples 1-3), incorporated herein by reference in their entirety. In some cases, a starting material (e.g., one or more donor platelet units) are initially pooled into a common vessel. In some embodiments, a starting material can comprise one or more donor platelet units. In some embodiments, a starting material can comprise donor plasma. The starting material may or may not be acidified with an anti-coagulation

43

RECTIFIED SHEET (RULE 91 ) ISA/EP buffer (i.e. ACD-A) before centrifugation. Plasma can be aspirated off of the platelet pellet after centrifugation. Cell compatible buffer containing cryoprotectants (e.g., a loading buffer, which can be similar to or the same as a preparation agent) can be added to the platelet pellet before resuspending the cells into suspension. Platelets may or may not be diluted to a pre-determined concentration (e.g., 2200 k/ul to 2800 k/ul) with buffer if desired. Platelets in buffer may be incubated between 0 minutes and 240 minutes at an incubation temperature from 18 °C to 37 °C. A lyoprotectant bulking agent (e.g., polysucrose) can be added to the platelets in buffer to achieve a final bulking agent concentration from 1% to 10% w/v (with preference at 6% w/v). The centrifuged processed platelets can then be filled into vials, lyophilized and thermally treated.

Platelet derivatives and microparticles

[000179] Platelet derivatives herein have been observed to have numerous surprising properties, as disclosed in further detail herein. It will be understood, as illustrated in the Examples provided herein, that although platelet derivatives in some aspects and embodiments are in a solid, such as a powder form, the properties of such platelet derivatives can be identified, confirmed, and/or measured when a composition comprising such platelet derivatives is in liquid form.

[000180] A skilled artisan would be well-versed with different techniques that are available for measuring particle sizes of platelets, platelet derivatives or FDPDs, and microparticles. One such technique, in a non-limiting manner, that can be used for measuring particle sizes is flow cytometry. Flow Cytometry is a technique for quantifying characteristics of cells such as cell number, size and complexity, fluorescence, phenotype, and viability. In general, the forward scatter in a flow cytometry is located in line with the laser intercept and is typically considered a measure of the relative cell size. The side scatter is typically located perpendicular to the laser beam intercept and is used to measure the relative complexity of the cell. Commercially available sizing beads can be used to obtain the forward scatter values to calibrate the instrument in order to measure the sizes of the particles.

[000181] Liquid and dried compositions provided herein, in illustrative embodiments those prepared using freeze drying, and more specifically in some embodiments, prepared using methods provided herein, include particles that can be categorized broadly into populations based on at least one physical property, for example, but not limiting to, the size of the particles obtained. In some embodiments, the particles can be categorized into two populations based on size, typically in embodiments where exosomes are not present in detectable quantities, are not resolvable by the instrument analyzing particle size, and/or are not considered particles: For example, a first population comprising larger particles similar, or much more similar in size to in-dated stored platelets, which can be referred to herein as platelet derivatives, FDPDs, platelet-sized particles, a population of platelet derivatives with a size distribution centered around -1,000 nm radius, or ~l,000 nm radius particles, and a second population comprising relatively smaller particles, which can be referred to herein as microparticles, a population of microparticles with a size distribution centered around ~50 nm radius, or —50 nm radius particles (See e.g., FIG. 24A, FIG. 27B, or FIG. 28B where the main population of human in-dated stored platelets is centered at around 1,100 or 1,500 nm radius respectively, with a smaller (i.e. microparticle) peak at around 100 nm radius; and the particles in the FDPD composition (i.e. thrombosomes), which have a -platelet-sized major peak with a radius of approximately 1,100 nm (FIG. 24A) or 1,000 nm (FIG. 27B and FIG. 28B) (i.e. platelet derivatives) and a microparticle radius peak at approximately 50-75 nm).

[000182] A skilled artisan would further understand that the sizes determined for such populations of particles may not always be accurate enough to provide an exact cut-off valuc/rangc between these two particle size peaks. However, the difference in the sizes of the two populations can be resolved reproducibly using known methods, for example, using flow cytometry, or by using a particle/cell counter and approximate size values or size range values can be obtained using such techniques optionally with sizing standards. In some embodiments, a composition comprising platelet derivatives or FDPDs as described herein or prepared according to methods described herein, can have a population comprising platelet derivatives or FDPDs that includes between 95.1% to 99.9% of total particles in the composition, and the rest of the measurable particles, for example above 1 nm radius, can be microparticles. In some embodiments, platelet derivatives or FDPDs in such a composition can have a diameter of at least 0.4pm (i.e., radius of at least 200 nm), and the microparticles in such a composition can have a diameter less than 0.4pm (i.e., radius less than 200 nm). In other embodiments, platelet derivatives or FDPDs in such a composition can have a diameter of at least 0.5pm (i.e., radius of at least 250 nm), and the microparticles in such a composition can have a diameter less than 0.5pm (i.e., radius of less than 250 nm). In some embodiments, the platelet derivatives, or FDPDs can have a diameter of at least 0.4 pm, for example in the range of 0.5pm to 22pm (i.e., radius in the range of 200 nm or 250 nm to 11,000 nm), and the microparticles can have a diameter less than 0.5pm (i.e., less than 250 nm radius), for example in the range of 0.04pm to 0.350pm (i.e., radius in the range of 20 nm to 175 nm). In some embodiments, the platelet derivatives, or FDPDs can have a diameter in the range of 1pm to 18pm (i.e., radius in the range of 500 nm to 9,000 nm), and the microparticles can have a diameter in the range of 0.06pm to 0.2pm (i.e., radius in the range of 30 nm to 100 nm). In some embodiments, the composition comprises platelet derivatives or FDPDs, and microparticles as the only or essentially the only particles present in the composition, optionally or typically other than exosomes, in embodiments where exosomes

45

RECTIFIED SHEET (RULE 91 ) ISA/EP are not present in detectable quantities, are not resolvable by the instrument analyzing particle size, and/or are not considered particles. Of course, a composition as described herein may comprise any specific percentage number, or fraction thereof, of platelet derivatives, FDPDs or microparticles within the ranges discussed herein.

[000183] In some embodiments, the platelets or platelet derivatives (e.g., thrombosomes) have a particle size, for example a diameter, max dimension, or radius of at least about 0.5 pm (e.g., at least about at least about 0.6 pm, at least about 0.7 pm, at least about 0.8 pm, at least about 0.9 pm, at least about 1.0 pm, at least about 1.2 pm, at least about 1.5 pm, at least about 2.0 pm, at least about 2.5 pm, or at least about 5.0 pm). In some embodiments, the particle size, for example the diameter, max dimension, or radius, is less than about 5.0 pm (e.g., less than about 2.5 pm, less than about 2.0 pm, less than about 1.5 pm, less than about 1.0 pm, less than about 0.9 pm, less than about 0.8 pm, less than about 0.7 pm, less than about 0.6 pm, less than about 0.5 pm, less than about 0.4 pm, or less than about 0.3 pm). From this disclosure, it will be apparent that microparticles typically have a size of less than 250 nm radius (i.e. less than 500 nm diameter). In some embodiments, the particle size is from about 0.5 pm to about 5.0 pm (e.g., from about 0.5 pm to about 4.0 pm, from about 0.5 pm to about 2.5 pm, from about 0.6 pm to about 2.0 pm, from about 0.7 pm to about 1.0 pm, from about 0.5 pm to about 0.9 pm, or from about 0.6 pm to about 0.8 pm).

[000184] In some embodiments, at least 50% (e.g., at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, or at least about 99%) of platelets or platelet derivatives (e.g., thrombosomes), have a particle size of at least 0.5 pm, for example in the range of about 0.5 pm to about 25.0 pm, 20.0 pm, 15.0 pm, 12.5 pm, 10.0 pm, or 5.0 pm (e.g., from about 0.5 pm to about 4.0 pm, from about 0.5 pm to about 2.5 pm, from about 0.6 pm to about 2.0 pm, from about 0.7 pm to about 1.0 pm, from about 0.5 pm to about 0.9 pm, or from about 0.6 pm to about 0.8 pm). In some embodiments, at most 99% (e.g., at most about 95%, at most about 80%, at most about 75%, at most about 70%, at most about 65%, at most about 60%, at most about 55%, or at most about 50%) of the platelets or platelet derivatives (e.g., thrombosomes), are in the range of about 0.5 pm to about 5.0 pm (e.g., from about 0.5 pm to about 4.0 pm, from about 0.5 pm to about 2.5 pm, from about 0.6 pm to about 2.0 pm, from about 0.7 pm to about 1.0 pm, from about 0.5 pm to about 0.9 pm, or from about 0.6 pm to about 0.8 pm). In some embodiments, about 50% to about 99% (e.g., about 55% to about 95%, about 60% to about 90%, about 65% to about 85, about 70% to about 80%) of the platelets or platelet derivatives (e.g., thrombosomes) are in the range of about 0.5 pm to about 5.0 pm (e.g., from about 0.5 pm to about 4.0 pm, from about 0.5 pm to about 2.5 pm, from about 0.6 pm to about 2.0 pm, from about 0.7 pm to about 1.0 pm, from about 0.5 pm to about 0.9 pm, or from about 0.6 pm to about 0.8 pm).

[000185] In some illustrative embodiments, a microparticle can be a particle having a particle size (e.g., diameter, max dimension) of less than about 0.5 pm (less than about 0.45 pm or 0.4 pm) In some cases, a microparticle can be a particle having a particle size of about 0.01 pm to about 0.5 pm (e.g., about 0.02 pm to about 0.5 pm).

[000186] Compositions comprising platelets or platelet derivatives (e.g., thrombosomes), such as those prepared according to methods described herein, can have a microparticle content that contributes to less than about 5.0% (e.g., less than about 4.5%, 4.0%, 3.5%, 3.0%, 2.5%, 2.0%, 1.5%, 1.0%, 0.5%, or 0.1%) of the total scattering intensity of all particles from about 1 nm to about 60,000 nm in radius in the composition. In some embodiments, the platelet derivative composition comprises a population of platelet derivatives comprising CD41-positive platelet derivatives, wherein less than 15%, 10%, 7.5%, 5%, 4.5%, 4%, 3.5%, 3%, 2.5%, 2%, 1.5%, 1%, 0.5%, or 0.1% of the CD41-positive platelet derivatives are microparticles having a diameter of less than 1 pm, 0.9 pm, 0.8 pm, 0.7 pm, 0.6 pm, 0.5 pm, 0.4 pm, 0.3 pm, 0.2 pm, or 0.1 pm, which in certain illustrative embodiments are less than 0.5 pm. In some embodiments, the platelet derivative composition comprises a population of platelet derivatives comprising CD42-positive platelet derivatives, wherein less than 15%, 10%, 7.5%, 5%, 4.5%, 4%, 3.5%, 3%, 2.5%, 2%, 1.5%, 1%, 0.5%, or 0. 1% of the CD42 -positive platelet derivatives are microparticles having a diameter of less than 1 pm, 0.9 pm, 0.8 pm, 0.7 pm, 0.6 pm, 0.5 pm, 0.4 pm, 0.3 pm, 0.2 pm, or 0.1 pm, which in certain illustrative embodiments are less than 0.5 pm. In some embodiments, the platelet derivative composition comprises a population of platelet derivatives comprising CD61 -positive platelet derivatives, wherein less than 15%, 10%, 7.5, 5%, 4.5%, 4%, 3.5%, 3%, 2.5%, 2%, 1.5%, 1%, 0.5%, or 0.1% of the CD61-positive platelet derivatives are microparticles having a diameter of less than 1 pm, 0.9 pm, 0.8 pm, 0.7 pm, 0.6 pm, 0.5 pm, 0.4 pm, 0.3 pm, 0.2 pm, or 0.1 pm, which in certain illustrative embodiments are less than 0.5 pm. In some illustrative embodiments, the microparticles have a diameter of less than 0.5 pm. In some embodiments of any of the aspects and embodiments herein that include a platelet derivative composition in a powdered form, the diameter of the microparticles is determined after rehydrating the platelet derivative composition with an appropriate solution. In some embodiments, the amount of solution for rehydrating the platelet derivative composition is equal to the amount of buffer or preparation agent present at the step of freeze-drying. As used herein, a content of microparticles “by scattering intensity” refers to the microparticle content based on the scattering intensity of all particles from about 1 nm to about 60,000 nm in radius in the composition. The microparticle content can be measured by any appropriate method, for example, by dynamic light scattering (DLS). In some cases, the viscosity of a sample used for DLS can be at about 1.060 cP (or adjusted to be so), as this is the approximate viscosity of plasma. In some embodiments, the platelet derivative composition as per any aspects, or embodiments comprises a population of platelet derivatives, and microparticles, wherein the numerical ratio of platelet derivatives to the microparticles is at least 90: 1, 91: 1, 92: 1, 93: 1, 94: 1, 95: 1, 96: 1, 97: 1, 98: 1, or 99: 1. In some embodiments, the platelet derivatives have a diameter in the range of 0.5-2.5 pm, and the microparticles have a diameter less than 0.5 pm.

[000187] Platelets or platelet derivatives (e.g., thrombosomes) as described herein can have cell surface markers. The presence of cell surface markers can be determined using any appropriate method. In some embodiments, the presence of cell surface markers can be determined using binding proteins (e.g., antibodies) specific for one or more cell surface markers and flow cytometry (e.g., as a percent positivity, e.g., using approximately 2.7xl0⁵ thrombosomes/pL; and about 4.8 pL of an anti-CD41 antibody, about 3.3 pL of an anti-CD42 antibody, about 1.3 pL of annexin V, or about 2.4 pL of an anti-CD62 antibody). Non-limiting examples of cell-surface markers include CD41 (also called glycoprotein lib or GPIIb, which can be assayed using e.g., an anti-CD41 antibody), CD42 (which can be assayed using, e.g., an anti-CD42 antibody), CD62 (also called CD62P or P-selectin, which can be assayed using, e.g., an anti- CD62 antibody), phosphatidylserine (which can be assayed using, e.g., annexin V (AV)), and CD47 (which is used in self-recognition; absence of this marker, in some cases, can lead to phagocytosis). The percent positivity of any cell surface marker can be any appropriate percent positivity. For example, platelets or platelet derivatives (e.g., thrombosomes), such as those prepared by methods described herein, can have an average CD41 percent positivity of at least 55% (e.g., at least 60%, at least 65%, at least 67%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, or at least 95%). In some embodiments, at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% platelet derivatives that are positive for CD 41 have a size in the range of 0.5-2.5 pm. In some embodiments, at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% platelet derivatives that are positive for CD 41 have a size in the range of 0.4-2.8 pm. In some embodiments, at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% platelet derivatives that are positive for CD 41 have a size in the range of 0.3-3 pm.

[000188] As another example, platelets or platelet derivatives (e.g., thrombosomes), such as those described herein, can have an average CD42 percent positivity of at least 65% (e.g., at least 67%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, or at least 95%). In some embodiments, platelets or platelet derivatives can have an average CD42 percent positivity of at least 76%, 77%, 78%, or 79%. In some embodiments, platelets or platelet derivatives can have an average CD42 percent positivity in the range of 76-95%, 76-94%, 77-93%, or 78-90%. In some embodiments, at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% platelet derivatives that are positive for CD 42 have a size in the range of 0.5-2.5 pm. In some embodiments, at least 90%, 91%, 92%, 93%, 94%, 95%, 96%,

97%, 98%, or 99% platelet derivatives that are positive for CD 42 have a size in the range of 0.4-2.8 pm.

In some embodiments, at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% platelet derivatives that are positive for CD 42 have a size in the range of 0.3-3 pm.

[000189] As another example, platelets or platelet derivatives (e.g., thrombosomes), such as those prepared by methods described herein, can have an average CD62 percent positivity of at least 10% (e.g., at least 15%, at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least

50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 82%, at least 83%, at least 84%, at least 85%, at least 90%, or at least 95%). In some embodiments, at least 70%,

75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% platelet derivatives that are positive for CD 62 have a size in the range of 0.5-2.5 pm. In some embodiments, at least 70%, 75%, 80%,

85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% platelet derivatives that are positive for

CD 62 have a size in the range of 0.4-2.8 pm. In some embodiments, at least 70%, 75%, 80%, 85%, 90%,

91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% platelet derivatives that are positive for CD 62 have a size in the range of 0.3-3 pm.

[000190] As yet another example, platelets or platelet derivatives (e.g., thrombosomes), such as those prepared by methods described herein, can have an average annexin V positivity of at least 25% (e.g., at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 97%, or at least

99%). In some embodiments, at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% platelet derivatives that are positive for annexin V have a size in the range of 0.5-2.5 pm. In some embodiments, at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% platelet derivatives that are positive for annexin V have a size in the range of 0.4-2.8 pm. In some embodiments, at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% platelet derivatives that are positive for annexin V have a size in the range of 0.3-3 pm.

[000191] In some embodiments, the platelet derivatives as described herein are activated to a maximum extent such that in the presence of an agonist, the platelet derivatives are not able to show an increase in the platelet activation markers on them as compared to the level of the platelet activation markers which were present prior to the exposure with the agonist. In some embodiments, the platelet derivatives as described herein show an inability to increase expression of a platelet activation marker in the presence of an agonist as compared to the expression of the platelet activation marker in the absence of an agonist. In some embodiments, the agonist is selected from the group consisting of collagen, epinephrine, ristocetin, arachidonic acid, adenosine di -phosphate, and thrombin receptor associated protein (TRAP). In some embodiments, the platelet activation marker is selected from the group consisting of Annexin V, and CD 62. In some embodiments, the platelet derivatives as described herein show an inability to increase expression of Annexin V in the presence of TRAP. An increased amount of the platelet activation markers on the platelets indicates the state of activeness of the platelets. However, in some embodiments, the platelet derivatives as described herein are not able to increase the amount of the platelet activation markers on them even in the presence of an agonist. This property indicates that the platelet derivatives as described herein are activated to a maximum extent. In some embodiments, the property can be beneficial where maximum activation of platelets is required, because the platelet derivatives as described herein is able to show a state of maximum activation in the absence of an agonist.

[000192] As another example, platelets or platelet derivatives (e.g., thrombosomes), such as those prepared by methods described herein, can have an average CD47 percent positivity of at least about 8% (e.g., at least about 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, or 55%).

[000193] Glycoprotein VI (GPVI) is a platelet receptor for collagen, and the binding of collagen to GVPI activates the platelet. Receptor binding can be noticeably reduced in thrombosomes compared to fresh platelets. Without being bound by any particular theory, it is believed that the manufacturing process is blocking or destroying some copies of this receptor in thrombosomes, possibly to a reduction in collagen binding in thrombosomes relative to fresh platelets.

[000194] Platelets or platelet derivatives (e.g., thrombosomes) as described herein can have fibrinogen associated with the cell membrane. Aggregation of activated platelets is mediated by the formation of the GPIIb/IIIa complex, which can bind to fibrinogen (also called Factor 1) and form a clot. GPIIb/IIIa is a platelet fibrinogen receptor also known as CD41/CD61 complex. The GPIIb/IIIa clone PAC-1 binds to the active form of the GPIIb/IIIa. Without being bound by any particular theory, it is believed that the presence of fibrinogen on the cell membrane may be indicative of platelets or platelet derivatives (e.g., thrombosomes) capable of forming clots. Similarly, without being bound by any particular theory, it is believed that a lack of binding by anti-PACl antibodies to the platelets or platelet derivatives (e.g., thrombosomes), such as those prepared by methods described herein, can be indicative of fibrinogen bound to the active form of GPIIb/GPIIIa, as PAC- 1 binds to the same complex. In some cases, platelets or platelets derivatives (e.g., thrombosomes), such as those prepared by methods described herein, can have a greater amount of bound fibrinogen when they retain a higher amount of residual plasma. In some embodiments of a platelet derivative composition as described herein, the platelet derivatives can have an amount of fibrinogen on their surface that is greater than that present on the surface of resting platelets, activated platelets, or lyophilized fixed platelets. In some embodiments, the platelet derivatives have at least 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100% higher fibrinogen on their surface as compared to resting platelets, or activated platelets, or fixed platelets. In some embodiments, the platelet derivatives when analyzed for the binding of anti-fibrinogen antibody to the platelet derivatives using flow cytometry exhibit at least 2 folds higher mean fluorescent intensity (MFI) in the absence of an agonist as compared to the MFI of binding of anti-fibrinogen antibody to the lyophilized fixed platelets. In some embodiments, the platelet derivatives when analyzed for the binding of anti-fibrinogen antibody to the platelet derivatives using flow cytometry exhibit at least 10, 15, 20, 25, 30, 35, or 40 folds higher mean fluorescent intensity (MFI) in the absence of an agonist as compared to the MFI of binding of anti-fibrinogen antibody to the fixed platelets. In some embodiments, the greater amount of fibrinogen present on the surface of the platelet derivatives as described herein as compared to that of lyophilized fixed platelets is beneficial. Without being bound by any particular theory, it is believed that the higher amount of fibrinogen on the cell membrane of the platelet derivatives (e.g., thrombosomes) as compared to that of lyophilized fixed platelets can make the platelet derivatives superior in terms of its ability to form clots as compared to lyophilized fixed platelets.

[000195] Von Willebrand factor (vWF) is a multimeric glycoprotein that plays a major role in blood coagulation. vWF serves as a bridging molecule that promotes platelet binding to sub-endothelium and other platelets, thereby promoting platelet adherence and aggregation. vWF also binds to collagens to facilitate clot formation at sites of injury. In some embodiments, the platelet derivatives as described herein have the presence of von Willebrand factor (vWF) on their surface at a level that is greater than that on the surface of resting platelets, activated platelets, or lyophilized fixed platelets. In some embodiments, the platelet derivatives have the presence of von Willebrand factor (vWF) on their surface at a level that is at least 10%, 20%, 25%, 30%, 50%, 60%, 70%, 80%, 90%, or 100% higher than on the surface of resting platelets, or lyophilized fixed platelets. In some embodiments, the platelet derivatives when analyzed for the binding of anti-von Willebrand factor (vWF) antibody to the platelet derivatives using flow cytometry exhibits at least 1.5 folds, 2 folds, or 3 folds, or 4 folds higher mean fluorescent intensity (MFI) in the absence of an agonist as compared to the MFI of binding of anti-vWF antibody to the resting platelets, or lyophilized fixed platelets. In some embodiments, the platelet derivatives when analyzed for the binding of anti-von Willebrand factor (vWF) antibody to the platelet derivatives using flow cytometry exhibits 2-4 folds, or 2.5-3.5 higher mean fluorescent intensity (MFI) in the absence of an agonist as compared to the MFI of binding of anti-vWF antibody to the resting platelets, or lyophilized fixed platelets. [000196] Thrombospondin is a glycoprotein secreted from the a-granules of platelets upon activation. In the presence of divalent cations, the secreted protein binds to the surface of the activated platelets and is responsible for the endogenous lectin-like activity associated with activated platelets. In some embodiments, the platelet derivatives have the presence of thrombospondin (TSP-1) on their surface at a level that is greater than that presence on the surface of resting platelets, activated platelets, or lyophilized fixed platelets. In some embodiments, the platelet derivatives have the presence of thrombospondin (TSP- 1) on their surface at a level that is at least 10%, 20%, 25%, 30%, 50%, 60%, 70%, 80%, 90%, or 100% higher than on the surface of resting platelets, or lyophilized fixed platelets. In some embodiments, the platelet derivatives have the presence of thrombospondin (TSP-1) on their surface at a level that is more than 100% higher than on the surface of resting platelets, or lyophilized fixed platelets. In some embodiments, the platelet derivatives when analyzed for the binding of anti-thrombospondin (TSP) antibody to the platelet derivatives using flow cytometry exhibit at least 2 folds, 5 folds, 7 folds, 10 folds, 20 folds, 30 folds, 40 folds, 50 folds, 60 folds, 70 folds, 80 folds, 90 folds, or 100 folds higher mean fluorescent intensity (MFI) in the absence of an agonist as compared to the MFI of binding of anti-TSP antibody to the resting platelets. In some embodiments, the platelet derivatives when analyzed for the binding of anti-thrombospondin (TSP) antibody to the platelet derivatives using flow cytometry exhibit at least 2 folds, 5 folds, 7 folds, 10 folds, 20 folds, 30 folds, or 40 folds higher mean fluorescent intensity (MFI) in the absence of an agonist as compared to the MFI of binding of anti-TSP antibody to the lyophilized fixed platelets. In some embodiments, the platelet derivatives when analyzed for the binding of anti-thrombospondin (TSP) antibody to the platelet derivatives using flow cytometry exhibit 10-800 folds, 20-800 folds, 100-700 folds, 150-700 folds, 200-700 folds, or 250-500 folds higher mean fluorescent intensity (MFI) in the absence of an agonist as compared to the MFI of binding of anti-TSP antibody to the resting platelets. In some embodiments, the platelet derivatives when analyzed for the binding of anti-thrombospondin (TSP) antibody to the platelet derivatives using flow cytometry exhibit at least 2 folds, 5 folds, 7 folds, 10 folds, 20 folds, 30 folds, or 40 folds higher mean fluorescent intensity (MFI) in the absence of an agonist as compared to the MFI of binding of anti-TSP antibody to the active platelets. In some embodiments, the platelet derivatives when analyzed for the binding of anti- thrombospondin (TSP) antibody to the platelet derivatives using flow cytometry exhibit 2-40 folds, 5-40 folds, 5-35 folds, 10-35 folds, or 10-30 folds higher mean fluorescent intensity (MFI) in the absence of an agonist as compared to the MFI of binding of anti-TSP antibody to the active platelets.

[000197] Platelets or platelet derivatives (e.g., thrombosomes) as described herein can be capable of generating thrombin, for example, when in the presence of a reagent containing tissue factor and phospholipids. For example, in some cases, platelets or platelet derivatives (e.g., thrombosomes) (e.g., at a concentration of about 4.8xl0³ particles/pL) as described herein can generate a thrombin peak height (TPH) of at least 25 nM (e.g., at least 30 nM, 35 nM, 40 nM, 45 nM, 50 nM, 52 nM, 54 nM, 55 nM, 56 nM, 58 nM, 60 nM, 65 nM, 70 nM, 75 nM, or 80 nM) when in the presence of a reagent containing tissue factor (e.g., at 0.25 pM, 0.5 pM, 1 pM, 2 pM, 5 pM or 10 pM) and optionally phospholipids. For example, in some cases, platelets or platelet derivatives (e.g., thrombosomes) (e.g., at a concentration of about 4.8xl0³ particles/|iL) as described herein can generate a TPH of about 25 nM to about 100 nM (e.g., about 25 nM to about 50 nM, about 25 to about 75 nM, about 50 to about 100 nM, about 75 to about 100 nM, about 35 nM to about 95 nM, about 45 to about 85 nM, about 55 to about 75 nM, or about 60 to about 70 nM) when in the presence of a reagent containing tissue factor and (e.g., at 0.25 pM, 0.5 pM, 1 pM, 2 pM, 5 pM or 10 pM) and optionally phospholipids. In some cases, platelets or platelet derivatives (e.g., thrombosomes) (e.g., at a concentration of about 4.8xl0³ particles/pL) as described herein can generate a TPH of at least 25 nM (e.g., at least 30 nM, 35 nM, 40 nM, 45 nM, 50 nM, 52 nM, 54 nM, 55 nM, 56 nM, 58 nM, 60 nM, 65 nM, 70 nM, 75 nM, or 80 nM) when in the presence of PRP Reagent (cat# TS30.00 from Thrombinoscope), for example, using conditions comprising 20 pL of PRP Reagent and 80 pL of a composition comprising about 4.8 x 10³ particles/pL of platelets or platelet derivatives (e.g., thrombosomes). In some cases, platelets or platelet derivatives (e.g., thrombosomes) (e.g., at a concentration of about 4.8xl0³ particles/pL) as described herein can generate a TPH of about 25 nM to about 100 nM (e.g., about 25 nM to about 50 nM, about 25 to about 75 nM, about 50 to about 100 nM, about 75 to about 100 nM, about 35 nM to about 95 nM, about 45 to about 85 nM, about 55 to about 75 nM, or about 60 to about 70 nM) when in the presence of PRP Reagent (cat# TS30.00 from Thrombinoscope), for example, using conditions comprising 20 pL of PRP Reagent and 80 pL of a composition comprising about 4.8 x 10³ particles/pL of platelets or platelet derivatives (e.g., thrombosomes).

[000198] Platelets or Platelet derivatives (e.g., thrombosomes) as described herein can be capable of generating thrombin, for example, when in the presence of a reagent containing tissue factor and phospholipids. For example, in some cases, platelets or platelet derivatives (e.g., thrombosomes) can have a potency of at least 1.2 (e.g., at least 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, or 2.5) thrombin generation potency units (TGPU) per 10⁶ particles. For example, in some cases, platelets or platelet derivatives (e.g., thrombosomes) can have a potency of between 1.2 and 2.5 TPGU per 10⁶ particles (e.g., between 1.2 and 2.0, between 1.3 and 1.5, between 1.5 and 2.25, between 1.5 and 2.0, between 1.5 and 1.75, between 1.75 and 2.5, between 2.0 and 2.5, or between 2.25 and 2.5 TPGU per 10⁶ particles). TPGU can be calculated as follows: TGPU/million particles = [TPH in nM]*[Potency Coefficient in IU/(nM)] / [0.576 million particles in the well]. Similarly, the Potency Coefficient for a

53

RECTIFIED SHEET (RULE 91 ) ISA/EP sample of thrombin can be calculated as follows: Potency Coefficient = Calculated Calibrator Activity (IU)/ Effective Calibrator Activity (nM). In some cases, the calibrator activity can be based on a WHO international thrombin standard.

[000199] Platelets or platelet derivatives (e.g., thrombosomes) as described herein can be capable of clotting, as determined, for example, by using a total thrombus-formation analysis system (T-TAS®). In some cases, platelets or platelet derivatives as described herein, when at a concentration of at least 70xl0³ particles/pL (e.g., at least 73 xlO³, 100 xlO³, 150 xlO³, 173 xlO³, 200 xlO³, 250 xlO³, or 255 xlO³ particles/pL) can result in a T-TAS occlusion time (e.g., time to reach kPa of 80) of less than 14 minutes (e.g., less than 13.5, 13, 12.5, 12, 11.5, or 11 minutes), for example, in platelet-reduced citrated whole blood. In some cases, platelets or platelet derivatives as described herein, when at a concentration of at least 70xl0³ particles/pL (e.g., at least 73 xlO³, 100 xlO³, 150 xlO³, 173 xlO³, 200 xlO³, 250 xlO³, or 255 xlO³ particles/pL) can result in an area under the curve (AUC) of at least 1300 (e.g., at least 1380, 1400, 1500, 1600, or 1700), for example, in platelet-reduced citrated whole blood.

[000200] Platelets or platelet derivatives (e.g., thrombosomes) as described herein can be capable of thrombin-induced trapping in the presence of thrombin. In some cases, platelets or platelet derivatives (e.g., thrombosomes) as described herein can have a percent thrombin-induced trapping of at least 5% (e.g., at least 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 67%, 70%, 75%, 85%_; 90%, or 99%) in the presence of thrombin. In some cases, platelets or platelet derivatives (e.g., thrombosomes) as described herein can have a percent thrombin-induced trapping of about 25% to about 100% (e.g., about 25% to about 50%, about 25% to about 75%, about 50% to about 100%, about 75% to about 100%, about 40% to about 95%, about 55% to about 80%, or about 65% to about 75%) in the presence of thrombin. Thrombin-induced trapping can be determined by any appropriate method, for example, light transmission aggregometry. Without being bound by any particular theory, it is believed that the thrombin-induced trapping is a result of the interaction of fibrinogen present on the surface of the platelet derivatives with thrombin.

[000201] Platelets or platelet derivatives (e.g., thrombosomes) as described herein can be capable of coaggregating, for example, in the presence of an aggregation agonist, and fresh platelets. Non-limiting examples of aggregation agonists include, collagen, epinephrine, ristocetin, arachidonic acid, adenosine di -phosphate, and thrombin receptor associated protein (TRAP). In some cases, platelets or platelet derivatives (e.g., thrombosomes) as described herein can have a percent co-aggregation of at least 5% (e.g., at least 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 67%, 70%, 75%, 85%. 90%, or 99%) in the presence of an aggregation agonist, and fresh platelets. In some cases, platelets or platelet derivatives (e.g., thrombosomes) as described herein can have a percent co-aggregation of about 25% to about 100% (e.g., about 25% to about 50%, about 25% to about 75%, about 50% to about 100%, about 75% to about 100%, about 40% to about 95%, about 55% to about 80%, or about 65% to about 75%) in the presence of an aggregation agonist. Percent co-aggregation can be determined by any appropriate method, for example, light transmission aggregometry.

[000202] Platelet derivative compositions in certain illustrative embodiments herein, comprise a population of platelet derivatives having a reduced propensity to aggregate under aggregation conditions comprising an agonist but no fresh platelets, compared to the propensity of fresh platelets and/or activated to aggregate under these conditions. Platelets or platelet derivatives (e.g., thrombosomes) as described herein in illustrative embodiments, display a reduced propensity to aggregate under aggregation conditions comprising an agonist but no fresh platelets, compared to the propensity of fresh platelets and/or activated to aggregate under these conditions. It is noteworthy that aggregation of platelet derivatives is different from co-aggregation in that aggregation conditions typically do not include fresh platelets, whereas co-aggregation conditions include fresh platelets. Exemplary aggregation and coaggregation conditions are provided in the Examples herein. Thus, in some embodiments, the platelet derivatives as described herein have a higher propensity to co-aggregate in the presence of fresh platelets and presence of an agonist, while having a reduced propensity to aggregate in the absence of fresh platelets and presence of an agonist, compared to the propensity of fresh platelets to aggregate under these conditions. In some embodiments, a platelet derivative composition comprises a population of platelet derivatives having a reduced propensity to aggregate, wherein no more than 1%, 2%, 3%, 4%, 5%, 7.5%, 10%, 12.5%, 15%, 17.5%, 20%, 22.5%, or 25% of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets, in illustrative embodiments no fresh platelets. In some embodiments, the population of platelet derivatives aggregate in the range of 0-1%, 0- 2%, 0-3%, 0-4%, 0-5%, 0-7.5%, 0-10%, 2-30%, 5-25%, 10-30%, 10-25%, or 12.5-25%, and in illustrative embodiments 0-1% or 0 to about 1%, of the platelet derivatives under aggregation conditions comprising an agonist but no platelets, in illustrative embodiments no fresh platelets. In these and other illustrative embodiments the agonist is other than arachidonic acid. It will be understood that if an aggregation reaction control sample produces a background aggregation above 0% then aggregation values/ranges for FDPDs disclosed herein would be increased by the background value obtained with the control sample. Thus, if a background aggregation produced using a control sample was 1%, then the above ranges would be increased by l% (e.g., 1-2%, 1-3%, 1-4%, 1-5%, 1-6%, 1-8.5%, and 1-11% etc.). Accordingly, in some embodiments, the values and ranges provided herein for aggregation are values above background values, for example obtained using a control sample or no sample, and thus can be referred to control-corrected, or control-adjusted aggregation values. In some embodiments, a platelet derivative composition comprises a population of platelet derivatives having a reduced propensity to aggregate, such that less than 1/5, 1/10, or 1/20 of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets, compared to platelet rich plasma, in illustrative embodiments prepared from fresh platelets.

[000203] Compositions comprising platelets or platelet derivatives (e.g., thrombosomes) as described herein can have appropriate conditions and amounts of cellular substrates and/or metabolites, such as pH, pCO₂, pO₂, HCO3 concentration, total carbon dioxide (TCO₂), sO₂, and lactate concentration. Lactate can be the products of glycolysis. Without being bound by any particular theory, a starting material can have high lactate concentration because it has been stored ex vivo, respirating and performing glycolysis, for a period of time (e.g., about 3 days) by the time of manufacturing. For example, in some cases, the pH can be about 5.5 to about 8.0 (e.g., about 6.0 to about 7.4, about 6.9 to about 7.5, or about 7.0 to about 7.3). As another example, the pCO₂ can be about 10 to about 20 mmHg (e.g., about 10 to about 15 mmHg, about 15 to about 20 mmHg, or about 17 to about 19 mmHg). The pO₂can be about 140 to about 165 mmHg (e.g., about 140 to about 150 mmHg, about 150 to about 160 mmHg, or about 160 to about 165 mmHg). The HCOs concentration can be about 4.5 to about 6.5 mmol/L (e.g., about 5.0 to about 6.0 mmol/L). The total carbon dioxide can be about 4 to about 8 mmol/L (e.g., about 5 to about 7 mmol/L). The sO₂ can be at least about 98% (e.g., at least about 99%). The lactate concentration can be less than about 2.0 mmol/L (e.g., less than 1.5 mmol/L or 1.0 mmol/L). The lactate concentration can be about 0.4 to about 1.3 mmol/L (e.g., about 0.5 to about 0.6 mmol/L, about 0.5 to about 1.0 mmol/L, or about 0.8 to about 1.3 mmol/L).

Membrane Integrity of the platelet derivatives

[000204] Platelet derivatives in certain illustrative aspects and embodiments herein are surrounded by a compromised plasma membrane. In these illustrative aspects and embodiments, the platelet derivatives lack an integrated membrane around them. Instead, the membrane has pores on them that are larger than pores observed on living cells. Not to be limited by theory, it is believed that in embodiments where platelet derivatives have a compromised membrane, such platelet derivatives have a reduced ability to, or are unable to transduce signals from the external environment into a response inside the particle that are typically transduced in living platelets. A compromised membrane can be identified through a platelet derivative’s inability to retain more than 50% of lactate dehydrogenase (LDH) as compared to fresh platelets, or cold stored platelets, or cryopreserved platelets. In some embodiments, the platelet derivatives are incapable of retaining more than 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, or 75% of

56

RECTIFIED SHEET (RULE 91 ) ISA/EP lactate dehydrogenase as compared to lactate dehydrogenase retained in fresh platelets, or cold stored platelets, or cryopreserved platelets. In some embodiments, the platelet derivatives exhibit an increased permeability to antibodies. In some embodiments, the antibodies can be IgG antibodies. The increased permeability can be identified by targeting IgG antibodies against a stable intracellular antigen. One nonlimiting type of stable intracellular antigen is P tubulin. The compromised membrane of the platelet derivatives can also be determined by flow cytometry studies.

[000205] Platelet or platelet derivatives (e.g., thrombosomes) as described herein can retain some metabolic activity, for example, as evidenced by lactate dehydrogenase (LDH) activity. In some cases, platelets or platelet derivatives (e.g., thrombosomes) as described herein can retain at least about 10% (e.g., at least about 12%, 15%, 20%, 25%, 30%, 35%, 40%, or 45%) of the LDH activity of donor apheresis platelets. Without being bound by any particular theory, it is believed that the addition of increasing amounts of polysucrose increases the amount of LDH activity remained (e.g., products of a preparation agent with 8% poly sucrose have more retained LDH activity than products of a preparation agent with 4% polysucrose). Similarly unbound by any particular theory, it is believed that thermal treatment of a lyophilized composition comprising platelets or platelet derivatives (e.g., thrombosomes) increases the amount of LDH activity retained. As another example, metabolic activity can be evidenced by retained esterase activity, such as the ability of the cells to cleave the acetate groups on carboxyfluorescein diacetate succinimidyl ester (CFDASE) to unmask a fluorophore.

Pathogen reduction

[000206] The reduction of pathogens is generally desirable in blood products. Without being bound by any particular theory, it is believed that some methods of pathogen reduction can cause the formation of microparticles in the treated blood product. One method of pathogen reduction involves the use of a photosensitive nucleic acid-intercalating compound to alter the nucleic acids of pathogens upon illumination with an appropriate wavelength. The INTERCEPT® system (made by Cerus) uses amotosalen, a nucleic acid intercalating compound that forms cross-links in nucleic acid upon illumination with UVA.

Starting material comprising platelets or a platelet composition

[000207] A final blood product (e.g., platelets, cryopreserved platelets, freeze-dried platelets (e.g., thrombosomes)) as described herein can be prepared by any appropriate method. A final blood product (e.g., platelets, cryopreserved platelets, freeze-dried platelets (e.g., thrombosomes)) as described herein can be prepared by a method as disclosed herein. In some embodiments described herein, a final blood product can be a composition that includes platelets and an aqueous medium. In some embodiments, a final blood product can be the result of freeze-drying a composition that includes platelets and an aqueous medium, as described herein. In some embodiments, a final blood product can be prepared using tangential flow filtration (TFF) of a starting material (e.g., an unprocessed blood product (e.g., donor apheresis material (e.g., pooled donor apheresis material)), or a partially processed blood product (e.g., a blood product that has undergone filtration)). In some embodiments, a final blood product can be prepared using centrifugation of a starting material (e.g., an unprocessed blood product (e.g., donor apheresis material (e.g., pooled donor apheresis material)), or a partially processed blood product (e.g., a blood product that has undergone filtration)). It will be appreciated that while the methods described herein are generally described in the context of a starting material being apheresis material, other materials, such as platelets cultured in vitro, or whole blood, may be used. In some cases, platelets may be isolated from whole blood (e.g. pooled whole blood).

[000208] A starting material can be any appropriate starting material. In some embodiments, a starting material can have a protein concentration of about 60 to about 80 mg/mL. In some embodiments, a protein concentration can be based on the protein concentration in the plasma of whole blood. In some embodiments, a protein concentration can be based on the protein concentration of donor apheresis plasma. In some embodiments, a starting material can be donor blood product (e.g., whole blood or fractionated blood). In some embodiments, the starting material can be pooled donor blood product (e.g., pooled whole blood or pooled fractionated blood). In some embodiments, a starting material can include donor apheresis plasma. In some embodiments, a starting material can be derived from donor apheresis plasma. As used herein, “donor apheresis plasma” can refer to the plasma component of apheresis material, whether or not the material contains platelets or other blood cells.

[000209] In some embodiments, a starting material can be donor apheresis material (e.g., donor platelets or a pool of donor platelets). In some embodiments, a starting material is positive for one or more of: HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies based on a regulatory agency- approved assay (e.g., an FDA cleared assay). In some embodiments, starting material can test positive for HLA Class I antibodies in a regulatory agency approved assay (e.g., an FDA cleared assay). In some embodiments, a starting material can test positive for HLA Class II antibodies in a regulatory agency approved assay (e.g., an FDA cleared assay). In some embodiments, starting material can test positive for HNA antibodies in a regulatory agency approved assay (e.g., an FDA cleared assay). A regulatory agency approved assay can be any appropriate regulatory agency approved assay. In some embodiments, a regulatory agency approved test can be the LABSCREEN™ Mixed by One Lambda. In some implementations, a regulatory agency approved test can be carried out using a LUMINEX® 100/200 or a LUMINEX® XY and the HLA FUSION™ software.

[000210] In some embodiments, a starting material can undergo a pathogen reduction step, for example, a nucleic acid intercalating compound that forms cross-links in nucleic acid upon illumination with UVA.

[000211] In some embodiments, a starting material (e.g., one or more units of donor platelets) can be initially pooled into a common vessel. The starting material may or may not be initially diluted with an acidified washing buffer (e.g., a control buffer). Without being bound by any particular theory, it is believed that washing with an acidified washing buffer can reduce platelet activation during processing. In some cases, a starting material can undergo two general processing pathways; either washed with control buffer (e.g. using TFF) until a desired residual component is reached (e.g., a percentage of residual donor plasma) before being concentrated to a final concentration; or the starting material can be concentrated to a final concentration before being washed with control buffer (e.g., using TFF) until a desired residual component is reached (e.g., a percentage of residual donor plasma). TFF processed material can then be filled into vials, lyophilized and thermally treated.

Different steps in processing of a starting material, and TFF

[000212] In some embodiments, the method can include an initial dilution step, for example, a starting material (e.g., an unprocessed blood product (e.g., donor apheresis material (e.g., pooled donor apheresis material)) can be diluted with a preparation agent (e.g., any of the preparation agents described herein) to form a diluted starting material. In some cases, the initial dilution step can include dilution with a preparation agent with a mass of preparation agent equal to at least about 10% of the mass of the starting material (e.g., at least about 15%, 25%, 50%, 75%, 100%, 150%, or 200% of the mass of the starting material. In some embodiments, an initial dilution step can be carried out using the TFF apparatus.

[000213] In some embodiments, the method can include concentrating (e.g., concentrating platelets) (e.g., concentrating a starting material or a diluted starting material) to form a concentrated platelet composition. For example, concentrated can include concentrating to a about 1000 x 10³to about 4000 x I0³ platelets/pL (e.g., about 1000 x 10³ to about 2000 x 10³, about 2000 x 10³ to about 3000 x 10³, or about 4000 x 10³ platelets/pL). In some embodiments, a concentration step can be carried out using the TFF apparatus. [000214] The concentration of platelets or platelet derivatives (e.g., thrombosomes) can be determined by any appropriate method. For example, a counter can be used to quantitate concentration of blood cells in suspension using impedance (e.g., a Beckman Coulter AcT 10 or an AcT diff 2).

[000215] In some embodiments, TFF can include diafdtering (sometimes called “washing”) of a starting material, a diluted starting material, a concentrated platelet composition, or a combination thereof. In some embodiments, diafdtering can include washing with at least 2 (e.g., at least 3, 4, 5, 6, 7, 8, 9, 10, or more) diavolumes. In some embodiments, TFF can include buffer exchange. In some embodiments, a buffer can be used in TFF. A buffer can be any appropriate buffer. In some embodiments, the buffer can be a preparation agent (e.g., any of the preparation agents described herein). In some embodiments, the buffer can be the same preparation agent as was used for dilution. In some embodiments, the buffer can be a different preparation than was used for dilution. In some embodiments, a buffer can include a lyophilizing agent, including a buffering agent, a base, a loading agent, optionally a salt, and optionally at least one organic solvent such as an organic solvent selected from the group consisting of ethanol, acetic acid, acetone, acetonitrile, dimethylformamide, dimethyl sulfoxide, dioxane, methanol, n-propanol, isopropanol, tetrahydrofuran (THF), N-methyl pyrrolidone, dimethylacetamide (DMAC), or combinations thereof. A buffering agent can be any appropriate buffering agent. In some embodiments, a buffering agent can be HEPES ((4-(2 -hydroxyethyl)- 1 -piperazineethane sulfonic acid). A base can be any appropriate base. In some embodiments, a base can be sodium bicarbonate. In some embodiments, a saccharide can be a monosaccharide. In some embodiments, a loading agent can be a saccharide. In some embodiments, a saccharide can include sucrose, maltose, trehalose, glucose (e.g., dextrose), mannose, or xylose. In some embodiments, a monosaccharide can be trehalose. In some embodiments, the loading agent can include polysucrose. A salt can be any appropriate salt. In some embodiments, a salt can be selected from the group consisting of sodium chloride (NaCl), potassium chloride (KC1), or a combination thereof.

[000216] In some embodiments, a membrane with a pore size of about 0. 1 pm to about 1 pm (e.g., about 0.1 pm to about 1 pm, about 0.1 pm to about 0.5 pm, about 0.2 to about 0.45 pm, about 0.45 to about 1 pm, about 0. 1 pm, about 0.2 pm, about 0.45 pm, about 0.65 pm, or about 1 pm) can be used in TFF. A membrane can be made from any appropriate material. In some cases, a membrane can be a hydrophilic membrane. In some embodiments, a membrane can be a hydrophobic membrane. In some embodiments, a membrane with a nominal molecular weight cutoff (NMWCO) of at least about 100 kDa (e.g., at least about 200 kDa, 300 kDa, 500 kDa, or 1000 kDa) can be used in TFF. The TFF can be performed with any appropriate pore size within the range of 0.1 pm to 1.0 pm with the aim of reducing the microparticles content in the composition and increasing the content of platelet derivatives in the composition. A skilled artisan can appreciate the required optimization of the pore size in order to retain the platelet derivatives and allow the microparticles to pass through the membrane. The pore size in illustrative embodiments, is such that the microparticles pass through the membrane allowing the TFF- treated composition to have less than 5% microparticles. The pore size in illustrative embodiments is such that a maximum of platelet derivatives gets retained in the process allowing the TFF-treated composition to have a concentration of the platelet derivatives in the range of 100 x 10³ to 20,000 x 10³. The pore size during the TFF process can be exploited to obtain a higher concentration of platelet derivatives in the platelet derivative composition such that a person administering the platelet derivatives to a subject in need has to rehydrate/reconstitute fewer vials, therefore, being efficient with respect to time and effort during the process of preparing such platelet derivatives for a downstream procedure, for example a method of treating provided herein. TFF can be performed at any appropriate temperature. In some embodiments, TFF can be performed at a temperature of about 20 °C to about 37 °C (e.g., about 20 °C to about 25 °C, about 20 °C to about 30 °C, about 25 °C to about 30 °C, about 30 °C to about 35 °C, about 30 °C to about 37 °C, about 25 °C to about 35 °C, or about 25 °C to about 37 °C). In some embodiments, TFF can be carried out at a flow rate (e.g., a circulating flow rate) of about 100 ml/min to about 800 ml/min (e.g., about 100 to about 200 ml/min, about 100 to about 400 ml/min, about 100 to about 600 ml/min, about 200 to about 400 ml/min, about 200 to about 600 ml/min, about 200 to about 800 ml/min, about 400 to about 600 ml/min, about 400 to about 800 ml/min, about 600 to about 800 ml/min, about 100 ml/min, about 200 ml/min, about 300 ml/min, about 400 ml/min, about 500 ml/min, about 600 ml/min, about 700 ml/min, or about 800 ml/min).

[000217] In some embodiments, TFF can be performed until a particular endpoint is reached, forming a TFF-treated composition. An endpoint can be any appropriate endpoint. In some embodiments, an endpoint can be a percentage of residual plasma (e.g., less than or equal to about 50%, 40%, 30%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, or 0. 1% of residual plasma). In some embodiments, an endpoint can be a relative absorbance at 280 nm (A280). For example, an endpoint can be an A280 (e.g., using a path length of 0.5 cm) that is less than or equal to about 50% (e.g., less than or equal to about 40%, 30%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, or 0.1%) of the A280 (e.g., using a path length of 0.5 cm) prior to TFF (e.g., of a starting material or of a diluted starting material). In some embodiments, an A280 can be relative to a system that measures 7.5% plasma = 1.66 AU. In some embodiments, an instrument to measure A280 can be configured as follows: a 0.5cm gap flow cell can be attached to the filtrate line of the TFF system. The flow cell can be connected to a photometer with fiber optics cables attached to each side of the flow cell (light source cable and light detector cable). The flow cell can be made with a silica glass lens on each side of the fiber optic cables. Apart from the relative protein concentration of proteins in the aqueous medium, the protein concentration in the aqueous medium can also be measured in absolute terms. In some embodiments, the protein concentration in the aqueous medium is less than or equal to 15%, or 14%, or 13%, or 12%, or 11%, or 10%, or 9%, or 8%, or 7%, or 6%, or 5%, or 4%, or 3%, or 2%, or 1%, or 0.1%, or 0.01%. In some exemplary embodiments, the protein concentration is less than 3% or 4%. In some embodiments, the protein concentration is in the range of 0.01-15%, or 0.1-15%, or 1-15%, or 1-10%, or 0.01-10%, or 3-12%, or 5-10% in the TFF-treated composition. In some embodiments, an endpoint can be an absolute A280 (e.g., using a path length of 0.5 cm). For example, an endpoint can be an A280 that is less than or equal to 2.50 AU, 2.40 AU, 2.30 AU, 2.20 AU, 2.10 AU, 2.0 AU, 1.90 AU, 1.80 AU, or 1.70 AU (e.g., less than or equal to 1.66, 1.6, 1.5, 1.4, 1.3, 1.2, 1.1, 1.0, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, or 0.1 AU) (e.g., using a path length of 0.5 cm). In some embodiments, a percentage of residual plasma, a relative A280, or an A280 can be determined based on the aqueous medium of a composition comprising platelets and an aqueous medium. In some embodiments, a percentage of residual plasma can be determined based on a known correlation to an A280. In some embodiments, an endpoint can be a platelet concentration, as TFF can include concentration or dilution of a sample (e.g., using a preparation agent). For example, an endpoint can be a platelet concentration of at least about 2000 x 10³ platelets/pU (e.g., at least about 2050 x 10³, 2100 x 10³, 2150 x 10³, 2200 x 10³, 2250 x 10³, 2300 x 10³, 2350 x 10³, 2400 x 10³, 2450 x 10³, or 2500 x 10³ platelets/pU). As another example, an endpoint can be a platelet concentration of about 1000 x 10³to about 2500 platelets/pU (e.g., about 1000 x 10³ to about 2000 x 10³, about 1500 x 10³ to about 2300 x 10³, or about 1700 x 10³to about 2300 x 10³ plate lets/pU). In some embodiments, an endpoint can be a concentration of platelets in the TFF-treated composition are at least 100 x 10³ platclets/pL. 200 x 10³ platclets/pL. 400 x 10³ platclets/pL. 1000 x 10³ platclets/pL. 1250 x 10³ platclets/pL. 1500 x 10³ platclets/pL. 1750 x 10³ platclets/pL. 2000 x 10³ platclets/pL. 2250 x 10³ platclets/pL. 2500 x 10³ platclets/pL. 2750 x 10³ platclets/pL. 3000 x 10³ platclets/pL. 3250 x 10³ platclets/pL. 3500 x 10³ platclets/pL. 3750 x 10³ platclets/pL. 4000 x 10³ platclets/pL. 4250 x 10³ platclets/pL. 4500 x 10³ platclets/pL. 4750 x 10³ platclets/pL. 5000 x 10³ platelets/pU, 5250 x 10³ platelets/pU, 5500 x 10³ platelets/pU, 5750 x 10³ platelets/pU, 6000 x 10³ platelets/pU, 7000 x 10³ platelets/pU, 8000 x 10³ platelets/pU, 9000 x 10³ platelets/pU, 10,000 x 10³ platelets/pU, 11,000 x 10³ platelets/pU, 12,000 x 10³ platelets/pU, 13,000 x 10³ platelets/pU, 14,000 x 10³ platelets/pU, 15,000 x 10³ platelets/pU, 16,000 x 10³ platelets/pU, 17,000 x 10³ platelets/pU, 18,000 x 10³ platelets/pU, 19,000 x 10³ platelets/pU, 20,000 x 10³ platclets/pL. In some embodiments, the platelets or platelet derivatives in the TFF-treated composition is in the range of 100 x 10³ - 20,000 x 10³ platelets/pU, or 1000 x 10³ - 20,000 x 10³ platelets/pU, or 1000 x 10³ - 10,000 x 10³ platelets/pL, or 500 x IO³ - 5,000 x IO³ platelets/pL, or 1000 x IO³ - 5,000 x IO³ platelets/pL, or 2000 x IO³ - 8,000 x IO³ platelets/pL, or 10,000 x IO³ - 20,000 x IO³ platelets/pL, or 15,000 x IO³ - 20,000 x IO³ platelets/pL.

[000218] In some embodiments, an endpoint can include more than one criterion (e.g., a percentage of residual plasma and a platelet concentration, a relative A280 and a platelet concentration, or an absolute A280 and a platelet concentration).

[000219] Typically, a TFF -treated composition is subsequently lyophilized, optionally with a thermal treatment step, to form a final blood product (e.g., platelets, cryopreserved platelets, freeze-dried platelets (e.g., thrombosomes)). However, in some cases, a TFF-treated composition can be considered to be a final blood product.

[000220] In some embodiments, a blood product can be prepared using centrifugation of a blood product (e.g., an unprocessed blood product (e.g., donor apheresis material (e.g., pooled donor apheresis material)), or a partially processed blood product (e.g., a blood product that has undergone TFF)). In some embodiments, a blood product can be prepared without centrifugation of a blood product (e.g., an unprocessed blood product (e.g., donor apheresis material), or a partially processed blood product (e.g., a blood product that has undergone TFF)). Centrifugation can include any appropriate steps. In some embodiments, centrifugation can include a slow acceleration, a slow deceleration, or a combination thereof. In some embodiments, centrifugation can include centrifugation at about 1400 x g to about 1550 x g (e.g., about 1400 to about 1450 x g, about 1450 to about 1500 x g, or 1500 to about 1550 x g, about 1400 x g, about 1410 x g, about 1430 x g, about 1450 x g, about 1470 x g, about 1490 x g, about 1500 x g, about 1510 x g, about 1530 x g, or about 1550 x g). In some embodiments, the duration of centrifugation can be about 10 min to about 30 min (e.g., about 10 to about 20 min, about 20 to about 30 min, about 10 min, about 20 min, or about 30 min).

[000221 ] In some embodiments, a final blood product can be prepared using both TFF and centrifugation (e.g., TFF followed by centrifugation or centrifugation followed by TFF).

[000222] Also provided herein are compositions prepared by any of the methods described herein.

[000223] In some embodiments, a composition as described herein can be analyzed at multiple points during processing. In some embodiments, a starting material (e.g., donor apheresis material (e.g., pooled donor apheresis material)) can be analyzed for antibody content (e.g., HLA or HNA antibody content). In some embodiments, a starting material (e.g., donor apheresis material (e.g., pooled donor apheresis material)) can be analyzed for protein concentration (e.g., by absorbance at 280 nm (e.g., using a path length of 0.5 cm)). In some embodiments, a composition in an intermediate step of processing (e.g., when protein concentration reduced to less than or equal to 75% (e.g., less than or equal to 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or less) of the protein concentration of an unprocessed blood product) can be analyzed for antibody content (e.g., HLA or HNA antibody content). In some embodiments, the antibody content (e.g., HLA or HNA antibody content) of a blood product in an intermediate step of processing can be at least 5% reduced (e.g., 10%, 20%, 30%, 40%, 50%, 60%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or more, reduced) compared to the antibody content of the starting material. In some embodiments, a final blood product (e.g., (e.g., platelets, cryopreserved platelets, freeze-dried platelets (e.g., thrombosomes)) can be analyzed for antibody content (e.g., HLA or HNA antibody content). In some embodiments described herein, a final blood product can be a composition that includes platelets and an aqueous medium. In some embodiments, the antibody content (e.g., HLA or HNA antibody content) of a final blood product (e.g., (e.g., platelets, cryopreserved platelets, freeze-dried platelets (e.g., thrombosomes)) can be at least 5% reduced (e.g., 10%, 20%, 30%, 40%, 50%, 60%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or more, reduced) compared to the antibody content of the starting material. In some embodiments, a final blood product can have no detectable level of an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies. In some embodiments, the aqueous medium of a composition as described herein can be analyzed as described herein.

[000224] In some embodiments, a composition as described herein can be analyzed at multiple points during processing. In some embodiments, donor apheresis plasma can be analyzed for antibody content (e.g., HLA or HNA antibody content). In some embodiments, donor apheresis plasma can be analyzed for protein concentration (e.g., by absorbance at 280 nm). In some embodiments, a composition in an intermediate step of processing (e.g., when protein concentration reduced to less than or equal to 75% (e.g., less than or equal to 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or less) of the protein concentration of an unprocessed blood product) can be analyzed for antibody content (e.g., HLA or HNA antibody content). In some embodiments, the antibody content (e.g., HLA or HNA antibody content) of a blood product in an intermediate step of processing can be at least 5% reduced (e.g., 10%, 20%, 30%, 40%, 50%, 60%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or more, reduced) compared to the antibody content of donor apheresis plasma. In some embodiments, a final blood product (e.g., platelets, cryopreserved platelets, freeze-dried platelets (e g., thrombosomes)) can be analyzed for antibody content (e.g., HLA or HNA antibody

64

RECTIFIED SHEET (RULE 91 ) ISA/EP content). In some embodiments described herein, a final blood product can be a composition that includes platelets and an aqueous medium. In some embodiments, the antibody content (e.g., HLA or HNA antibody content) of a final blood product (e.g., platelets, cryopreserved platelets, freeze-dried platelets (e.g., thrombosomes)) can be at least 5% reduced (e.g., 10%, 20%, 30%, 40%, 50%, 60%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or more, reduced) compared to the antibody content of donor apheresis plasma. In some embodiments, a final blood product can have no detectable level of an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies. In some embodiments, the aqueous medium of a composition as described herein can be analyzed as described herein.

[000225] The protein concentration of a blood product can be measured by any appropriate method. In some embodiments, the protein concentration of a blood product can be measured using absorbance at 280 nm.

[000226] The antibody content (e g., HLA or HNA antibody content) of a blood product can be measured by any appropriate method.

[000227] In some embodiments, a FLOWPRA™ Screening or a LAB Screen Multi test kits from One Lambda, Thermo Fisher Scientific can be used as a method of HLA detection. Raw materials can be tested prior to the TFF or centrifugation processes to determine a baseline level of class I and II antibodies for Human Leukocyte Antigen (HLA) and Human Neutrophil Antigens (HNA). Testing can be repeated after processing by centrifugation or TFF to measure the removal of HLA and HNA. Additional testing points can be performed throughout the TFF procedure to maintain in-process control. Post-lyophilization and annealing, random samples can be selected from a batch and qualitative HLA/HNA antibody testing can be performed to ensure reduction and compliance with current FDA testing and acceptance requirements.

[000228] In some embodiments, the antibody content (e.g., HLA or HNA antibody content) of two blood products can be compared by determining the percentage of beads positive for a marker (e.g., HLA or HNA coated beads bound to HLA or HNA antibodies, respectively). Any appropriate comparative method can be used. In some embodiments, the antibody content of two blood products can be compared using a method as described herein. In some embodiments, such a method can be carried out as follows. An aliquot of plasma (e.g., about 1 mL) platelet-poor plasma can be obtained. In some embodiments, an aliquot of filtered (e.g., using a 0.2 pm filter) platelet-poor plasma (PPP) (e.g., about 1 mL) can be obtained. Beads coated with Class I HLA and/or beads coated with Class II HLA can be added to the

65

RECTIFIED SHEET (RULE 91 ) ISA/EP plasma (e.g., about 5 pL of each type of bead to about 20 pL of PPP) to form a mixture of PPP and beads. The mixture of PPP and beads can be vortexed. The mixture of PPP and beads can be incubated to form an incubated mixture. Any appropriate incubation conditions can be used. For example, in some embodiments, incubation can occur for a time (e.g., for about 30 minutes) at a temperature (e.g., at room temperature) with other conditions (e.g., in the dark) to form an incubated mixture. In some embodiments, incubation can include agitation (e.g., gentle rocking). The beads in the incubated mixture can be washed using any appropriate conditions. In some embodiments, the beads in the incubated mixture can be washed with a wash buffer. Washed beads can be separated from the incubated mixture by any appropriate method. In some embodiments, the washed beads can be separated by centrifugation (e.g., at 9,000 x g for 2 minutes) to obtain pelleted beads. In some embodiments, the washing step can be repeated. The beads can be resuspended to form a bead solution. An antibody (e.g., an antibody that will bind to the assayed antibody content (e.g., HLA or HNA antibody content)) conjugated to a detectable moiety can be added to the bead solution (e.g., an algG conjugated to a fluorescent reporter, such as FITC). The antibody can be incubated with the bead solution under any appropriate conditions. In some embodiments, the antibody can be incubated for a time (e.g., for about 30 minutes) at a temperature (e.g., at room temperature) with other conditions (e.g., in the dark) to form labeled beads. Labeled beads can be washed to remove unbound antibody conjugated to a detectable moiety. The labeled beads can be washed using any appropriate conditions. In some embodiments, the labeled beads can be washed with a wash buffer. Washed labeled beads can be separated by any appropriate method. In some embodiments, the washed labeled beads can be separated by centrifugation (e.g., at 9,000 g for 2 minutes) to obtain pelleted labeled beads. In some embodiments, the washing step can be repeated. Labeled beads can be detected by any appropriate method. In some embodiments, labeled beads can be detected by flow cytometry. In some embodiments, detection can include measurement of the percentage of beads that are positive for the detectable moiety as compared to a negative control. In some embodiments, a negative control can be prepared as above, using a PPP sample that is known to be negative for antibodies (e.g. HLA Class I, HLA Class II, or HNA antibodies).

[000229] In some embodiments, a blood product (e.g., platelets, cryopreserved platelets, freeze-dried platelets (e.g., thrombosomes)) can be analyzed at multiple points during processing. In some embodiments, a starting material (e.g., donor apheresis material) can be analyzed to determine the percent of positive beads (e.g., HLA or HNA coated beads). In some embodiments, a starting material (e.g., donor apheresis material) can be analyzed for protein concentration (e.g., by absorbance at 280 nm). In some embodiments, a blood product in an intermediate step of processing (e.g., when protein concentration reduced to less than or equal to 75% (e.g., less than or equal to 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or less) of the protein concentration of a starting material) can be analyzed to determine the percent of positive beads (e.g., HLA or HNA coated beads). In some embodiments, a blood product in an intermediate step of processing (e.g., when protein concentration reduced to less than or equal to 75% (e.g., less than or equal to 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or less) of the protein concentration of a starting material) can be analyzed to determine the percent of positive beads (e.g., HLA or HNA coated beads). In some embodiments, the percent of positive beads (e.g., HLA or HNA coated beads) from a blood product in an intermediate step of processing can be at least 5% reduced (e.g., 10%, 20%, 30%, 40%, 50%, 60%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or more, reduced) compared to the percent of positive beads from a starting material. In some embodiments, the percent of positive beads (e.g., HLA or HNA coated beads) from a blood product in an intermediate step of processing can be less than or equal to 75% (e.g., less than or equal to 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or less) of the total amount of beads. In some embodiments, a final blood product (e.g., platelets, cryopreserved platelets, freeze-dried platelets (e.g., thrombosomes)) can be analyzed to determine the percent of positive beads (e.g., HLA or HNA coated beads). In some embodiments, the percent of positive beads (e.g., HLA or HNA coated beads) from a final blood product (e.g., platelets, cryopreserved platelets, freeze-dried platelets (e.g., thrombosomes)) can be at least 5% reduced (e.g., 10%, 20%, 30%, 40%, 50%, 60%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or more, reduced) compared to the percent of positive beads from a starting material. In some embodiments, the percent of positive beads (e.g., HLA or HNA coated beads) from a final blood product can be less than or equal to 75% (e.g., less than or equal to 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or less) of the total amount of beads. In some embodiments, the aqueous medium of a composition as described herein can be analyzed as described herein.

[000230] In some embodiments, a blood product (e.g., platelets, cryopreserved platelets, freeze-dried platelets (e.g., thrombosomes)) can be analyzed at multiple points during processing. In some embodiments, donor apheresis plasma can be analyzed to determine the percent of positive beads (e.g., HLA or HNA coated beads). In some embodiments, donor apheresis plasma can be analyzed for protein concentration (e.g., by absorbance at 280 nm). In some embodiments, a blood product in an intermediate step of processing (e.g., when protein concentration reduced to less than or equal to 75% (e.g., less than or equal to 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or less) of the protein concentration of a starting material) can be analyzed to determine the percent of positive beads (e g., HLA or HNA coated beads). In some embodiments, a blood

67

RECTIFIED SHEET (RULE 91 ) ISA/EP product in an intermediate step of processing (e.g., when protein concentration reduced to less than or equal to 75% (e.g., less than or equal to 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or less) of the protein concentration of a starting material) can be analyzed to determine the percent of positive beads (e.g., HLA or HNA coated beads). In some embodiments, the percent of positive beads (e.g., HLA or HNA coated beads) from a blood product in an intermediate step of processing can be at least 5% reduced (e.g., 10%, 20%, 30%, 40%, 50%, 60%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or more, reduced) compared to the percent of positive beads from donor apheresis plasma. In some embodiments, the percent of positive beads (e.g., HLA or HNA coated beads) from a blood product in an intermediate step of processing can be less than or equal to 75% (e.g., less than or equal to 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or less) of the total amount of beads. In some embodiments, a final blood product (e.g., (e.g., platelets, cryopreserved platelets, freeze-dried platelets (e.g., thrombosomes)) can be analyzed to determine the percent of positive beads (e.g., HLA or HNA coated beads). In some embodiments, the percent of positive beads (e.g., HLA or HNA coated beads) from a final blood product (e.g., (e.g., platelets, cryopreserved platelets, freeze-dried platelets (e.g., thrombosomes)) can be at least 5% reduced (e.g., 10%, 20%, 30%, 40%, 50%, 60%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or more, reduced) compared to the percent of positive beads from donor apheresis material. In some embodiments, the percent of positive beads (e.g., HLA or HNA coated beads) from a final blood product can be less than or equal to 75% (e.g., less than or equal to 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%,

1%, or less) of the total amount of beads. In some embodiments, the aqueous medium of a composition as described herein can be analyzed as described herein.

[000231 ] A percentage of positive beads can be determined using any appropriate method. In some embodiments, positive beads can be determined compared to a negative control sample. A negative control sample can be any appropriate negative control sample. In some embodiments, a negative control sample can be used to determine positivity gating such that less than a certain percentage (e.g., between about 0.01% and about 1% (e.g., about 0.01% to about 0.05%, about 0.05% to about 0.1%, about 0.1% to about 0.5%, about 0.5% to about 1%, about 0.01%, about 0.05%, about 0. 1%, about 0.5%, or about 1%)) of the negative control sample is present within the positivity gate. In some embodiments, a negative control sample can be a buffer (e.g., PBS). In some embodiments, a negative control sample can be a synthetic plasma composition. In some embodiments, a negative control sample can be a blood product known to be negative for the assayed antibodies (e.g., HLA or HNA antibodies). [000232] Also provided herein is a method of reducing the percentage of an antibody (e.g., a HLA antibody (e.g., a HLA Class I antibody or a HLA Class II antibody) or a HNA antibody) in a composition (e.g., a blood product) comprising platelets, the method comprising filtering the composition by tangential flow filtration. Also provided herein is a method of reducing the amount of an antibody (e.g., a HLA antibody (e.g., a HLA Class I antibody or a HLA Class II antibody) or a HNA antibody) in a composition (e.g., a blood product) comprising platelets, the method comprising filtering the composition by tangential flow filtration. Also provided herein is a method of reducing the percentage of beads positive for an antibody (e.g., a HLA antibody (e.g., a HLA Class I antibody or a HLA Class II antibody) or a HNA antibody) in a composition (e.g., a blood product) comprising platelets, the method comprising filtering the composition by tangential flow filtration.

[000233] Also provided herein is a method of reducing the percentage of an antibody (e.g., a HLA antibody (e.g., a HLA Class I antibody or a HLA Class II antibody) or a HNA antibody) in a composition (e.g., a blood product) comprising platelets, the method comprising filtering the composition by centrifugation. Also provided herein is a method of reducing the amount of an antibody (e.g., a HLA antibody (e.g., a HLA Class I antibody or a HLA Class II antibody) or a HNA antibody) in a composition (e.g., a blood product) comprising platelets, the method comprising filtering the composition by centrifugation. Also provided herein is a method of reducing the percentage of beads positive for an antibody (e.g., a HLA antibody (e.g., a HLA Class I antibody or a HLA Class II antibody) or a HNA antibody) in a composition (e.g., a blood product) comprising platelets, the method comprising filtering the composition by centrifugation.

[000234] In some embodiments of any of the methods described herein, the amount of an antibody (e.g., a HLA antibody (e.g., a HLA Class I antibody or a HLA Class II antibody) or a HNA antibody) in a composition (e.g., a blood product) can be reduced to below a reference level. A reference level can be any appropriate reference level. In some embodiments of any of the methods described herein, the percentage of beads positive an antibody (e.g., a HLA antibody (e.g., a HLA Class I antibody or a HLA Class II antibody) or a HNA antibody) in a composition (e.g., a blood product) can be reduced as compared to the blood product before undergoing the methods described herein. A percentage of beads positive for an antibody can be reduced by any appropriate amount. In some embodiments, a percentage of beads positive for an antibody can be reduced by at least 5% (e.g., reduced by at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, or more) compared to the blood product before undergoing any of the methods described herein. [000235] In some embodiments, a composition as described herein can undergo any appropriate additional processing steps. In some embodiments, a composition as described herein can be freeze-dried. In some embodiments, freeze-dried platelets can be thermally treated (e.g., at about 80 °C for about 24 hours).

[000236] For example, in some embodiments, a composition can be cryopreserved or freeze-dried. In some embodiments, a first composition (e.g., a composition comprising platelets and an aqueous medium as described herein) can be treated with a mixture. In some embodiments, a mixture can include a lyophilizing agent, including a base, a loading agent, and optionally at least one organic solvent such as an organic solvent selected from the group consisting of ethanol, acetic acid, acetone, acetonitrile, dimethylformamide, dimethyl sulfoxide, dioxane, methanol, n-propanol, isopropanol, tetrahydrofuran (THF), N-methyl pyrrolidone, dimethylacetamide (DMAC), or combinations thereof, to form a second composition comprising platelets. In some embodiments, a loading agent can be a saccharide. In some embodiments, a saccharide can be a monosaccharide. In some embodiments, a saccharide can be sucrose, maltose, trehalose, glucose (e.g., dextrose), mannose, or xylose. In some embodiments, the loading agent can be polysucrose.

[000237] In some embodiments, a first composition or a second composition can be dried. In some embodiments, a first composition or a second composition can be dried with a cryoprotectant. In some embodiments, a cryoprotectant can include a saccharide, optionally a base, and optionally at least one organic solvent such as an organic solvent selected from the group consisting of ethanol, acetic acid, acetone, acetonitrile, dimethylformamide, dimethyl sulfoxide, dioxane, methanol, n-propanol, isopropanol, tetrahydrofuran (THF), N-methyl pyrrolidone, dimethylacetamide (DMAC), or combinations thereof to form a third composition. In some embodiments, a cryoprotectant can be polysucrose.

[000238] In some embodiments, a first composition or a second composition can be freeze-dried. In some embodiments, a first composition or a second composition can be freeze-dried with a cryoprotectant. In some embodiments, a cryoprotectant can include a saccharide, optionally a base, and optionally at least one organic solvent such as an organic solvent selected from the group consisting of ethanol, acetic acid, acetone, acetonitrile, dimethylformamide, dimethyl sulfoxide, dioxane, methanol, n- propanol, isopropanol, tetrahydrofuran (THF), N-methyl pyrrolidone, dimethylacetamide (DMAC), or combinations thereof to form a fourth composition. In some embodiments freeze-drying can occur at a temperature of about -40 °C to about 5 °C. In some embodiments, freeze-drying can occur over a gradient (e.g., about -40 °C to about 5 °C). In some embodiments, a secondary drying step can be carried out (e.g., at about 20 °C to about 40 °C). [000239] Also provided herein are blood products (e.g., platelets, cryopreserved platelets, freeze-dried platelets (e.g., thrombosomes)) produced by any of the methods described herein.

[000240] In some embodiments, the percentage of beads positive for an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies, as determined for a composition as described herein by flow cytometry using beads coated with Class I HLAs, Class II HLAs, or HNAs, respectively, is reduced by at least 10% (e.g., at least 20%, 30%, 40%, 50%, 60%, 70%, 75%, 80%, 85%, 90%, 95%, or 99%) as compared to a similar composition not prepared by a process comprising tangential flow filtration of a composition comprising platelets, centrifugation of a composition comprising platelets, or a combination thereof.

[000241] In some embodiments, the percentage of beads positive for HLA Class I antibodies, as determined for a composition as described herein by flow cytometry using beads coated with Class I HLAs, is reduced by at least 10% (e.g., at least 20%, 30%, 40%, 50%, 60%, 70%, 75%, 80%, 85%, 90%, 95%, or 99%) as compared to a similar composition not prepared by a process comprising tangential flow fdtration of a composition comprising platelets, centrifugation of a composition comprising platelets, or a combination thereof.

[000242] In some embodiments, the percentage of beads positive for HLA Class II antibodies, as determined for a composition as described herein by flow cytometry using beads coated with Class II HLAs, is reduced by at least 10% (e.g., at least 20%, 30%, 40%, 50%, 60%, 70%, 75%, 80%, 85%, 90%, 95%, or 99%) as compared to a similar composition not prepared by a process comprising tangential flow filtration of a composition comprising platelets, centrifugation of a composition comprising platelets, or a combination thereof.

[000243] In some embodiments, the percentage of beads positive for HNA antibodies, as determined for a composition as described herein by flow cytometry using beads coated with HNAs, is reduced by at least 10% (e.g., at least 20%, 30%, 40%, 50%, 60%, 70%, 75%, 80%, 85%, 90%, 95%, or 99%) as compared to a similar composition not prepared by a process comprising tangential flow fdtration of a composition comprising platelets, centrifugation of a composition comprising platelets, or a combination thereof.

[000244] Within the process provided herein for making the compositions provided herein, optional addition of a lyophilizing agent can be the last step prior to drying. However, in some embodiments, the lyophilizing agent can be added at the same time or before other components of the composition, such as a salt, a buffer, optionally a cryoprotectant, or other components. In some embodiments, the lyophilizing agent is added to a preparation agent, thoroughly mixed to form a drying solution, dispensed into a drying vessel (e.g., a glass or plastic serum vial, a lyophilization bag), and subjected to conditions that allow for drying of a TFF-treated composition to form a dried composition.

[000245] In various embodiments, the lyophilization bag is a gas-permeable bag configured to allow gases to pass through at least a portion or all portions of the bag during the processing. The gas-permeable bag can allow for the exchange of gas within the interior of the bag with atmospheric gas present in the surrounding environment. The gas-permeable bag can be permeable to gases, such as oxygen, nitrogen, water, air, hydrogen, and carbon dioxide, allowing gas exchange to occur in the compositions provided herein. In some embodiments, the gas-permeable bag allows for the removal of some of the carbon dioxide present within an interior of the bag by allowing the carbon dioxide to permeate through its wall. In some embodiments, the release of carbon dioxide from the bag can be advantageous to maintaining a desired pH level of the composition contained within the bag.

[000246] In some embodiments, the container of the process herein is a gas-permeable container that is closed or sealed. In some embodiments, the container is a container that is closed or sealed and a portion of which is gas-permeable. In some embodiments, the surface area of a gas-permeable portion of a closed or sealed container (e.g., bag) relative to the volume of the product being contained in the container (hereinafter referred to as the “SA/V ratio”) can be adjusted to improve pH maintenance of the compositions provided herein. For example, in some embodiments, the SA/V ratio of the container can be at least about 2.0 cm²/mL (e.g., at least about 2. 1 cm²/mL , at least about 2.2 cm²/mL , at least about 2.3 cm²/mL , at least about 2.4 cm²/mL , at least about 2.5 cm²/mL , at least about 2.6 cm²/mL , at least about 2.7 cm²/mL , at least about 2.8 cm²/mL , at least about 2.9 cm²/mL , at least about 3.0 cm²/mL , at least about 3.1 cm²/mL , at least about 3.2 cm²/mL , at least about 3.3 cm²/mL , at least about 3.4 cm²/mL , at least about 3.5 cm²/mL , at least about 3.6 cm²/mL , at least about 3.7 cm²/mL , at least about 3.8 cm²/mL , at least about 3.9 cm²/mL , at least about 4.0 cm²/mL , at least about 4.1 cm²/mL , at least about 4.2 cm²/mL , at least about 4.3 cm²/mL , at least about 4.4 cm²/mL , at least about 4.5 cm²/mL , at least about 4.6 cm²/mL , at least about 4.7 cm²/mL , at least about 4.8 cm²/mL , at least about 4.9 cm²/mL , or at least about 5.0 cm²/mL . In some embodiments, the SA/V ratio of the container can be at most about 10.0 cm²/mL (e.g., at most about 9.9 cm²/mL , at most about 9.8 cm²/mL , at most about 9.7 cm²/mL , at most about 9.6 cm²/mL , at most about 9.5 cm²/mL , at most about 9.4 cm²/mL , at most about 9.3 cm²/mL , at most about 9.2 cm²/mL , at most about 9. 1 cm²/mL , at most about 9.0 cm²/mL , at most about 8.9 cm²/mL , at most about 8.8 cm²/mL , at most about 8.7 cm²/mL , at most about 8.6 , cm²/mL at most about 8.5 cm²/mL , at most about 8.4 cm²/mL , at most about 8.3 cm²/mL , at most about 8.2 cm²/mL , at most about 8.1 cm²/mL , at most about 8.0 cm²/mL , at most about 7.9 cm²/mL , at most about 7.8 cm²/mL , at most about 7.7 cm²/mL , at most about 7.6 cm²/mL , at most about 7.5 cm²/mL , at most about 7.4 cm²/mL , at most about 7.3 cm²/mL , at most about 7.2 cm²/mL , at most about 7. 1 cm²/mL , at most about 6.9 cm²/mL , at most about 6.8 cm²/mL , at most about 6.7 cm²/mL , at most about 6.6 cm²/mL , at most about 6.5 cm²/mL , at most about 6.4 cm²/mL , at most about 6.3 cm²/mL , at most about 6.2 cm²/mL , at most about 6. 1 cm²/mL , at most about 6.0 cm²/mL , at most about 5.9 cm²/mL , at most about 5.8 cm²/mL , at most about 5.7 cm²/mL , at most about 5.6 cm²/mL , at most about 5.5 cm²/mL , at most about 5.4 cm²/mL , at most about 5.3 cm²/mL , at most about 5.2 cm²/mL , at most about 5.1 cm²/mL , at most about 5.0 cm²/mL , at most about 4.9 cm²/mL , at most about 4.8 cm²/mL , at most about 4.7 cm²/mL , at most about 4.6 cm²/mL , at most about 4.5 cm²/mL , at most about 4.4 cm²/mL , at most about 4.3 cm²/mL , at most about 4.2 cm²/mL , at most about 4. 1 cm²/mL , or at most about 4.0 cm²/mL . In some embodiments, the SA/V ratio of the container can range from about 2.0 to about 10.0 cm²/mL (e.g., from about 2.1 cm²/mL to about 9.9 cm²/mL , from about 2.2 cm²/mL to about 9.8 cm²/mL , from about 2.3 cm²/mL to about 9.7 cm²/mL , from about 2.4 cm²/mL to about 9.6 cm²/mL , from about 2.5 cm²/mL to about 9.5 cm²/mL , from about 2.6 cm²/mL to about 9.4 cm²/mL , from about 2.7 cm²/mL to about 9.3 cm²/mL , from about 2.8 cm²/mL to about 9.2 cm²/mL , from about 2.9 cm²/mL to about 9. 1 cm²/mL , from about 3.0 cm²/mL to about 9.0 cm²/mL , from about 3.1 cm²/mL to about 8.9 cm²/mL , from about 3.2 cm²/mL to about 8.8 cm²/mL , from about 3.3 cm²/mL to about 8.7 cm²/mL , from about 3.4 cm²/mL to about 8.6 cm²/mL , from about 3.5 cm²/mL to about 8.5 cm²/mL , from about 3.6 cm²/mL to about 8.4 cm²/mL , from about 3.7 cm²/mL to about 8.3 cm²/mL , from about 3.8 cm²/mL to about 8.2 cm²/mL , from about 3.9 cm²/mL to about 8. 1 cm²/mL , from about 4.0 cm²/mL to about 8.0 cm²/mL , from about 4. 1 cm²/mL to about 7.9 cm²/mL , from about 4.2 cm²/mL to about 7.8 cm²/mL , from about 4.3 cm²/mL to about 7.7 cm²/mL , from about 4.4 cm²/mL to about 7.6 cm²/mL , from about 4.5 cm²/mL to about 7.5 cm²/mL , from about 4.6 cm²/mL to about 7.4 cm²/mL , from about 4.7 cm²/mL to about 7.3 cm²/mL , from about 4.8 cm²/mL to about 7.2 cm²/mL , from about 4.9 cm²/mL to about 7.1 cm²/mL , from about 5.0 cm²/mL to about 6.9 cm²/mL , from about 5.1 cm²/mL to about 6.8 cm²/mL , from about 5.2 cm²/mL to about 6.7 cm²/mL , from about 5.3 cm²/mL to about 6.6 cm²/mL , from about 5.4 cm²/mL to about 6.5 cm²/mL , from about 5.5 cm²/mL to about 6.4 cm²/mL , from about 5.6 cm²/mL to about 6.3 cm²/mL , from about 5.7 cm²/mL to about 6.2 cm²/mL , or from about 5.8 cm²/mL to about 6.1 cm²/mL .

[000247] Gas-permeable closed containers (e.g., bags) or portions thereof can be made of one or more various gas-permeable materials. In some embodiments, the gas-permeable bag can be made of one or more polymers including fluoropolymers (such as polytetrafluoroethylene (PTFE) and perfluoroalkoxy (PFA) polymers), polyolefins (such as low-density polyethylene (LDPE), high-density polyethylene (HDPE)), fluorinated ethylene propylene (FEP), polystyrene, polyvinylchloride (PVC), silicone, and any combinations thereof.

[000248] In some embodiments, dried platelets or platelet derivatives (e.g., thrombosomes) can undergo heat treatment. Heating can be performed at a temperature above about 25°C (e.g., greater than about 40°C, 50°C, 60°C, 70°C, 80°C or higher). In some embodiments, heating is conducted between about 70°C and about 85°C (e.g., between about 75°C and about 85°C, or at about 75°C or 80 °C). The temperature for heating can be selected in conjunction with the length of time that heating is to be performed. Although any suitable time can be used, typically, the lyophilized platelets are heated for at least 1 hour, but not more than 36 hours. Thus, in embodiments, heating is performed for at least 2 hours, at least 6 hours, at least 12 hours, at least 18 hours, at least 20 hours, at least 24 hours, or at least 30 hours. For example, the lyophilized platelets can be heated for 18 hours, 19 hours, 20 hours, 21 hours, 22 hours, 23 hours, 24 hours, 25 hours, 26 hours, 27 hours, 28 hours, 29 hours, or 30 hours. Non-limiting exemplary combinations include: heating the dried platelets or platelet derivatives (e.g., thrombosomes) for at least 30 minutes at a temperature higher than 30°C; heating the dried platelets or platelet derivatives (e.g., thrombosomes) for at least 10 hours at a temperature higher than 50°C; heating the dried platelets or platelet derivatives (e.g., thrombosomes) for at least 18 hours at a temperature higher than 75°C; and heating the dried platelets or platelet derivatives (e.g., thrombosomes) for 24 hours at 80°C. In some embodiments, heating can be performed in sealed container, such as a capped vial. In some embodiments, a sealed container be subjected to a vacuum prior to heating. The heat treatment step, particularly in the presence of a cryoprotectant such as albumin or polysucrose, has been found to improve the stability and shelf-life of the freeze-dried platelets. Indeed, advantageous results have been obtained with the particular combination of serum albumin or polysucrose and a post-lyophilization heat treatment step, as compared to those cryoprotectants without a heat treatment step. A cryoprotectant (e.g., sucrose) can be present in any appropriate amount (e.g. about 3% to about 10% by mass or by volume of the platelets or platelet derivatives (e.g., thrombosomes).

[000249] In some cases, compositions comprising platelets or platelet derivatives (e.g., thrombosomes) can be rehydrated with water (e.g., sterile water for injection) over about 10 minutes at about room temperature. In general, the rehydration volume is about equal to the volume used to fill each vial of thrombosomes prior to drying. [000250] In some embodiments, the platelets or platelet derivatives (e.g., thrombosomes) prepared as disclosed herein have a storage stability that is at least about equal to that of the platelets prior to the preparation.

[000251] In some embodiments, the method further comprises cryopreserving the platelets or platelet derivatives prior to administering the platelets or platelet derivatives (e.g., with a preparation agent, e.g., a preparation agent described herein).

[000252] In some embodiments, the method further comprises drying a composition comprising platelets or platelet derivatives, (e.g., with a preparation agent e.g., a preparation agent described herein) prior to administering the platelets or platelet derivatives (e.g., thrombosomes). In some embodiments, the method may further comprise heating the composition following the drying step. In some embodiments, the method may further comprise rehydrating the composition following the freeze-drying step or the heating step.

[000253] In some embodiments, the method further comprises freeze-drying a composition comprising platelets or platelet derivatives (e.g., with a preparation agent e.g., a preparation agent described herein) prior to administering the platelets or platelet derivatives (e.g., thrombosomes) In some embodiments, the method may further comprise heating the composition following the freeze-drying step. In some embodiments, the method may further comprise rehydrating the composition following the freeze-drying step or the heating step.

[000254] In some embodiments, the method further comprises cold storing the platelets, platelet derivatives, or the thrombosomes prior to administering the platelets, platelet derivatives, or thrombosomes (e.g., with a preparation agent, e.g., a preparation agent described herein).

[000255] Storing conditions include, for example, standard room temperature storing (e.g., storing at a temperature ranging from about 20 to about 30 °C) or cold storing (e.g., storing at a temperature ranging from about 1 to about 10°C). In some embodiments, the method further comprises cry opreserving, freeze- drying, thawing, rehydrating, and combinations thereof, a composition comprising platelets or platelet derivatives (e.g., thrombosomes) (e.g., with a preparation agent e.g., a preparation agent described herein) prior to administering the platelets or platelet derivatives (e.g., thrombosomes). For example, in some embodiments, the method further comprises drying (e.g., freeze-drying) a composition comprising platelets or platelet derivatives (e.g., with a preparation agent e.g., a preparation agent described herein) (e.g., to form thrombosomes) prior to administering the platelets or platelet derivatives (e.g., thrombosomes). In some embodiments, the method may further comprise rehydrating the composition obtained from the drying step.

[000256] In some embodiments, provided herein is a method for preparing a composition comprising platelets or platelet derivatives (e.g., thrombosomes). The method can include diluting a starting material comprising platelets with an approximately equal weight (±10%) of a preparation agent (e.g., Buffer A, as provided in Example 1), concentrating the platelets to about 2250 x 10³ cells/pL (±250 x 10³) and then washed with 2-4 diavolumes (DV) (e.g., about 2 diavolumes) of the preparation agent to form a TFF- treated composition. The residual plasma percentage can be less than about 15% relative plasma (as determined by plasma protein content). Following washing, if the concentration of the cells in the TFF- treated composition is not about 2000 x 10³ cells/pL (±300 x 10³), the cells can be diluted with the preparation agent or can be concentrated to fall within this range. The method can further include lyophilizing the TFF -treated composition and subsequently treating the lyophilized composition comprising platelets or platelet derivatives (e.g., thrombosomes) at about 80 °C for about 24 hours. In some embodiments, the method can further include a pathogen reduction step, for example, before diluting the starting material.

Plurality of containers containing platelet derivative composition

[000257] The platelet derivative composition as described herein can be contained in containers/vials, which further can be packed into a plurality of containers for shipping to a customer, which can be part of a commercialization process to fulfill an order for such platelet derivative composition. The containers, in certain embodiments, are5 ml vials, 10 ml vials, 20 ml vials, 25 ml vs, 30 ml vials, 40 ml vials, 50 ml vials, 60 ml vials, 75 ml vials, 100 ml vials, 125 ml vials, 150 ml vials, 200 ml vials, or 250 ml vials. The vial(s) can be a cryovial, or a cryotube especially in illustrative embodiments where the TFF -treated composition that includes platelets is lyophilized to obtain the platelet derivative composition in the form of a powder, which further can be baked or not baked after it is lyophilized. In some embodiments, the volume of the containers in a plurality of containers (e.g. vials or tubes), which for example can be all from one lot, or from more than one lot (e.g. 2, 3, 4, 5, 6, 7, 8, 9 or 10 lots), can vary from one or more than one size between 10-100 ml. Typically, the volume of the vial/container in embodiments where the platelet derivative is a freeze-dried solid/powder, is IX the volume of, or 1.10, 1.25, 1.5, 2, 2.5, 3, 4 or 5 times the volume of a composition that was filled in the vial before lyophilization, and/or the volume in which the powder in the vials will be rehydrated, which is an illustrative embodiment. Thus, the maximum volume of such vials can be the same or more than the volume of the composition that was filled inside prior to lyophilization or the volume in which the platelet derivative composition in the form of a powder can be rehydrated. For example, in one non-limiting embodiment, a vial with a maximum capacity of 100 ml, can be used to fdl 10 ml of a TFF-treated composition that includes platelets for lyophilization. In certain embodiments, the capacity of a vial in which a TFF-treated composition that includes platelets is lyophilized, is 1-2.5 times and in other embodiments, 1-2 times, 1-3 times, 1-4 times, 1-5 times, and in certain illustrative embodiments, 1. 1 to 2 times or 1.25 to 2 times the volume of a TFF- treated composition that is lyophilized therein.

[000258] The TFF-treated platelet composition before lyophilization, or in some embodiments, the platelet derivative composition obtained after the lyophilization step, with or without post-lyophilization heat treatment (baking), can be filled into a plurality of vessels or other powder and liquid-holding containers, such as vials, in a sterile manner. In some embodiments, the containers can vary in volume from 5-100 ml, 10-90 ml, 25-75 ml, or 5-40 ml. In some embodiments, the volume of containers can be 5 ml, 10 ml, 15 ml, 20 ml, 25 ml, 30 ml, 35 ml, 40 ml, 45 ml, 50 ml, 55 ml, 60 ml, 65 ml, 70 ml, 75 ml, 80 ml, 85 ml, 90 ml, 95 ml, or 100 ml. In some embodiments, the volume of containers can be above 100 ml, for example, 125 ml, 150 ml, 175 ml, or 200 ml. The platelet derivative composition as described herein can be filled in vials of different volumes as per the commercialization requirements. A plurality (or collection) of containers having the platelet derivative composition as per any of the embodiments herein, obtained by lyophilizing the composition that includes platelets during one process (e.g. TFF or other process) for preparing a platelet derivative, can be referred to as a “batch” or a “lot”. In some embodiments, a batch/lot can have 10 -500 vials, 25-450 vials, 50-350 vials, 100-300 vials, or 150-250 vials. In some embodiments, a batch/lot can have 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 250, 300, 350, 400, 450, or 500 vials. In some embodiments, the number of vials per batch/lot can be increased to more than 500 as per the requirements, for example, 600, 700, 800, 900, or 1000 vials. In some embodiments, the number of vials can be 10-1000, 50-1000, 100-900, 200-800, 100-500, 100-400, 150-700, or 150-500 vials. The containers in a batch/lot can have a volume in the range of 5-100 ml, for example, such that a lot has several containers with the same volume or containers with different volumes. For example, 200 vials/containers in a batch/lot can have a volume of 10 ml each, 100 vials/containers in the same or a separate batch/lot can have a volume of 20 ml each, 100 vials/containers in the same or another batch/lot can have a volume of 30 ml each, or 300 vials/containers in the same or a different batch/lot can have a volume of 10 ml each. The number of containers (e.g. vials) in which a platelet derivative composition as per one of the embodiments or aspects described herein can be packed in a batch/lot can vary with manufacturing requirements, the requirements of downstream processes, for example clinical processes, and the amount of starting material comprising platelet composition. [000259] The quantity of platelet derivatives that is present in a batch/lot can vary based on the units of starting material comprising platelets that is used to produce the platelet derivatives. Certain methods provided herein, such as the TFF methods provided herein, allow more platelet units to be used to make platelet derivatives with the characteristics provided herein than prior methods. This is the result, for example, of the ability to reduce the level of certain components in a platelet composition starting material, such as HLA antibodies, HNA antibodies, and/or microparticles, to very low levels, as provided herein. Accordingly, the starting material comprising platelets, the corresponding composition (e.g. TFF- treated composition) that is lyophilized in illustrative embodiments, and the resulting platelet derivative composition powder, can vary, such that for example, in some embodiments, the starting material, the TFF-treated composition, and/or the resulting platelet derivative composition powder can include 10-500 units of platelets or platelet derivatives (e.g. 0.5 to 2.5 pm in diameter), with one unit being 3xl0^u platelets or platelet derivatives. In some embodiments, the starting platelet material, the composition to be lyophilized, and/or the platelet derivative (e.g. 0.5 to 2.5 pm in diameter) composition can include, for example, 20-500 units, 30-400 units, 40-350 units, or 50-200 units of platelets or platelet derivatives, respectively. In some embodiments, the platelet units in the starting platelet composition can be a pooled platelet product from multiple donors as described herein, or multiple batches of processed platelet compositions, such as TFF-treated compositions comprising platelets, can be pooled before lyophilization. In some embodiments, there can be 1 X 10⁹ to 1 X 10¹⁶ platelets in a starting platelet composition for processing, in a platelet composition that is lyophilized, and/or of platelet derivatives in a platelet derivative composition that is produced after lyophilization, per batch/lot. In some embodiments, the platelet-containing starting composition, the platelet composition that is lyophilized, and/or the platelet derivatives that are produced, typically after lyophilization per batch/lot can vary from 1 X 10¹⁰ to 1 X 10¹⁵, 1 X 10¹¹ to 1 X 10¹⁵, 1 X 10¹² to 1 X 10¹⁶, 1 X 10¹³ to 1 X 10¹⁵ or 1 X 10¹³ to 1 X 10¹⁴.

[000260] In certain illustrative embodiments, platelet derivative compositions that are present in a liquid, or in illustrative embodiments, a solid form such as a dried powder in the plurality of containers (e.g. vials), in illustrative embodiments of a 1 or more lots, are compositions that include platelet derivatives, wherein at least 50% of the platelet derivatives are CD 41-positive platelet derivatives, wherein less than 15%, 10%, or in further, non-limiting illustrative embodiments less than 5% of the CD 41-positive platelet derivatives are microparticles having a diameter of less than 0.5 pm, and wherein the platelet derivatives have a potency of at least 0.5, 1.0 and in further, non-limiting illustrative embodiments 1.5 thrombin generation potency units (TGPU) per 10⁶ platelet derivatives. In certain illustrative embodiments, including non-limiting examples of the illustrative embodiment in the preceding sentence, the platelet derivatives are 0.5 to 2.5 um in diameter. Such platelet derivatives and platelet derivative compositions comprising the same, can have additional characteristics disclosed herein for such derivatives and compositions.

[000261] Processes provided herein for producing platelet derivative compositions, provide better lot to lot consistency than prior processes. For example, TFF methods provided herein provide improved lot to lot variability with respect to the components of compositions that include platelet derivatives prepared therein, in illustrative embodiments, compositions that include freeze-dried platelet derivates. Such freeze-dried platelet derivatives can be one of, or the main active ingredient(s). In some embodiments, a plurality of containers provided herein comprise the platelet derivative composition from at least 2 different lots in separate containers. In some embodiments, the amount of plasma protein in the powder of any two containers chosen from different lots, differs by less than 50%, 40%, 30%, 25%, or 20%, and in illustrative embodiments less than 10%, 5%, 2%, 1%, or 0.5%. The TFF process is highly controllable and can be stopped at a certain A280 for example, from 2.0AU to 0.01 AU, or when it reaches 15% to 0.01% protein concentration in the composition that is to be lyophilized (e.g.TFF-treated composition), therefore, the plasma protein content can be very consistent not only within the containers/vials of a lot, but even between lots as well. Since different lots of platelet derivative compositions provided herein are typically prepared from platelets from different subjects or different combinations of subjects (e.g. pooled platelets from 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 40, 50, 60, 70 , 75, 80, or 100 subjects), different lots in illustrative embodiments differ in amino acid sequence of at least one (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 1-100, or 1-10) of the proteins in, on, and/or associated with platelet derivatives of the compositions therein between the lots. In illustrative embodiments, these one or more amino acid differences occur at one or more (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 1-100, or 1-10) of the site(s) of SNPs, in illustrative embodiments non-synonymous SNPs. In certain embodiments, such SNPs or non-synonymous SNPs have a minor allele frequency of less than or equal to 5%. In some embodiments, such pooled platelets are provided by processes provided herein, for example because HLA or HNA antibody levels can be reduced to very low or non-existent levels. Thus, not only can platelets be pooled from more subjects, before processing to form platelet derivatives, but those subjects can be males or females. As a result, platelet derivatives, in illustrative embodiments, FDPDs, of compositions herein, for example liquid or dried compositions, in some embodiments have different amino acid sequences for at least 1 or a plurality of FDPD proteins. Furthermore, as a result, in certain embodiments, within a lot or between lots, greater than 10%, 20%, 25%, 30%, or 40%, and in illustrative embodiments greater than 50%, 60%, 70%, 75%, 80%, 90%, or 95% of amino acids encoded by SNPs, in illustrative embodiments encoded by non- synonymous SNPs in one or more proteins that are bound to or otherwise associated with or part of a platelet derivative, are present for SNPs, for example with a minor allele frequency of greater than 5%, in

79

RECTIFIED SHEET (RULE 91 ) ISA/EP certain embodiments including in proteins that result from expression of coding sequences comprising SNPs, in illustrative embodiments non-synonymous SNPs on a mammalian X and Y chromosome.

[000262] In some embodiments, the amount of microparticles that are less than 0.5 pm in the powder of any two containers chosen from different lots, differs in amount by less than 10%, 5%, 2%, or 1%. Since, for example, a TFF process disclosed herein is very controllable, the concentration of microparticles to be obtained in the platelet derivative composition can be optimized, for example, by performing scattering intensity studies at different time points. Once the desired level is achieved, the TFF-treated composition can be lyophilized and packed in the vials with or without the baking step.

[000263] In some embodiments, the percentage by weight of platelet derivative in the powder of any two containers chosen from different lots, differs by less than 10%, 5%, 2%, or 1%. The TFF process can be optimized to achieve a pre -determined level of platelet derivatives in the TFF-treated composition. Such a TFF-treated composition when lyophilized gives a platelet composition in the form of a powder having a certain weight percentage of platelet derivatives. Since, the TFF process is controllable, in some embodiments, there can be a minimum or a negligible variation in the weight percentages of the platelet derivatives in any two containers chosen from different lots.

[000264] In some embodiments, at least one container comprises a first lot of platelet derivatives and the one or more other containers comprise a second lot of platelet derivatives. In some embodiments, plurality of containers comprises the platelet derivative composition from at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 different lots, wherein the platelet derivative composition in at least 2 of the lots have a different amino acid sequences for at least one protein of a collection of protein gene products from a corresponding collection of encoding genes. In illustrative embodiments all, of the lots have a different amino acid sequences for at least one protein of a collection of protein gene products from a corresponding collection of encoding genes. In some embodiments, the amino acid difference(s) is at one or more residues corresponding to amino acid residues encoded by a non-synonymous single nucleotide polymorphism (SNP).

[000265] As per one of the embodiments, a platelet derivative composition as described herein can be prepared from multiple donors of a single species, for example, mammals, such as for example canine, equine, porcine and in illustrative embodiments humans that are genetically different, in order to obtain a platelet derivative composition to prepare allogenic platelet derivatives, an allogenic platelet derivative product, and/or a composition comprising allogenic platelet derivatives. Such a platelet derivative composition can be filled in vials and a plurality of such vials can be packaged in containers, for example boxes for commercialization as described herein, to obtain a commercial product that is a composition comprising allogeneic platelet derivatives, in illustrative embodiments allogeneic freeze-dried platelet derivatives. The allogenic platelet derivatives as described herein, in some embodiments, can be a U.S. FDA-approved product comprising an allogenic platelet derivative composition. In some embodiments, a platelet derivative composition as described herein can be a European EMA-approved product comprising an allogenic platelet derivative composition. In some other embodiments, a platelet derivative composition as described herein can be a China FDA-approved product comprising an allogenic platelet derivative composition.

[000266] In some embodiments, platelets are pooled from a plurality of donors before they are used as starting material for a process for producing a platelet derivative as provided herein. Such platelets pooled from a plurality of donors can be also referred herein to as pooled platelets. In some embodiments, the donors are more than 5, such as more than 10, such as more than 20, such as more than 50, such as up to about 100 donors. In some embodiments, the donors are from 5 to 100, such as from 10 to 50, such as from 20 to 40, such as from 25 to 35. Pooled platelets can be used to make any of the platelet derivative compositions as described herein. The platelets can be pooled wherein the platelets are donated by mammalian (e.g. bovine, feline, porcine, canine, and in illustrative embodiments, human) subjects. In some embodiments, the gender of the subjects can be male or female. In some embodiments, the donor can vary from any number of male to any number of female subjects, for example, from a total of 100 donors, any number can be female donors, ranging from 0-100, 5-95, 10-90, 20-80, 30-70, or 40-60, and the rest can be male donors. In some other embodiments, the donor can be a non-human animal. In some embodiments, the donor can be a canine, equine, porcine, bovine, or feline subject.

[000267] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process that includes a plurality of containers each filled with a platelet derivative composition in the form of a powder, each of the plurality of containers are purged with at least one inert gas. In some embodiments, the inert gas can be argon, or nitrogen.

Platelet derivatives for treating disorders

[000268] In some embodiments, a platelet derivative composition, in illustrative embodiment a freeze- dried platelet derivative, including, but not limited to, those of any of the aspects or embodiments herein, or the platelet derivative composition prepared by any of the process described in the aspects or embodiments herein, can be administered, or delivered to a subject having an indication and thus afflicted with a disorder or disease that could benefit from delivery of such platelet derivative compositions. In some embodiments, such indication can be any one or a combination of Von Willebrand disease, immune thrombocytopenia (ITP), intracranial hemorrhage (ICH), traumatic brain injury (TBI), Hermansky Pudlak Syndrome (HPS), chemotherapy induced thrombocytopenia (CIT), Scott syndrome, Evans syndrome, hematopoietic stem cell transplantation, fetal and neonatal alloimmune thrombocytopenia, Bernard Soulier syndrome, acute myeloid leukemia, Glanzmann thrombasthenia, myelodysplastic syndrome, hemorrhagic shock, coronary thrombosis (myocardial infarction), ischemic stroke, arterial thromboembolism, Wiskott Aldrich syndrome, venous thromboembolism, MYH9 related disease, acute lymphoblastic lymphoma (ALL), acute coronary syndrome, chronic lymphocytic leukemia (CLL), acute promyelocytic leukemia, cerebral venous sinus thrombosis (CVST), liver cirrhosis, factor v deficiency (Owren Parahemophilia), thrombocytopenia absent radius syndrome, Kasabach Merritt syndrome, Gray platelet syndrome, aplastic anemia, chronic liver disease, acute radiation syndrome, Dengue hemorrhagic fever, pre-eclampsia, snakebite envenomation, HELLP syndrome, haemorrhagic cystitis, multiple myeloma, disseminated intravascular coagulation, heparin induced thrombocytopenia, pre-eclampsia, labor and delivery, hemophilia, cerebral (fatal) malaria, Alexander's disease (factor VII Deficiency), hemophilia C (Factor XI Deficiency), familial hemophagocytic lymphohistiocytosis, acute lung injury, hemolytic uremic syndrome, menorrhagia, chronic myeloid leukemia. In illustrative embodiments, a platelet derivative composition of any of the aspects or embodiments herein, or the platelet derivative composition prepared by any of the process described in the aspects or embodiments herein can be administered, or delivered to a subject afflicted by Immune thrombocytopenia. In certain illustrative embodiments, a platelet derivative composition of any of the aspects or embodiments herein, or the platelet derivative composition prepared by any of the process described in the aspects or embodiments herein can be administered, or delivered to a subject afflicted by Von Willebrand disease. In some embodiments, a method of treating of any of the aspects or embodiments herein, can include a method of treating a subject afflicted with any of the indications as described herein. In any of the methods herein wherein platelet derivatives are administered to a subject having any of the listed indications/disorders, the subject can have an anti-coagulant or antiplatelet agent in their body, such as in their blood, and can be, or have been within 1 month, 1 week, 5 days, 4 days, 3, days, 2 days, 1 day, 12 hours, 8 hours, or 4 hours, taking or administered an anti -coagulant and/or an anti-platelet agent.

[000269] In some embodiments, a platelet derivative composition of any of the aspects or embodiments herein, or the platelet derivative composition prepared by any of the process described in the aspects or embodiments can be used to treat a subject having any one or a combination of any of the indications as described herein. In certain embodiments, a platelet derivative composition as described herein can be used, for example as a medicament or in the manufacture of a kit, for treating a subject having any one or a combination of indication as disclosed herein.

[000270] In some embodiments, an indication or indications can include those type of indications which require a much higher dose of the platelet derivatives herein, or would require an unsafe dose of, or cannot be treated with, unmodified, cold stored, naturally-occurring, endogenous, autologous, allogeneic, or normal platelets, platelets having the characteristics of in-vivo platelets, or conventional platelets (e.g. platelets collected by a conventional method for collecting platelets such as, for example, a platelet-rich plasma-method, a buff coat-method, or by apheresis), but are treatable using a platelet derivative composition of any of the aspects or embodiments herein, or the platelet derivative composition prepared by any of the processes disclosed herein, in illustrative embodiments freeze-dried platelet derivatives. In some embodiments, such an indication can be an indication that is associated with defective platelet production in a subject. In some embodiments, such an indication can be an indication that is associated with a defective platelet activity in a subject. In some embodiments, such an indication can be any of the indication as described herein. In some embodiments, indications that are typically cannot be treated with conventional platelets, but are treatable with a platelet derivative composition as disclosed herein are Von Willebrand disease, immune thrombocytopenia (ITP), intracranial hemorrhage (ICH), traumatic brain injury (TBI), Hermansky Pudlak Syndrome (HPS), Chemotherapy induced thrombocytopenia (CIT), Scott syndrome, Evans syndrome, Hematopoietic Stem Cell Transplantation, Fetal and neonatal alloimmune thrombocytopenia, Bernard Soulier syndrome, Acute myeloid leukemia, or combinations thereof. In some embodiments, such an indication can be Von Willebrand disease. In some embodiments, such an indication can be Immune thrombocytopenia. In some embodiments, such an indication can be Chemotherapy induced thrombocytopenia (CIT). In some embodiments, such an indication can be fetal and neonatal alloimmune thrombocytopenia.

[000271 ] In some embodiments, an indication or indications can include those type of indications which typically, can be well-suited for treatment using a platelet derivative composition as described herein. In some embodiments, such an indication or indications can include Von Willebrand disease, immune thrombocytopenia, intracranial hemorrhage (ICH), traumatic brain injury (TBI), Hermansky Pudlak Syndrome (HPS), Scott syndrome, Evans syndrome, Bernard Soulier syndrome, Glanzmann thrombasthenia, coronary thrombosis (myocardial infarction), arterial thromboembolism, Wiskott Aldrich syndrome, venous thromboembolism, and acute coronary syndrome.

[000272] In some embodiments, platelet derivatives as described herein can have several applications in terms of treating a subject suffering with a disorder selected from the group consisting of alopecia areata, Von Willebrand Disease, hemophilia, thrombasthenia, thrombocytopenia, thrombocytopenic purpura, trauma, or a combination thereof. In some embodiments, the platelet derivatives can be used to treat clotting -related disorders. The platelet derivatives as disclosed herein can be used both as a topical application and systemic administration. In some embodiments, there is provided a method for treating a clotting -related disorder in a subject, said method comprising administering to the subject a therapeutically effective amount of the platelet derivative composition of any of the aspects or embodiments herein, or the platelet derivative composition prepared by any of the process described in the aspects or embodiments herein. In some embodiments, the clotting-related disorder is selected from the group consisting of Von Willebrand Disease, hemophilia, thrombasthenia, thrombocytopenia, thrombocytopenic purpura, trauma, or a combination thereof. In some embodiments, a platelet derivative composition is passed through a fdter of 18 pm before administering to the subject. A skilled artisan would be able to appreciate that the platelet derivative composition in the form of a powder which would be commercialized in vials would be rehydrated with an appropriate amount of a solution before administering to a subject. In some embodiments, such a rehydrated platelet derivative composition is passed through a fdter of 18 pm before administering to the subject. In some embodiments, the platelet derivative composition as disclosed herein can be used in treating a coagulopathy in a subject that has been administered or is being administered an antiplatelet agent. In some embodiments, the platelet derivative composition of any of the aspects or embodiments herein is provided for use an anti-platelet reversal agent. In some embodiments, the platelet derivative composition of any of the aspects or embodiments herein can be used in treating a coagulopathy in a subject that has been administered or is being administered an anticoagulant agent.

[000273] In some embodiments, the platelet derivatives disclosed herein can be used for healing wounds in a subject. In some embodiments, there is provided a method for healing a wound in a subject, comprising administering a therapeutically effective amount of a platelet derivative composition of any of the aspects or embodiments herein, or the platelet derivative composition prepared by any of the process described in the aspects or embodiments herein, to the subject and/or a wound of the subject.

[000274] In some embodiments, the administering can include administering topically. Administering can include administering parenterally. Administering can include administering intravenously. Administering can include administering intramuscularly. Administering can include administering intrathecally. Administering can include administering subcutaneously. Administering can include administering intraperitoneally.

[000275] Platelet derivative compositions comprising platelet derivatives as described herein can be used as a medicament for treating a subject. Further, there is also provided herein, methods of treating a subject by administering to a subject a therapeutically effective amount or dose of a platelet derivative composition comprising platelet derivatives as described herein. In some embodiments, the subject is suffering from a condition, or a disease selected from the group consisting of thrombocytopenia, hematologic malignancy, bone marrow aplasia, myeloproliferative disorders, myelodysplastic syndromes, and platelet refractoriness. In some embodiments, the subject is suffering from one or more diseases or condition as described herein. In some embodiments, a therapeutically effective dose of platelet derivatives is based on units of thrombin generation activity administered per kilogram of body weight of the subject and/or the number of platelet derivatives delivered to the subject. In some embodiments of any aspect or embodiment herein the effective dose is based on the weight of the subject. It can be contemplated by a person of skill in the art that the effective dose can be based on any criteria that suits the requirement of the medical intervention of the subject.

[000276] A person of skill in the art can contemplate the effective dose of platelet derivatives that can be required to treat a subject in need thereof. The need may differ based on the condition of the subject. The effective dosage can be categorized into a) low dosage; b) medium dosage; and c) high dosage. In some embodiments, a medicament or a method of treating a subject can have the effective dose as low, medium, or high dosage of platelet derivatives that can broadly range from 1.0 X 10⁷ on the low end of the range to 1.0 X 10¹⁰/kg, 1.0 X 10ⁿ/kg or 1.0 X 10¹²/kg of the subject on the high end of the range. [000277] In some embodiments, a platelet derivative composition as described herein can be administered or delivered to a subject, such as a subject afflicted with any one or combination of indications as described herein, and the dose of a platelet derivative composition can be in the range of 1.0 x 10⁷ to 1.0 x 10¹² particles/kg of the subject. For example, in some embodiments, a dose of a composition comprising platelets or platelet derivatives (e.g., FDPDs) can include between about or exactly 1.0 x 10⁷ on the low end of the range to 1.0 x 10¹² particles (e.g. FDPDs)/kg of a subject on the high end of the range, 1.0 x 10⁷ to 1.0 x 10¹¹ particles (e.g. FDPDs)/kg of a subject, 1.0 x 10⁷ to 1.0 x 10¹⁰ particles (e.g. FDPDs)/kg of a subject, 1.6 x 10⁷ to 1.0 x 10¹¹ particles (e.g. FDPDs)/kg of a subject, 1.6 x 10⁷ to 1.0 x 10¹⁰ particles (e.g. FDPDs/kg of subject, 1.6 x 10⁷to 5.1 x 10⁹ particles (e.g. FDPDs/kg of a subject, 1.6 x 10⁷ to 3.0 x 10⁹ particles (e.g. FDPDs)/kg of a subject, 1.6 x 10⁷ to 1.0 x 10⁹ particles (e.g. FDPDs)/kg of a subject, 1.6 x 10⁷ to 5.0 x 10⁸ particles (e.g. FDPDs)/kg of a subject, 1.6 x 10⁷ to 1.0 x 10⁸ particles (e.g. FDPDs)/kg of a subject, 1.6 xlO⁷ to 5.0 x 10⁷ particles (e.g. FDPDs)/kg of a subject, 5.0 x 10⁷ to 1.0 x 10⁸ particles (e.g. FDPDs)/kg of a subject, 1.0 x 10⁸ to 5. O x 10⁸ particles (e.g. FDPDs)/kg of a subject, 5.0 x 10⁸ to 1.0 x 10⁹ particles (e.g. FDPDs)/kg of a subject, 1.0 x 10⁹ to 5.0 x 10⁹ particles (e.g. FDPDs)/kg of a subject, 5.0 x 10⁷ to 1.0 x 10¹¹ particles (e.g. FDPDs)/kg of a subject, 5.0 x 10⁹ to 1.0 x 10¹⁰ particles (e.g. FDPDs)/kg of a subject), or 1.0 x 10¹⁰ to 1.0 x 10¹¹ or 1.0 X 10¹² particles (e.g. FDPDs)/kg of a subject on the high end of the range. In some embodiments, the dose can be in the range of 250 and 5000 TGPU per kg of the subject.

[000278] In some embodiments, a platelet derivative composition, such as that provided in any aspect or embodiment herein, can be administered or delivered to a subject afflicted with any one or combination of indications/diseases as disclosed herein, and the dose of a platelet derivative composition can be in the range of 1.0 x 10⁷ on the low end of the range to 1.0 x 10¹² particles/kg of the subject. For example, in some embodiments, a dose of a composition comprising platelets or platelet derivatives (e.g., FDPDs) can include between about or exactly 1.0 x 10⁷ on the low end of the range to 1.0 x 10¹² particles (e.g. FDPDs)/kg of a subject,, 1.0 x 10⁷ to 1.0 x 10¹¹ particles (e.g. FDPDs)/kg of a subject, 1.0 x 10⁷ to 1.0 x 10¹⁰ particles (e.g. FDPDs)/kg of a subject, 1.6 x 10⁷ to 1.0 x 10¹⁰ particles (e.g. FDPDs/kg of subject, 1.6 x 10⁷to 5.1 x 10⁹ particles (e.g. FDPDs/kg of a subject, 1.6 x 10⁷ to 3.0 x 10⁹ particles (e.g. FDPDs)/kg of a subject, 1.6 x 10⁷ to 1.0 x 10⁹ particles (e.g. FDPDs)/kg of a subject, 1.6 x 10⁷ to 5.0 x 10⁸ particles (e.g. FDPDs)/kg of a subject, 1.6 x 10⁷ to 1.0 x 10⁸ particles (e.g. FDPDs)/kg of a subject, 1.6 xlO⁷ to 5.0 x 10⁷ particles (e.g. FDPDs)/kg of a subject, 5.0 x 10⁷ to 1.0 x 10⁸ particles (e.g. FDPDs)/kg of a subject, 1.0 x 10⁸ to 5.0 x 10⁸ particles (e.g. FDPDs)/kg of a subject, 5.0 x 10⁸ to 1.0 x 10⁹ particles (e.g. FDPDs)/kg of a subject, 1.0 x 10⁹ to 5.0 x 10⁹ particles (e.g. FDPDs)/kg of a subject, or 5.0 x 10⁹ to 1.0 x 10¹⁰ particles (e.g. FDPDs)/kg of a subject). In some embodiments, a dose of a composition comprising platelets or platelet derivatives (e.g., FDPDs) can be a range of between about or exactly 1.0 x 10⁸, 5.0 x 10⁸, 1.0 x 10⁹, 3.0 x 10⁹, 4.0 x 10⁹, 5.0 x 10⁹, 1.0 x 10¹⁰, 2.5 x 10¹⁰, or 5.0 x 10¹⁰ on the low end of the range to 1.0 x 10¹² particles (e.g. FDPDs)/kg of a subject on the high end of the range. In some embodiments, and in illustrative embodiments wherein a subject has indications as described herein, a dose of a composition comprising platelets or platelet derivatives (e.g., FDPDs) can be a range of between about or exactly 3.0 x 10⁹, 4.0 x 10⁹, 5.0 x 10⁹, 1.0 x 10¹⁰, 2.5 x 10¹⁰, or 5.0 x 10¹⁰ on the low end of the range to 1.0 x 10¹² particles (e.g. FDPDs)/kg of a subject on the high end of the range. In some embodiments, and in illustrative embodiments wherein a subject has indications as described herein, a dose of a composition comprising platelets or platelet derivatives (e.g., FDPDs) can be a range of between about or exactly 3.0 x 10⁹, 4.0 x 10⁹, 5.0 x 10⁹, 1.0 x 10¹⁰, 2.5 x 10¹⁰, or 5.0 x 10¹⁰ on the low end of the range to 5.0 x 10¹¹ particles or 1.0 X 10¹² (e.g. FDPDs)/kg of a subject on the high end of the range. In some embodiments, and in illustrative embodiments wherein a subject has indications as described herein, a dose of a composition comprising platelets or platelet derivatives (e.g., FDPDs) can be a range of between about or exactly 3.0 x 10⁹, 4.0 x 10⁹, 5.0 x 10⁹, 1.0 x 10¹⁰, 2.5 x 10¹⁰, or 5.0 x 10¹⁰ on the low end of the range to 1.0 x 10¹¹ particles or 1.0 X 10¹² (e.g. FDPDs)/kg of a subject on the high end of the range. In some embodiments, and in illustrative embodiments wherein a subject has indications as described herein, a dose of a composition comprising platelets or platelet derivatives (e.g., FDPDs) can be a range of between about or exactly 3.0 x 10⁹, 4.0 x 10⁹, or 5.0 x 10⁹ on the low end of the range to 1.0 x 10¹⁰ particles (e.g. FDPDs)/kg of a subject on the high end of the range. In some embodiments, and in illustrative embodiments wherein a subject has indications as described herein, a dose of a composition comprising platelets or platelet derivatives (e.g., FDPDs) can be in a range of greater than 1.5 x 10⁹ FDPDs/kg of the subject on the low end of the range and 1.5xl0¹⁰, 1.4xlO¹⁰, 1.3xl0¹⁰, 1.2xlO¹⁰, or l. lxlO¹⁰ FDPDs/kg of the subject on the high end; or greater than 1.0 x 10¹⁰ FDPDs/kg of the subject on the low end of the range and 1.5xl0¹⁰, 1.4xlO¹⁰, 1.3xl0¹⁰, 1.2xlO¹⁰, or l. lxlO¹⁰ FDPDs/kg of the subject on the high end; or 1.1x10¹⁰ FDPDs/kg of the subject on the low end of the range and 1.5xl0¹⁰, 1.4xlO¹⁰, 1.3xl0¹⁰, or 1 ,2xlO¹⁰ FDPDs/kg of the subject on the high end; or 1. IxlO¹⁰ FDPDs/kg of the subject on the low end and less than 1.5xl0¹⁰, 1.4xlO¹⁰, 1.3xl0¹⁰, or 1.2xlO¹⁰ FDPDs/kg of the subject on the high end of the range.

[000279] In some embodiments of any aspect or embodiment herein a therapeutically effective dose or effective dose or amount of the platelet derivatives in a platelet derivative composition is in the range of

1.5 X 10⁷ to 5.0 X 10¹⁰/kg, 2.0 X 10⁷ to 1.0 X 10¹⁰/kg, 2.5 X 10⁷ to 5.0 X 10*7kg, 2.75 X 10⁷ to 3.0 X 10⁹/kg, 2.8 X 10⁷ to 4.0 X 10⁹/kg, 3.0 X 10⁷ to 4.0 X 10*7kg, 5 X 10⁷ to 4.0 X 10*7kg, 6 X 10⁷ to 3.0 X 10⁹/kg, 9 X 10⁷ to 3.0 X 10⁹/kg, 1.0 X 108 to 2.0 X 10*7kg, or 1.3 X 108 to 1.8 X 10*7kg of the subject. In some embodiments, a therapeutically effective dose or effective dose or amount of the platelet derivatives in a platelet derivative composition is in the range of 5.0 X 10⁷ to 1.0 X 10⁹/kg, 1.0 X 108 to 5.0 X 10⁸/kg,

1.2 X 10⁸ to 2.5 X 10⁸/kg, 1.6 X 10⁸ to 2.2 X 10⁸/kg, or 1.7 X 10⁸ to 2.0 X 10⁸/kg of the subject. In some embodiments, the platelet derivatives in a platelet derivative composition is 1.1 X 10⁸/kg, 1.2 X 10⁸/kg,

1.3 X 10⁸/kg, 1.4 X 10⁸/kg, 1.5 X 10⁸/kg, 1.6 X 10⁸/kg, 1.7 X 10⁸/kg, 1.8 X 10⁸/kg, 1.9 X 10⁸/kg, 2.0 X 10⁸/kg, 2.1 X 10⁸/kg, 2.2 X 10⁸/kg. 2.3 X 10⁸/kg, 2.4 X 10⁸/kg, or 2.5 X 10⁸/kg of the subject.

[000280] In some embodiments of any aspect or embodiment herein a therapeutically effective dose or effective dose or amount of the platelet derivatives in a platelet derivative composition is in the range of 5.1 X 10⁸ to 9.9 X 10⁸/kg, 5.5 X 10⁸ to 9.5 X 10⁸/kg, 5.8 X 10⁸ to 9.3 X 10⁸/kg, 6.1 X 10⁸ to 9.0 X 10⁸/kg,

6.5 X 10⁸ to 8.8 X 10⁸/kg, 6.8 X 10⁸ to 8.5 X 10⁸/kg, 7.0 X 10⁸ to 8.4 X 10⁸/kg, 7.5 X 10⁸ to 8.3 X 10⁸/kg,

7.8 X 10⁸ to 8.2 X 10⁸/kg, or 7.9 X 10⁸ to 8.1 X 10⁸/kg of the subject. In some embodiments, a therapeutically effective dose or effective dose or amount of the platelet derivatives in a platelet derivative composition is 7.5 X 10⁸/kg, 7.6 X 10⁸/kg, 7.7 X 10⁸/kg, 7.8 X 10⁸/kg, 7.9 X 10⁸/kg, 8.0 X 10⁸/kg, 8.1 X 10⁸/kg, 8.2 X 10⁸/kg, 8.3 X 10⁸/kg, 8.4 X 10⁸/kg, or 8.5 X 10⁸/kg of the subject.

[000281 ] In some embodiments of any aspect or embodiment herein a therapeutically effective dose or effective dose or amount of the platelet derivatives in a platelet derivative composition is in the range of 1.0 X 10⁹ to 1.0 X 1010/kg, 1.1 X 109 to 8.0 X 10*7kg, 1.2 X 10⁹ to 7.0 X 10*7kg, 1.2 X 10⁹ to 6.0 X 10*7kg, 1.2 X 10⁹ to 5.0 X 10*7kg, 1.3 X 10⁹ to 4.0 X 10*7kg, 1.3 X 10⁹ to 3.0 X 10*7kg, 1.3 X 10⁹ to 2.5 X 10⁹/kg, 1.4 X 10⁹ to 1.9 X 10⁹/kg, 1.50 X 10⁹ to 1.75 X 10*7kg, or 1.55 X 10⁹ to 1.70 X 10*7kg of the subject. In some embodiments, a therapeutically effective dose or effective dose or amount of the platelet derivatives in a platelet derivative composition is 1.1 X 10⁹/kg, 1.2 X 10⁹/kg, 1.3 X 10⁹/kg, 1.4 X 10⁹/kg 1.5 X 10⁹/kg, 1.55 X 10⁹/kg, 1.56 X 10*7kg, 1.57 X 10*7kg, 1.58 X 10*7kg, 1.59 X 10*7kg, 1.6 X 10*7kg, 1.61 X 10⁹/kg, 1.62 X 10⁹/kg, 1.63 X 10*7kg, 1.64 X 10*7kg, 1.65 X 10*7kg, 1.66 X 10*7kg, 1.7 X 10*7kg, 1.8 X 10⁹/kg, 1.9 X 10⁹/kg, or 2.0 X 10⁹/kg of the subject.

[000282] In some embodiments, a medicament or a method of treating a subject can have a low, medium, or high dosage of platelet derivatives that has a potency in the range of 250 to 5000 TGPU per kg of the subject.

[000283] In some embodiments of any aspect or embodiment herein a therapeutically effective dose or an effective dose or amount of the platelet derivatives is an amount that has a potency in the range of 250 to 5000 TGPU per kg, 270 to 4500 TGPU per kg, 280 to 4300 TGPU per kg, 290 to 4100 TGPU per kg, 300 to 3800 TGPU per kg, 310 to 3500 TGPU per kg, or 320 to 3000 TGPU per kg of the subject. In some embodiments, a therapeutically effective dose or effective dose or amount of the platelet derivatives is an amount that has a potency in the range of 275 to 500 TGPU per kg, 280 to 450 TGPU per kg, 290 to 400 TGPU per kg, 300 to 375 TGPU per kg, 310 to 350 TGPU per kg, or 320 to 340 TGPU per kg of the subject. In some embodiments of any aspect or embodiment herein a therapeutically effective dose or effective dose or amount of the platelet derivatives is an amount that has a potency of 270 TGPU per kg, 280 TGPU per kg, 290 TGPU per kg, 300 TGPU per kg, 310 TGPU per kg, 320 TGPU per kg, 330 TGPU per kg, 340 TGPU per kg, or 350 TGPU per kg of the subject.

[000284] In some embodiments of any aspect or embodiment herein a therapeutically effective dose or effective dose or amount of the platelet derivatives is an amount that has a potency in the range of 1001 to 2000 TGPU per kg, 1200 to 2000 TGPU per kg, 1300 to 1950 TGPU per kg, 1400 to 1900 TGPU per kg, 1500 to 1900 TGPU per kg, 1600 to 1900 TGPU per kg, 1700 to 1900 TGPU per kg, 1750 to 1875 TGPU per kg, or 1800 to 1850 TGPU per kg of the subject. In some embodiments, a therapeutically effective dose or effective dose or amount of the platelet derivatives is an amount that has a potency of 1780 TGPU per kg, 1790 TGPU per kg, 1800 TGPU per kg, 1810 TGPU per kg, 1820 TGPU per kg, 1830 TGPU per kg, 1840 TGPU per kg, or 1850 TGPU per kg of the subject.

[000285] In some embodiments of any aspect or embodiment herein a therapeutically effective dose or effective dose or amount of the platelet derivatives is an amount that has a potency in the range of 2001 to 3500 TGPU per kg, 2300 to 3300 TGPU per kg, 2500 to 3100 TGPU per kg, 2600 to 3100 TGPU per kg, 2700 to 3100 TGPU per kg, 2800 to 3100 TGPU per kg, 2850 to 3050 TGPU per kg, 2900 to 3000 TGPU per kg, or 2940 to 2990 TGPU per kg of the subject. In some embodiments, a therapeutically effective dose or effective dose or amount of the platelet derivatives is an amount that has a potency of 2910 TGPU per kg, 2920 TGPU per kg, 2930 TGPU per kg, 2940 TGPU per kg, 2950 TGPU per kg, 2960 TGPU per kg, 2970 TGPU per kg, 2980 TGPU per kg, 2990 TGPU per kg, 3000 TGPU per kg, or 3100 TGPU per kg of the subject.

[000286] In certain embodiments, any of the dose ranges provided above, and in illustrative embodiments those that include less than 1 x 10¹¹ particles/kg, or any of the ranges provided herein, for example those provided in the paragraph immediately above, can be administered more than 1 time to a subject. For example, a dose range of between 1.0 x 10⁷ particles to about 1.0 x 10¹⁰ particles, can be administered between 2 and 10 times, or between 2 and 8 times, or between 2 and 6 times, or between 3 and 8 times, or between 3 and 6 times, or between 4 and 6 times in a timeframe between within 1, 2, 3, 4, 5, or 7 days from the first dose.

[000287] In a method of treating a subject with platelet derivatives as described herein, there can be several endpoints that determine if the subject is treated. A method of treating can have one or more primary endpoints. A method can additionally have one or more secondary endpoints. In some embodiments, in a method of treatment or a composition for use as a medicament as described herein, a method or a medicament leads to cessation or decrease in bleeding at a primary bleeding site at 12 hours, 24 hours, 48 hours, 72 hours, 4 days, 5 days, 6 days, and/or 7 days after administering the platelet derivative composition. In illustrative embodiments, a method or a medicament as described herein leads to cessation or decrease in bleeding at bleeding sites other than primary bleeding site at 24 hours after administering the platelet derivative composition. In some embodiments, the primary bleeding site is based upon the most severe bleeding location of the subject within 12 hours prior to administering the platelet derivative composition. In some embodiments, the administering involves infusing a platelet derivative composition. In some embodiments, a platelet derivative composition is administered on Day 1 of the treatment. In some embodiments, the cessation or decrease is evidenced by an ordinal change in WHO bleeding score of the subject evaluated at 24 hours after administering the platelet derivative composition to the subject. In some embodiments, a method or a medicament as described herein leads to cessation or decrease in bleeding at bleeding sites other than primary bleeding site at 12 hours, 24 hours, 48 hours, 72 hours, 4 days, 5 days, 6 days, and 7 days after administering the platelet derivative composition. In some embodiments, the bleeding in a subject is a non-compressible bleeding or a non- compressible hemorrhage. A non-compressible hemorrhage is a type of hemorrhage that is inaccessible to a tourniquet or pressure dressing. In some embodiments, a method or a medicament leads to an increase in platelet count in the subject at 12 hours, 24 hours, 48 hours, 72 hours, 4 days, 5 days, 6 days, and 7 days after administering the platelet derivative composition. In some embodiments, the increase is at least 500 platelets/pl, 1000 platelets/pl, 2000 platelets/pl, 3000 platelets/pl, 4000 platelets/pl, 5000 platelets/pl, 6000 platelets/pl, 7000 platelets/pl, 8000 platelets/pl, 9000 platelets/pl, or 10000 platelets/pl in the subject. In some embodiments, the increase is in the range of 500 to 10000 platelets/pl, 1000 to 10000 platelets/pl, 2000 to 8000 platelets/pl, or 3000 to 7000 platelets/pl in the subject. In some illustrative embodiments, the increase can be at least 5000 platelets/pl.

[000288] In some embodiments, a method or a medicament leads to changes, or in other embodiments, does not lead to changes, in one or more markers of endothelial cell injury in the subject from a preadministration time through 12 hours to 35 days, 24 hours to 32 days, 24 hours to 30 days, or 48 hours to 28 days after administering the platelet derivative composition. In illustrative embodiments, a method or a medicament leads to changes, or in other embodiments, does not lead to changes, in one or more markers of endothelial cell injury in the subject from a pre-administration time through baseline to 72 hours after administering the platelet derivative composition. In some embodiments, the method or the medicament leads to changes in two or more markers, three or markers, four or more markers, five or more markers, or all of the markers selected from the group consisting of Syndecan-1, hyaluronan, thrombomodulin, vascular endothelial growth factor (VEGF), interleukin 6, and sVE cadherin. In some embodiments, the changes can be an increase or a decrease in the markers of endothelial cell injury in the subject as compared to a control.

[000289] In some embodiments, a method or a medicament leads to acceptable measures of coagulation in the subject at between 12 hours to 35 days, 24 hours to 32 days, 24 hours to 30 days, or 24 hours to 28 days after administering the platelet derivative composition. In illustrative embodiments, a method or a medicament leads to acceptable measures of coagulation in the subject at 72 hours after administering the platelet derivative composition. In some embodiments, the acceptable measure of coagulation includes one or more, two or more, three or more, four or more, five or more, or all of prothrombin time (PT), international normalized ratio (INR), fibrinogen, D-dimer, activated partial thromboplastin time (aPTT), and thromboelastography (TEG) or rotational thromboelastometry (ROTEM). In some embodiments, a method or a medicament leads to an increase or a decrease in the acceptable measure of coagulation in the subject as compared to a control.

[000290] In some embodiments, a method or a medicament leads to acceptable measures of hematology in the subject from a pre-administration time through 12 hours to 35 days, 24 hours to 32 days, 24 hours to 30 days, or 48 hours to 28 days after administering the platelet derivative composition. In some embodiments, the acceptable measures of hematology are one or more, two or more, three or more, four or more, five or more, or all selected from the group consisting of Prothrombin Fragment 1+2, thrombin generation assay (TGA), Thrombopoietin, activated Protein C, tissue plasminogen activator (TP A), and/or plasminogen activator inhibitor (PAI). In some embodiments, the acceptable measures of hematology can be an increase or a decrease in the subject as compared to a control.

[000291 ] In some embodiments, a method of treatment or a composition for use as a medicament as described herein, a method or a medicament leads to survival of the subject without WHO Grade 2A or greater bleeding during the first 3, 4, 5, 6, 7, 8, 9, or 10 days after administering of a platelet derivative composition.

[000292] In some embodiments, administering confers an improved survival at 10, 15, 20, 25, 30, 35, 40, 45, or 50 days after administering the platelet derivatives. In some embodiments, administering leads to a decrease in administration of secondary blood products, platelets, or platelet derivatives to the subject for the first 5, 6, 7, 8, 9, or 10 days after the administering of the platelet derivatives.

[000293] A person of skill in the art can contemplate treating a subject or using platelet derivatives as described herein as a medicament in several doses in a span of time for treating the subject. In some embodiments, administering of platelet derivatives as described herein is performed in a maximum of 2, 3, 4, 5, 6, 7, 8, 9, or 10 doses in a 72-hour period of treatment. Further, in some embodiments, the subject involved in the treatment or a medication process satisfies certain criteria involving one or more of: minimum age; minimum weight; total circulating platelets (TCP); confirmed diagnosis of hematologic malignancy, myeloproliferative disorder, myelodysplastic syndrome or aplasia; undergoing chemotherapy, immunotherapy, radiation therapy or hematopoietic stem cell transplantation; refractory to platelet transfusion defined as two 1-hour CCI of <5000 on consecutive transfusions of liquid stored platelets; and WHO Bleeding Score of 2 excluding cutaneous bleeding. In some embodiments, the subject has a count of total circulating platelets (TCP) between 5,000 to 100,000 platelets/pl, 10,000 to 90,000 platelets/pl, 10,000 to 80,000 platelets/pl, or 10,000 to 70,000 platelets/pl of blood at the time of administering. In some embodiments, the subject is undergoing one or more, two or more, three or more, or all of chemotherapy, immunotherapy, radiation therapy or hematopoietic stem cell transplantation at the time of administering. In some embodiments, the subject is refractory to platelet transfusion, wherein refractory is a two 1-hour CCI [corrected count increment] of <5000 on consecutive transfusions of liquid stored platelets. In some embodiments, the subject has a WHO bleeding score of 2 excluding cutaneous bleeding. In some embodiments, the subject at the time of administering has one, two or more, or all of: confirmed diagnosis of hematologic malignancy, myeloproliferative disorder, myelodysplastic syndrome, or aplasia; undergoing chemotherapy, immunotherapy, radiation therapy or hematopoietic stem cell transplantation; or refractory to platelet transfusion wherein refractory is a two 1-hour CCI of <5000 on consecutive transfusions of liquid stored platelets.

Delivery to a subject being treated with an anti-platelet or anti-coagulant agent [000294] In some aspects and embodiments, platelet derivatives provided herein can be used to treat a coagulopathy in a subject that has been administered or is being administered an antiplatelet agent or an anticoagulant agent. Accordingly, in related aspects and embodiments platelet derivatives as provided herein can be used as an anti-platelet reversal agent, or an anti-coagulant reversal agent. The antiplatelet class of drugs, which an illustrative class of antiplatelet agents, is widely used to prevent unwanted clotting episodes that lead to heart failure, stroke, and the like. In many cases, an antiplatelet drug may need to be reversed or stopped. In the case of advanced notice, as in a pre-planned surgery situation, the antiplatelet drug dose can sometimes be stopped before the surgery, preventing unwanted bleeding during surgery. In the case where an antiplatelet agent needs reversing quickly, reversal agents are typically not readily available, are expensive, or carry significant risk to the patient. In the case of need for rapid antiplatelet reversal, a platelet transfusion is typically administered, though the response to this is often only partial reversal. The caveat of this course of reversal is that the newly-infused platelets themselves are susceptible to circulating drug antiplatelet activity whereas, in some embodiments, compositions as described herein (e.g., including thrombosomes) are not. In some embodiments, compositions as described herein (e.g., including thrombosomes) are an active reversal agent. In some embodiments, the hemostatic activity of compositions as described herein (e.g., including thrombosomes) does not succumb to antiplatelet drugs. In some embodiments, an antiplatelet agent can be selected from the group consisting of aspirin, cangrelor, ticagrelor, clopidogrel, prasugrel, eptifibatide, tirofiban, abciximab, and combinations thereof.

[000295] In some embodiments of any of the methods for treating or methods of administering aspects herein, the subject is being treated or was treated with an anti -coagulant. In certain embodiments, the anticoagulant is dabigatran, argatroban, hirudin, rivaroxaban, apixaban, edoxaban, fondaparinux, warfarin, heparin, a low molecular weight heparin, a supplement, or a combination thereof. In some embodiments of any of the methods for administering or for treating aspects herein, wherein the subject is being treated with an anticoagulant, the anticoagulant is dabigatran, argatroban, hirudin, rivaroxaban, apixaban, edoxaban, fondaparinux, warfarin, heparin, low molecular weight heparins, tifacogin, Factor VIlai, SB249417, pegnivacogin (with or without anivamersen), TTP889, idraparinux, idrabiotaparinux, SR23781A, apixaban, betrixaban, lepirudin, bivalirudin, ximelagatran, phenprocoumon, acenocoumarol, indandiones, fluindione, a health and wellness supplement with anti-coagulant properties, or a combination thereof.

[000296] In some embodiments, there is provided a method of administering to a subject, or a method of treating coagulopathy in a subject, wherein the subject has been treated or is being treated with an antiplatelet agent or an anti-coagulant, the method comprising administering to the subject in need thereof an effective amount of a composition comprising platelet derivatives as described herein and an incubating agent comprising one or more salts, a buffer, optionally a cryoprotectant, and optionally an organic solvent. In some embodiments, there is provided a method of restoring normal hemostasis in a subject, the method comprising administering to the subject in need thereof an effective amount of a composition comprising platelet derivatives as described herein and an incubating agent comprising one or more salts, a buffer, optionally a cryoprotectant, and optionally an organic solvent. In some embodiments, there is provided a method of preparing a subject for surgery, the method comprising administering to the subject in need thereof an effective amount of a composition comprising platelet derivative composition as described herein and an incubating agent comprising one or more salts, a buffer, optionally a cryoprotectant, and optionally an organic solvent.

[000297] In some embodiments, the subject that has been administered or is being administered an antiplatelet agent or an anticoagulant agent in a subject having an indication and thus afflicted with a disorder or disease, that is any one or a combination of Von Willebrand disease, immune thrombocytopenia, intracranial hemorrhage (ICH), traumatic brain injury (TBI), Hermansky Pudlak Syndrome (HPS), chemotherapy induced thrombocytopenia (CIT), Scott syndrome, Evans syndrome, Hematopoietic Stem Cell Transplantation, fetal and neonatal alloimmune thrombocytopenia, Bernard Soulier syndrome, acute myeloid leukemia, Glanzmann thrombasthenia, myelodysplastic syndrome, hemorrhagic shock, coronary thrombosis (myocardial infarction), ischemic stroke, arterial thromboembolism, Wiskott Aldrich Syndrome, venous thromboembolism, MYH9 related disease, Acute Lymphoblastic Lymphoma (ALL), Acute Coronary Syndrome, Chronic Lymphocytic Leukemia (CLL), Acute Promyelocytic Leukemia, Cerebral Venous Sinus Thrombosis (CVST), Liver Cirrhosis, factor V Deficiency (Owren Parahemophilia), Thrombocytopenia absent radius syndrome, Kasabach Merritt syndrome, Gray platelet syndrome, aplastic anemia, chronic liver disease, acute radiation syndrome, Dengue hemorrhagic fever, pre-eclampsia, snakebite envenomation, HELLP syndrome, haemorrhagic cystitis, multiple myeloma, disseminated intravascular coagulation, heparin induced thrombocytopenia, pre-eclampsia, labor and delivery, hemophilia, cerebral (fatal) malaria, Alexander's Disease (Factor VII deficiency), hemophilia c (factor xi deficiency), familial hemophagocytic lymphohistiocytosis, acute lung injury, hemolytic uremic syndrome, menorrhagia, chronic myeloid leukemia.

[000298] Provided herein in one aspect is a method of treating a coagulopathy in a subject, the method including administering to the subject in need thereof an effective amount of a composition including platelets, or in illustrative embodiments platelet derivatives, and in further illustrative embodiments FDPDs, thereby treating the coagulopathy. In illustrative embodiments, the composition comprising the platelet derivatives is administered such that the bleeding potential of the subject is reduced, and in illustrative embodiments such that normal hemostasis is restored in the subject.

[000299] In one aspect, provided herein is a method of treating a coagulopathy in a subject, the method including administering to the subject in need thereof an effective amount of a composition prepared by a process including incubating platelets with an incubating agent including one or more salts, a buffer, optionally a cryoprotectant, and optionally an organic solvent, and in illustrative embodiments freeze- drying the incubated platelets, to form the composition, wherein the composition includes platelet derivatives, and in illustrative embodiments FDPDs, thereby treating the coagulopathy. In illustrative embodiments, the composition comprising the platelet derivatives is administered such that the bleeding potential of the subject is reduced, and in illustrative embodiments such that normal hemostasis is restored in the subject.

[000300] In one aspect, provided herein is a method of restoring normal hemostasis in a subject, the method including administering to the subject in need thereof an effective amount of a composition including platelets, or in illustrative embodiments platelet derivatives, and in further illustrative embodiments FDPDs, thereby treating the coagulopathy. In illustrative embodiments, the composition comprising the platelet derivatives is administered such that the bleeding potential of the subject is reduced, and in illustrative embodiments such that normal hemostasis is restored in the subject.

[000301] In one aspect, provided herein is a method of restoring normal hemostasis in a subject, the method including administering to the subject in need thereof an effective amount of a composition prepared by a process including incubating platelets with an incubating agent including one or more salts, a buffer, optionally a cryoprotectant, and optionally an organic solvent, and in illustrative embodiments freeze-drying the incubated platelets, to form the composition, wherein the composition comprises platelet derivatives, and in further illustrative embodiments FDPDs, thereby treating the coagulopathy. In illustrative embodiments, the composition comprising the platelet derivatives is administered such that the bleeding potential of the subject is reduced, and in illustrative embodiments such that normal hemostasis is restored in the subject.

[000302] In one aspect, provided herein is a method of preparing a subject for surgery, the method including administering to the subject in need thereof an effective amount of a composition including platelets, or in illustrative embodiments platelet derivatives, and in further illustrative embodiments FDPDs. Various properties of exemplary embodiments of such FDPDs are provided herein, thereby treating the coagulopathy. In illustrative embodiments, the composition comprising the platelet derivatives is administered such that the bleeding potential of the subject is reduced, and in illustrative embodiments such that normal hemostasis is restored in the subject. Implementations can include one or more of the following features. The surgery can be an emergency surgery. The surgery can be a scheduled surgery. [000303] In one aspect, provided herein is a method of preparing a subject for surgery, the method including administering to the subject in need thereof an effective amount of a composition prepared by a process including incubating platelets with an incubating agent including one or more salts, a buffer, optionally a cryoprotectant, and optionally an organic solvent, and in illustrative embodiments freeze- drying the incubated platelets, to form the composition, wherein the composition includes platelet derivatives, and in further illustrative embodiments FDPDs, thereby treating the coagulopathy. In illustrative embodiments, the composition comprising the platelet derivatives is administered such that the bleeding potential of the subject is reduced, and in illustrative embodiments such that normal hemostasis is restored in the subject. Various properties of exemplary embodiments of such FDPDs are provided herein. Implementations can include one or more of the following features. The surgery can be an emergency surgery. The surgery can be a scheduled surgery.

[000304] In one aspect, provided herein is a method of ameliorating the effects of an antiplatelet agent in a subject, the method including administering to the subject in need thereof an effective amount of a composition platelets, or in illustrative embodiments platelet derivatives, and in further illustrative embodiments FDPDs, thereby treating the coagulopathy. In illustrative embodiments, the composition comprising the platelet derivatives is administered such that the bleeding potential of the subject is reduced, and in illustrative embodiments such that normal hemostasis is restored in the subject.

[000305] In one aspect, provided herein is a method of ameliorating the effects of an antiplatelet agent in a subject, the method including administering to the subject in need thereof an effective amount of a composition prepared by a process including incubating platelets with an incubating agent including one or more salts, a buffer, optionally a cryoprotectant, and optionally an organic solvent, to form the composition, wherein the composition includes platelet derivatives, and in further illustrative embodiments FDPDs, thereby treating the coagulopathy. In illustrative embodiments, the composition comprising the platelet derivatives is administered such that the bleeding potential of the subject is reduced, and in illustrative embodiments such that normal hemostasis is restored in the subject.

[000306] In one aspect, provided herein is a method of treating a coagulopathy in a subject, or of restoring hemostasis in a subject, or of reducing bleeding potential of a subject that is being administered, or has been administered, an antiplatelet agent, the method comprising: administering to the subject in need thereof an effective amount of a composition comprising platelet derivatives, thereby treating the coagulopathy. In illustrative embodiments, the platelet derivatives are freeze-dried platelet derivatives (FDPDs). In further illustrative embodiments, the composition comprising the platelet derivatives is administered such that the bleeding potential of the subject is reduced, and in illustrative embodiments such that normal hemostasis is restored in the subject. [000307] In another aspect, provided herein is a method of treating a coagulopathy in a subject, or of restoring hemostasis in a subject, or of reducing bleeding potential of a subject, wherein the subject is being administered, or has been administered, an antiplatelet agent, the method comprising administering to the subject in need thereof an effective amount of the composition comprising FDPDs, wherein the composition comprising FDPDs comprises a population of FDPDs having a reduced propensity to aggregate such that no more than 10% of the FDPDs in the population aggregate under aggregation conditions comprising an agonist but no platelets, thereby treating the coagulopathy. In further illustrative embodiments, the composition comprising the FDPDs is administered such that the bleeding potential of the subject is reduced, and in illustrative embodiments such that normal hemostasis is restored in the subject.

[000308] In another aspect, provided herein is a method of preventing or mitigating the potential for a coagulopathy in a subject, the method comprises: (a) determining that information regarding whether the subject was administered an antiplatelet agent is unavailable; and (b) administering to the subject an effective amount of a composition comprising freeze-dried platelet derivatives (FDPDs). In some embodiments of such a method, information regarding whether the subject was administered an antiplatelet agent is unavailable for a reason comprising that the subject cannot be identified. In some embodiments of the method, information regarding whether the subject was administered an antiplatelet agent is unavailable for a reason comprising that the medical history of the subject is unavailable. In further embodiments information regarding whether the subject was administered an antiplatelet agent is unavailable for a reason comprising that the subject is in need of emergency treatment.

[000309] In another aspect, provided herein is a method of treating a coagulopathy in a subject or of reducing the bleeding potential of a subject, or of restoring hemostasis in a subject, wherein the method comprises: administering to the subject in need thereof an effective amount of a composition comprising platelet derivatives, in illustrative embodiments, FDPDs, wherein the subject before the administering the composition comprising platelet derivatives, was administered an antiplatelet agent and a second agent that decreases platelet function, thereby treating the coagulopathy. In further illustrative embodiments, the composition comprising the platelet derivatives is administered such that the bleeding potential of the subject is reduced, and in illustrative embodiments such that normal hemostasis is restored in the subject. In illustrative embodiments, before the administering of the composition comprising FDPDs the subject was in need thereof because of an increased risk of bleeding due to, or as a result of being administered the anti-platelet agent and the second agent.

[000310] In another aspect, provided herein is a composition comprising freeze-dried platelet derivatives (FDPDs) for treating a coagulopathy in a subject, wherein the treating comprises: administering to the subject in need thereof, an effective amount of the composition comprising FDPDs such that the bleeding potential, or risk of bleeding of the subject is reduced, wherein the subject was administered an antiplatelet agent and a second agent that decreases platelet function, and wherein the subject is in need thereof because of an increased potential for, or risk of bleeding due to, or as a result of being administered the antiplatelet agent and the second agent, thereby treating the coagulopathy.

[000311] In another aspect, provided herein is a composition comprising freeze-dried platelet derivatives (FDPDs) for treating a coagulopathy in a subject having an increased potential for, or risk of bleeding as a result of being administered or having been administered an anticoagulant, wherein the treating comprises: administering to the subject having the increased potential for, or risk of bleeding, an effective amount of the composition comprising FDPDs such that the bleeding potential or risk of bleeding of the subject is reduced, wherein the composition comprising FDPDs comprises a population of FDPDs having a reduced propensity to aggregate such that no more than 10% of the FDPDs in the population aggregate under aggregation conditions comprising an agonist but no platelets, thereby treating the coagulopathy.

[000312] In some embodiments of any of the method or use embodiments herein, a dose, and in illustrative embodiments an effective amount of a composition comprising platelets or platelet derivatives (e .g . , FDPDs) administered to a subj ect or patient, can be a range of between about or exactly 1.0 x 10⁸, 5.0 x 10⁸, 1.0 x 10⁹, 3.0 x 10⁹, 4.0 x 10⁹, 5.0 x 10⁹, 1.0 x 10¹⁰, or 5.0 x 10¹⁰to 1.0 x 10¹² particles (e.g. FDPDs)/kg of a subject. In some embodiments, and in illustrative embodiments wherein a subject has blood comprising two anti-platelet agents and/or has been administered dual anti-platelet therapy, a dose of a composition comprising platelets or platelet derivatives (e.g., FDPDs) can be a range of between about or exactly 3.0 x 10⁹, 4.0 x 10⁹, 5.0 x 10⁹, 1.0 x 10¹⁰, 2.5 x 10¹⁰, or 5.0 x 10¹⁰ to 5.0 x 10¹¹ particles (e.g. FDPDs)/kg of a subject. In some embodiments, and in illustrative embodiments wherein a subject has blood comprising two anti-platelet agents and/or has been administered dual anti-platelet therapy, a dose of a composition comprising platelets or platelet derivatives (e.g., FDPDs) can be a range of between about or exactly 3.0 x 10⁹, 4.0 x 10⁹, 5.0 x 10⁹, 1.0 x 10¹⁰, 2.5 x 10¹⁰, or 5.0 x 10¹⁰ to 1.0 x 10¹¹ particles (e.g. FDPDs)/kg of a subject. In some embodiments, and in illustrative embodiments wherein a subject has blood comprising two anti-platelet agents and/or has been administered dual anti-platelet therapy, a dose of a composition comprising platelets or platelet derivatives (e.g., FDPDs) can be a range of between about or exactly 3.0 x 10⁹, 4.0 x 10⁹, or 5.0 x 10⁹ to 1.0 x 10¹⁰ particles (e.g. FDPDs)/kg of a subject. In one illustrative embodiment, and in illustrative embodiments wherein a subject has blood comprising i) an anti -plate let agent and a second agent that decreases platelet function; ii) two anti-platelet agents; and/or iii) has been administered dual anti -platelet therapy, a dose or an effective amount of a composition comprising FDPDs is between 5.0 X 10¹⁰ to 1.0 X 10¹²/kg of the subject, 5.0 X 10¹⁰ to 5.0 X 10^u/kg of the subject, 5.0 X 10¹⁰ to 1.0 X 10ⁿ/kg of the subject, 5.0 X 10⁹ to 1.0 X 10^u/kg of the subject, 5.0 X 10⁹ to 5.0 X 10¹⁰/kg of the subject, or 5.0 X 10⁹ to 1.0 X 10¹⁰/kg of the subject. In some embodiments, and in illustrative embodiments wherein a subject has blood comprising two anti -platelet agents and/or has been administered dual antiplatelet therapy, a dose of a composition comprising platelets or platelet derivatives (e.g., FDPDs) can be in a range of greater than 1.5 x 10⁹ FDPDs/kg of the subject on the low end of the range and 1.5xlO¹⁰, 1.4xlO¹⁰, 1.3xlO¹⁰, 1.2xlO¹⁰, or l. lxlO¹⁰ FDPDs/kg of the subject on the high end; or greater than 1.0 x IO¹⁰ FDPDs/kg of the subject on the low end of the range and 1.5xlO¹⁰, 1.4xlO¹⁰, 1.3xlO¹⁰, 1.2xlO¹⁰, or l. lxlO¹⁰ FDPDs/kg of the subject on the high end; or l. lxlO¹⁰ FDPDs/kg of the subject on the low end of the range and 1.5xlO¹⁰, 1.4xlO¹⁰, 1.3xlO¹⁰, 1.2xlO¹⁰, or l.lxlO¹⁰ FDPDs/kg of the subject on the high end; or l. lxlO¹⁰ FDPDs/kg of the subject on the low end and less than 1.5xlO¹⁰, 1.4xlO¹⁰, 1.3xlO¹⁰, or 1.2xlO¹⁰ FDPDs/kg of the subject on the high end.

[000313] In some embodiments, for example of aspects wherein a subject was administered the antiplatelet agent and the second agent that decreases platelet function, such a method further comprises before the administering the composition comprising FDPDs, determining that the subject was administered the antiplatelet agent and the second agent that decreases platelet function. In some embodiments, the antiplatelet agent is a first antiplatelet agent and the second agent is a second antiplatelet agent. In some embodiments, the first antiplatelet agent and the second anti-platelet agent are each different antiplatelet agents selected from aspirin, cangrelor, ticagrelor, clopidogrel, prasugrel, eptifibatide, tirofiban, abciximab, terutroban, picotamide, elinogrel, ticlopidine, ibuprofen, vorapaxar, atopaxar, cilostazol, prostaglandin El, epoprostenol, dipyridamole, treprostinil sodium, and sarpogrelate. In some embodiments, the first antiplatelet agent and the second anti-platelet agent have different mechanisms of action. In some embodiments, the first antiplatelet agent and the second anti-platelet agent are each different antiplatelet agents selected from aspirin, cangrelor, ticagrelor, clopidogrel, prasugrel, eptifibatide, tirofiban, abciximab, terutroban, picotamide, elinogrel, ticlopidine, ibuprofen, vorapaxar, atopaxar, cilostazol, prostaglandin El, epoprostenol, dipyridamole, treprostinil sodium, and sarpogrelate.

[000314] In some embodiments of any of the aspects herein, before, immediately before, at the moment before, at the moment of, and/or at an initial time of, the administering of the composition comprising platelet derivatives, for example FDPDs, the subject was or is at an increased risk of bleeding due to being administered or having been administered the anti-platelet agent. Furthermore, the subject can be at an increased risk of bleeding at 7, 6, 5, 4, 3, 2, or 1 day, 12 hours, 8 hours, 4 hours, 2 hours, 1 hour or 45, 30, 15, 10, 5, 4, 3, 2, or 1 minute before the administering of the composition comprising the platelet derivatives. In some optional embodiments, this is confirmed by laboratory testing. However, in some embodiments no laboratory testing of bleeding risk or any clotting parameter is performed 7, 6, 5, 4, 3, 2, or 1 day or sooner before and/or after the administering of the composition comprising the platelet derivatives. Bleeding risk is typically decreased after administration of an effective dose of the composition comprising platelet derivatives, in illustrative embodiments FDPDs. Furthermore, the subject may remain at an increased risk of bleeding even after the administering of the composition comprising platelet derivatives (e.g. FDPDs), for example for 1, 2, 3, 4, 5, 10, 15, 20, 30, or 45 minutes, or 1, 2, 3, 4, 5, or 8 hours, or longer after the administering, depending on how long it takes for the FDPDs to decrease the risk in the subject after they are administered. Furthermore, in some embodiments, the administration of the composition comprising the platelet derivatives (e.g. FDPDs) decreases but does not completely resolve the increased risk of bleeding in the subject.

[000315] In some embodiments, for example of aspects wherein a subject was administered the antiplatelet agent and the second agent that decreases platelet function, administration of the second agent is stopped, for example before administrating the composition comprising the platelet derivatives. In other embodiments of such aspects, administration of the second agent is continued, for example after administering the composition comprising the platelet derivatives.

[000316] In certain embodiments of any of the aspects provided herein, the method further comprises before administering the composition comprising platelet derivatives, determining in a pre-administering evaluation, that the subject has an abnormal value for one or more clotting parameters. The preadministration evaluation, in illustrative embodiments, is an in vitro laboratory test.

[000317] In certain embodiments of any of the aspects provided herein, the antiplatelet agent is selected from aspirin, cangrelor, ticagrelor, clopidogrel, prasugrel, eptifibatide, tirofiban, abciximab, terutroban, picotamide, elinogrel, ticlopidine, ibuprofen, vorapaxar, atopaxar, cilostazol, prostaglandin El, epoprostenol, dipyridamole, treprostinil sodium, and sarpogrelate. In other embodiments, the antiplatelet agent is selected from cangrelor, ticagrelor, abciximab, terutroban, picotamide, elinogrel, ibuprofen, vorapaxar, atopaxar, cilostazol, prostaglandin El, epoprostenol, dipyridamole, treprostinil sodium, and sarpogrelate.

Platelet derivatives comprising an imaging agent

[000318] In some embodiments, provided herein is a platelet derivative composition , wherein the platelet derivatives can include an imaging agent. In some embodiments, platelets can include/be loaded with an imaging agent, for example before being dried or after being dried. In some embodiments, platelet derivatives that include an imaging agent, such as imaging agent-loaded platelet derivatives can retain the ability or properties of platelet derivatives that are not loaded with imaging agents. Loading of platelet derivatives with an agent typically facilitates imaging of the platelet derivatives in vivo. Thus, a step of detecting an imaging agent, for example an MRI agent, in a subject can be included in any method herein that includes administering or otherwise delivering platelet derivatives to the subject. The imaging agent that can be used to load the platelet derivatives as described herein can include a radioactive metal ion, a paramagnetic metal ion, a gamma-emitting radioactive halogen, a positron-emitting radioactive non- metal, a hyperpolarized NMR-active nucleus, a reporter suitable for in vivo optical imaging, or a betaemitter suitable for intravascular detection. For example, a radioactive metal ion can include, but is not limited to, positron emitters such as ⁵⁴Cu, ⁴⁸V, ⁵²Fe, ⁵⁵Co, ⁹⁴Tc or ⁶⁸Ga; or gamma-emitters such as ¹⁷¹Tc, ^U1ln, ¹¹³In, or ⁶⁷Ga. For example, a paramagnetic metal ion can include, but is not limited to Gd(III), a Mn(II), a Cu(II), a Cr(III), a Fe(III) , a Co(II), a Er(II), a Ni(II), a Eu(III) or a Dy(III), an element comprising an Fe element, a neodymium iron oxide (NdFeO3) or a dysprosium iron oxide (DyFeO3). For example, a paramagnetic metal ion can be chelated to a polypeptide or a monocrystalline nanoparticle. For example, a gamma-emitting radioactive halogen can include, but is not limited to 1231, ¹³ T or ⁷⁷Br. For example, a positron-emitting radioactive non-metal can include, but is not limited to ⁿC, ¹³N, ¹⁵O, ¹⁷F, ⁷⁵Br, ⁷⁶Br or ¹²⁴I. For example, a hyperpolarized NMR-active nucleus can include, but is not limited to ¹³C, ¹⁵N, ¹⁹F, ²⁹Si and ³¹P. For example, a reporter suitable for in vivo optical imaging can include, but is not limited to any moiety capable of detection either directly or indirectly in an optical imaging procedure. For example, the reporter suitable for in vivo optical imaging can be a light scatterer (e.g., a colored or uncolored particle), a light absorber or a light emitter. For example, the reporter can be any reporter that interacts with light in the electromagnetic spectrum with wavelengths from the ultraviolet to the near infrared. For example, organic chromophoric and fluorophoric reporters include groups having an extensive delocalized electron system, e.g. cyanines, merocyanines, indocyanines, phthalocyanines, naphthalocyanines, triphenylmethines, porphyrins, pyrilium dyes, thiapyrilium dyes, squarylium dyes, croconium dyes, azulenium dyes, indoanilines, benzophenoxazinium dyes, benzothiaphenothiazinium dyes, anthraquinones, napthoquinones, indathrenes, phthaloylacridones, trisphenoquinones, azo dyes, intramolecular and intermolecular charge-transfer dyes and dye complexes, tropones, tetrazines, b/s(dithiolene) complexes, bis(benzene-dithiolate) complexes, iodoaniline dyes, b/stS.O-dithiolene) complexes. For example, the reporter can be, but is not limited to a fluorescent, a bioluminescent, or chemiluminescent polypeptide. For example, a fluorescent or chemiluminescent polypeptide is a green florescent protein (GFP), a modified GFP to have different absorption/emission properties, a luciferase, an aequorin, an obelin, a mnemiopsin, a berovin, or a phenanthridinium ester. For example, a reporter can be, but is not limited to rare earth metals (e.g., europium, samarium, terbium, or dysprosium), or fluorescent nanocrystals (e.g., quantum dots). For example, a reporter may be a chromophore that can include, but is not limited to fluorescein, sulforhodamine 101 (Texas Red), rhodamine B, rhodamine 6G, rhodamine 19, indocyanine green, Cy2, Cy3, Cy3.5, Cy5, Cy5.5, Cy7, Marina Blue, Pacific Blue, Oregon Green 88, Oregon Green 514, tetramethylrhodamine, and Alexa Fluor 350, Alexa Fluor 430, Alexa Fluor 532, Alexa Fluor 546, Alexa Fluor 555, Alexa Fluor 568, Alexa Fluor 594, Alexa Fluor 633, Alexa Fluor 647, Alexa Fluor 660, Alexa Fluor 680, Alexa Fluor 700, and Alexa Fluor 750. For example, a beta-emiter can include, but is not limited to radio metals ⁶⁷ Cu, ⁸⁹Sr, ⁹⁰Y, ¹⁵³Sm, ¹⁸⁵Re, ¹⁸⁸Re or ¹⁹²Ir, and non-metals ³²P, ³³P, ³⁸S, ³⁸C1, ³⁹C1, ⁸²Br and ⁸³Br. In some embodiments, an MRI agent loaded into platelets can be associated with gold or other equivalent metal particles (such as nanoparticles). For example, a metal particle system can include, but is not limited to gold nanoparticles (e.g., Nanogold™).

[000319] In some embodiments, an MRI agent loaded into platelets that is modified with an imaging agent is imaged using an imaging unit. The imaging unit can be configured to image the MRI agent loaded platelets in vivo based on an expected property (e.g., optical property from the imaging agent) to be characterized. For example, imaging techniques (in vivo imaging using an imaging unit) that can be used, but are not limited to are: computer assisted tomography (CAT), magnetic resonance spectroscopy (MRS), magnetic resonance imaging (MRI), positron emission tomography (PET), single-photon emission computed tomography (SPECT), or bioluminescence imaging (BLI). Chen, Z., et. al., Advance of Molecular Imaging Technology and Targeted Imaging Agent in Imaging and Therapy, Biomed Res Int., 819324, doi: 10.1155/2014/819324 (2014) have described various imaging techniques and which is incorporated by reference herein in its entirety. In some embodiments, an imaging agent is an MRI agent. In other embodiments, the MRI agent can be gadolinium -based compounds. In some embodiments, platelet derivatives that include an MRI agent, such as, MRI agent-loaded platelet derivatives can retain the ability or properties of platelet derivatives that are not loaded with MRI agents.

[000320] In some embodiments, an imaging agent as provided herein is loaded on platelets or platelet derivatives using a cell penetrating peptide (CPP). In some embodiments, an imaging agent can be conjugated to a CPP and further can be incubated with platelets or platelet derivatives to form imaging agent-loaded platelets or platelet derivatives. In some embodiments, an imaging agent can be an MRI agent to form MRI agent-loaded platelets or platelet derivatives. In some embodiments, a CPP can be any of the CPP well known in the art that can cross the cytoplasmic membrane efficiently. In some embodiments, CPP can be any peptide having 10 to 30 amino acids and are capable of crossing the cytoplasmic membrane. In some embodiments, CPP can be any of the peptides that are described in Kersemans et al 2008 (Kersemans, Veerle et al. “Cell penetrating peptides for in vivo molecular imaging applications.” Current pharmaceutical design vol. 14,24 (2008): 2415-47.). In some embodiments, CPP can be a protein-derived CPP, a synthetic CPP, or a mixed CPP. In some embodiments, a protein-derived CPP are derived from naturally occurring protein such as, but not limiting to, TAT protein, and penetratin. In some embodiments, a synthetic CPP such as, but not limiting to polyarginines can be a CPP that is developed by known techniques, such as, phage display method. In some embodiments, a mixed CPP can be a CPP which are a combination of naturally occurring (protein derived) CPP, and synthetic CPP, such as transportan CPP, a combination of the N-terminal fragment of the neuropeptide gelanin and the membrane -interacting wasp venom peptide, mastoparan. In some embodiments, a protein-derived CPPs is selected from the group consisting of penetratin, TAT peptide (49-57 amino acids), TAT peptide (48-60 amino acids), calcitonin-derived CPP, nuclear localization sequences, new polybasic CPPs, N-terminal repetitive domain of maize gamma-zein, peptides from gp41 fusion sequence, preS2-TLM, signalsequence hydrophobic region (SSHR), pVEC, Vpr, VP22, Human integrin b3 signal sequence, gp41 fusion sequence, Caiman crocodylus Ig(v) light chain, hCT derived peptide, Kaposi FGF signal sequences, CPP from pestivirus envelope glycoprotein, CPP derived from the prion protein, Yeast PRP6 (129-144), Phi21 N (12-29), Delta N (1-22), FHV coat (35-49), BMV Gag (7-25), HTLV-II Rex (4-16), HIV-1 Rev (9-20), RSG-1.2, Lambda-N (48-62), SV40 NLS, Bipartite, Nucleoplasmin (155-170), NLS, Herpesvirus, 8 k8 protein (124-135), Buforin-II (20-36), Magainin, PDX-l-PTD, crotamine, plsl, SynBl, Fushi-tarazu (254-313), and Engrailed (454-513). In certain illustrative embodiments, a protein-derived CPP is penetratin. In certain illustrative embodiments, a protein-derived CPP is TAT peptide (49-57 amino acids). In certain illustrative embodiments, a protein-derived CPP is TAT peptide (48-60 amino acids). In certain illustrative embodiments, a protein-derived CPP can be any peptide described in the publication Kersemans et al 2008.

[000321] In some embodiments, a synthetic and/or mixed CPP is selected from the group consisting of transportan, polyarginine CPPs, poly-d-arginine, KLAL peptide/model amphipathic peptide (MAP), KALA model amphipathic peptide, modeled Tat peptide, Loligomer, b-sheet-forming peptide, retro- inverso forms of established CPPs, W/R penetratin, MPG, Pep-1, Signal-sequence-based peptides (I), Signal-sequence-based peptides (II), Carbamate 9, PTD-4, PTD-5, RSV-A9, CTP-512, and U2AF. In certain illustrative embodiments, a synthetic and/or mixed CPP can be any peptide described in the publication Kersemans et al 2008.

Exemplary Embodiments

[000322] Provided in this Exemplary Embodiments section are non-limiting exemplary aspects and embodiments provided herein and further discussed throughout this specification. For the sake of brevity and convenience, all of the aspects and embodiments disclosed herein, and all of the possible combinations of the disclosed aspects and embodiments are not listed in this section. Additional embodiments and aspects are provided in other sections herein. Furthermore, it will be understood that embodiments are provided that are specific embodiments for many aspects and that can be combined with any other embodiment, for example as discussed in this entire disclosure. It is intended in view of the full disclosure herein, that any individual embodiment recited below or in this full disclosure can be combined with any aspect recited below or in this full disclosure where it is an additional element that can be added to an aspect or because it is a narrower element for an element already present in an aspect. Such combinations are sometimes provided as non-limiting exemplary combinations and/or are discussed more specifically in other sections of this detailed description.

[000323] In one aspect, provided herein is a composition comprising platelets or platelet derivatives and an aqueous medium, wherein the aqueous medium has a protein concentration less than or equal to 50% of the protein concentration of donor apheresis plasma.

[000324] In one aspect, provided herein is a platelet derivative composition in the form of a powder, comprising a population of platelet derivatives having a reduced propensity to aggregate, such that no more than 25%, 10%, 5%, 4%, 3%, or in illustrative embodiments, no more than 2%, of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets, and wherein the platelet derivatives are capable of generating thrombin, and in certain embodiments have a potency of at least 0.5, 1.0, and in non-limiting illustrative embodiments 1.5 thrombin generation potency units (TGPU) per 10⁶ platelet derivatives.

[000325] In one aspect, provided herein is a platelet derivative composition in the form of a powder, comprising a population of platelet derivatives having a reduced propensity to aggregate, wherein no more than 25%, 10%, 5%, 4%, 3%, or in illustrative embodiments, no more than 2%no more than 25%, 10%, 5%, 4%, 3%, or in illustrative embodiments, no more than 2%, of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets; and having one or more, two or more, or all of the following characteristics of a super-activated platelet selected from: a. the presence of thrombospondin (TSP) on their surface at a level that is greater than on the surface of resting platelets; b. the presence of von Willebrand factor (vWF) on their surface at a level that is greater than on the surface of resting platelets; c. an inability to increase expression of a platelet activation marker in the presence of an agonist as compared to the expression of the platelet activation marker in the absence of an agonist.

[000326] In one aspect, provided herein is a platelet derivative composition in the form of a powder, comprising platelet derivatives, wherein less than 15%, and in certain non -limiting illustrative embodiments less than 5% of the CD 41-positive platelet derivatives are microparticles, in non-limiting illustrative embodiments having a diameter of less than 1 pm, and in certain non-limiting illustrative embodiments less than 0.5 pm, and wherein the platelet derivatives are capable of generating thrombin, such that, for example, the platelet derivatives have a potency of at least 0.5, 1.0, or in non-limiting illustrative embodiments 1.5 thrombin generation potency units (TGPU) per 10⁶ platelet derivatives. [000327] In one aspect, provided herein is a platelet derivative composition in the form of a powder, comprising a population of platelet derivatives comprising CD 41 -positive platelet derivatives, wherein the population comprises platelet derivatives having a reduced propensity to aggregate such that no more than 25%, 10%, 5%, 4%, 3%, or in illustrative embodiments, no more than 2%no more than 25%, 10%, 5%, 4%, 3%, or in illustrative embodiments, no more than 2%, of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets, wherein the platelet derivatives have an inability to increase expression of a platelet activation marker in the presence of an agonist as compared to the expression of the platelet activation marker in the absence of the agonist, wherein the platelet derivatives are capable of generating thrombin, such that, for example, in illustrative embodiments the platelet derivatives are capable of generating thrombin, such that, for example, the platelet derivatives have a potency of at least 0.5, 1.0, or in non-limiting illustrative embodiments 1.5 thrombin generation potency units (TGPU) per 10⁶ platelet derivatives; and wherein less than 15%, and in certain non-limiting illustrative embodiments less than 5% of the CD 41-positive platelet derivatives are microparticles having a diameter of less than 1 pm, and in certain non-limiting illustrative embodiments less than 0.5 pm.

[000328] In one aspect, provided herein is a platelet derivative composition in the form of a powder, comprising a population of platelet derivatives having a reduced propensity to aggregate, such that no more than 25%, 10%, 5%, 4%, 3%, or in illustrative embodiments, no more than 2%no more than 25%, 10%, 5%, 4%, 3%, or in illustrative embodiments, no more than 2%, of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets, and further having one or both of: the presence of thrombospondin (TSP) on their surface at a level that is greater than on the surface of resting platelets; and the presence of von Willebrand factor (vWF) on their surface at a level that is greater than on the surface of resting platelets.

[000329] In one aspect, provided herein is a platelet derivative composition in the form of a powder, comprising a population of platelet derivatives comprising CD41 -positive platelet derivatives, wherein less thanl5%, and in certain non-limiting illustrative embodiments less than 5% of the CD41-positive platelet derivatives are microparticles having a diameter of less than 1 pm, and in certain non-limiting illustrative embodiments less than 0.5 pm, and comprising platelet derivatives having one or more of, two or more of, three or more of, and in illustrative embodiments all of the following: a reduced propensity to aggregate, in certain embodiments such that no more than 25%, 10%, 5%, 4%, 3%, and in illustrative embodiments no more than 2% of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets; an inability to increase expression of a platelet activation marker in the presence of an agonist as compared to the expression of the platelet activation marker in the absence of the agonist; the presence of thrombospondin (TSP) on their surface at a level that is greater than on the surface of resting platelets; the presence of von Willebrand factor (vWF) on their surface at a level that is greater than on the surface of resting platelets; and are capable of generating thrombin, such that, for example, in illustrative embodiments the platelet derivatives are capable of generating thrombin, such that, for example, the platelet derivatives have a potency of at least 0.5, 1.0, or in non-limiting illustrative embodiments 1.5 thrombin generation potency units (TGPU) per 10⁶ platelet derivatives.

[000330] In one aspect, provided herein is a platelet derivative composition in the form of a powder, comprising trehalose in the range of 20-35% by weight, polysucrose in the range of 45-60% by weight, and platelet derivatives in the range of 0.5-20% by weight, wherein the platelet derivatives to microparticles have a numerical ratio of at least 95: 1 in the platelet derivative composition, and wherein the platelet derivatives are capable of generating thrombin, such that, for example, in illustrative embodiments the platelet derivatives are capable of generating thrombin, such that, for example, the platelet derivatives have a potency of at least 0.5, 1.0, or in non-limiting illustrative embodiments 1.5 thrombin generation potency units (TGPU) per 10⁶ platelet derivatives.

[000331] In one aspect, provided herein is a platelet derivative composition in the form of a powder, comprising trehalose in the range of 20-35% by weight, polysucrose in the range of 45-60% by weight, and platelet derivatives in the range of 0.5-20% by weight, wherein the platelet derivative composition comprises a population of platelet derivatives having a reduced propensity to aggregate such that no more than 25%, 10%, 5%, 4%, 3%, or in illustrative embodiments, no more than 2%, of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets, and further having one or both of: the presence of thrombospondin (TSP) on their surface at a level that is greater than on the surface of resting platelets; and the presence of von Willebrand factor (vWF) on their surface at a level that is greater than on the surface of resting platelets.

[000332] In one aspect, provided herein is a plurality of containers each containing a platelet derivative composition in the form of a powder, wherein the platelet derivative composition in each container comprises a population of platelet derivatives having a reduced propensity to aggregate such that no more than 25%, 10%, 5%, 4%, 3%, or in illustrative embodiments, no more than 2% of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets, wherein the platelet derivative compositions in each container are capable of generating thrombin, such that, for example, in illustrative embodiments the platelet derivatives are capable of generating thrombin, such that, for example, the platelet derivatives have a potency of at least 0.5, 1.0, or in non-limiting illustrative embodiments 1.5 thrombin generation potency units (TGPU) per 10⁶ platelet derivatives, wherein the platelet derivatives have an inability to increase expression of a platelet activation marker in the presence of an agonist as compared to the expression of the platelet activation marker in the absence of the agonist, wherein the plurality of containers comprise the platelet derivative composition from at least 2 different lots in separate containers, and wherein one or more of: the amount of plasma protein in the powder of any two containers chosen from different lots, differs by less than 10%, 5%, 2%, or 1%, and the amount of microparticles that are less than 1 pm, and in certain non-limiting illustrative embodiments less than 0.5 pm in the powder of any two containers chosen from different lots, differs by less than 10%, 5%, 2%, or 1%.

[000333] In one aspect, provided herein is a plurality of containers each filled with a platelet derivative composition in the form of a powder, wherein the platelet derivative composition comprises trehalose in the range of 20-35% by weight; polysucrose in the range of 45-60% by weight; and platelet derivatives in the range of 0.5-20% by weight, wherein the platelet derivatives are capable of generating thrombin, such that, for example, in illustrative embodiments the platelet derivatives are capable of generating thrombin, such that, for example, the platelet derivatives have a potency of at least 0.5, 1.0, or in non-limiting illustrative embodiments 1.5 thrombin generation potency units (TGPU) per 10⁶ platelet derivatives, and a population of platelet derivatives comprising CD41 -positive platelet derivatives, wherein less than 15%, and in certain non-limiting illustrative embodiments less than 5% of the CD41-positive platelet derivatives are microparticles having a diameter of less than 1 pm, and in certain non-limiting illustrative embodiments less than 0.5 pm.

[000334] In one aspect, provided herein is a process for preparing a composition comprising platelets or platelet derivatives and an aqueous medium, the process comprising: tangential flow fdtration (TFF) of a starting material comprising platelets, a diluted starting material comprising platelets, a concentrated platelet composition, or a combination thereof, thereby preparing a composition comprising platelets or platelet derivatives and aqueous medium, wherein the aqueous medium has a protein concentration less than or equal to 50% of the protein concentration of donor apheresis plasma.

[000335] In one aspect, provided herein is a process for preparing freeze-dried platelets, comprising: a) preparing a composition comprising platelets and an aqueous medium using the process comprising: tangential flow fdtration (TFF) of a starting material comprising platelets, a diluted starting material comprising platelets, a concentrated platelet composition, or a combination thereof, thereby preparing a composition comprising platelets or platelet derivatives and aqueous medium, wherein the aqueous medium has a protein concentration less than or equal to 50% of the protein concentration of donor apheresis plasma; and b) freeze-drying the composition comprising platelets and the aqueous medium.

[000336] In one aspect, provided herein is a process for preparing a composition comprising platelets or platelet derivatives and an aqueous medium, the process comprising: diluting a starting material comprising platelets to form a diluted starting material; concentrating the diluted starting material such that the platelets have a concentration of about 2250 x 10³ cells/pL (±250 x 10³) to form a concentrated platelet composition; and washing the concentrated platelet composition with at least 2 diavolumes (DV) of a preparation agent to form a TFF-treated composition.

[000337] In one aspect, provided herein is a process for preparing a platelet derivative composition, comprising performing tangential flow fdtration (TFF) of a platelet composition with a preparation agent, in a preparation agent, or in a solution that optionally can have components of the preparation agent or can be a different solution, wherein the TFF is performed to at least partially exchange the solution with the preparation agent having a pH in the range of 5.5 to 8.0 and comprising 0.4 to 35% trehalose and 2% to 8% polysucrose, wherein said TFF is performed using a 0.3 to 1 micron fdter, to at least partially or fully exchange the platelets into the preparation agent, thereby preparing a TFF-treated composition comprising 100 x 10³ to 20,000 x 10³ platelets/pl, in certain illustrative embodiments between 10,000 x 10³ to 20,000 x 10³ platelets/pl, in an aqueous medium having less than or equal to 15% plasma protein, and having less than 15%, and in certain non-limiting illustrative embodiments less than 5.0% microparticles by scattering intensity having a diameter of less than 1 pm, and in certain non-limiting illustrative embodiments less than 0.5 pm; freeze drying the TFF-treated composition comprising platelets in the aqueous medium to form a freeze-dried composition comprising platelet derivatives; and heating the freeze-dried composition at a temperature in the range of 60°C to 90°C for at least 1 hour to not more than 36 hours to thermally treat the platelet derivatives in the freeze-dried composition to form the platelet derivative composition, wherein the platelet derivatives in the platelet derivative composition are capable of generating thrombin, such that, for example, in illustrative embodiments the platelet derivatives are capable of generating thrombin, such that, for example, the platelet derivatives have a potency of at least 0.5, 1.0, or in non-limiting illustrative embodiments 1.5 thrombin generation potency units (TGPU) per 10⁶ platelet derivatives, and a reduced propensity to aggregate, wherein no more than 25%, 10%, 5%, 4%, 3%, or in illustrative embodiments, no more than 2%, of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets. The platelets can be diluted 1:0.5, 1: 1, 1:2, 1:5, or 1: 10 in a solution or in the preparation agent before performing the TFF. [000338] In one aspect, provided herein is a process for preparing a platelet derivative composition, comprising performing tangential flow fdtration (TFF) of a platelet composition with a preparation agent, in a preparation agent, or in a solution that optionally can have components of the preparation agent or can be a different solution, wherein the TFF is performed to at least partially exchange the solution with the preparation agent having a pH in the range of 5.5 to 8.0 and comprising 0.4 to 35% trehalose and 2% to 8% polysucrose, wherein the TFF is performed using a 0.3 to 1 micron fdter, to at least partially or fully exchange the platelets into the preparation agent, thereby preparing a TFF-treated composition comprising 100 x 10³ to 20,000 x 10³ platelets/pl, in certain illustrative embodiments between 10,000 x 10³ to 20,000 x 10³ platelets/pl, in an aqueous medium having less than or equal to 15% plasma protein, and having less than 15%, and in certain non-limiting illustrative embodiments less than 5.0% microparticles by scattering intensity having a diameter of less than 1 pm, and in certain non-limiting illustrative embodiments less than 0.5 pm, freeze drying the TFF-treated composition comprising platelets in the aqueous medium to form a freeze-dried composition comprising platelet derivatives; and heating the freeze-dried composition at a temperature in the range of 60°C to 90°C for at least 1 hour to not more than 36 hours to thermally treat the platelet derivatives in the freeze-dried platelet composition to form the platelet derivative composition, wherein the platelet derivative composition is: a) negative for HLA Class I antibodies based on a regulatory agency approved test for HLA Class I antibodies; b) negative for HLA Class II antibodies based on a regulatory agency approved test for HLA Class II antibodies; and c) negative for HNA antibodies based on a regulatory agency approved test for HNA antibodies. The platelets can be diluted 1:0.5, 1: 1, 1:2, 1:5, or 1: 10 in a solution or in the preparation agent before performing the TFF.

[000339] In one aspect, provided herein is a process for preparing a platelet derivative composition, comprising performing tangential flow fdtration (TFF) of a platelet composition with a preparation agent, in a preparation agent, or in a solution that optionally can have components of the preparation agent or can be a different solution, wherein the TFF is performed to at least partially exchange the solution with the preparation agent having a pH in the range of 5.5 to 8.0 and comprising 0.4 to 35% trehalose and 2% to 8% polysucrose, wherein said TFF is performed using a 0.3 to 1 micron fdter, to at least partially or fully exchange the platelets into the preparation agent, thereby preparing a TFF-treated composition comprising 100 x 10³ to 20,000 x 10³ platelets/pl, in certain illustrative embodiments between 10,000 x 10³ to 20,000 x 10³ platelets/pl in an aqueous medium having less than or equal to 15% plasma protein, and having less than 15%, and in certain non-limiting illustrative embodiments less than 5.0% microparticles by scattering intensity having a diameter of less than 1 pm, and in certain non-limiting illustrative embodiments less than 0.5 pm; freeze drying the TFF-treated composition comprising platelets in the aqueous medium to form a freeze-dried composition comprising platelet derivatives; and heating the freeze-dried composition at a temperature in the range of 60°C to 90°C for at least 1 hour to not more than 36 hours to thermally treat the platelet derivatives in the freeze-dried composition to form the platelet derivative composition, wherein the platelet derivative composition comprising a population of platelet derivatives having a reduced propensity to aggregate, such that no more than 25%, 10%, 5%, 4%, 3%, or in illustrative embodiments, no more than 2%, of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets and having one or both of: the presence of thrombospondin (TSP) on their surface at a level that is greater than on the surface of resting platelets; and the presence of von Willebrand factor (vWF) on their surface at a level that is greater than on the surface of resting platelets. The platelets can be diluted 1:0.5, 1: 1, 1:2, 1:5, or 1 : 10 in a solution or in the preparation agent before performing the TFF.

[000340] In one aspect, provided herein is a process for preparing a process for preparing a platelet derivative composition, comprising performing tangential flow fdtration (TFF) of a platelet composition with a preparation agent, in a preparation agent, or in a solution that optionally can have components of the preparation agent or can be a different solution, wherein the TFF is performed to at least partially exchange the solution with the preparation agent having a pH in the range of 5.5 to 8.0 and comprising 0.4 to 35% trehalose and 2% to 8% polysucrose, wherein said TFF is performed using a 0.3 to 1 micron fdter, to at least partially or fully exchange the platelets into the preparation agent, thereby preparing a TFF-treated composition comprising 100 x 10³ to 20,000 x 10³ platelets/pl, in certain illustrative embodiments between 10,000 x 10³ to 20,000 x 10³ platelets/pl in an aqueous medium having less than or equal to 15% plasma protein, and having less than 15%, and in certain non-limiting illustrative embodiments less than 5.0% microparticles by scattering intensity having a diameter of less than 1 pm, and in certain non-limiting illustrative embodiments less than 0.5 pm; freeze drying the TFF-treated composition comprising platelets in the aqueous medium to form a freeze-dried composition comprising platelet derivatives; and heating the freeze-dried composition at a temperature in the range of 60°C to 90°C for at least 1 hour to not more than 36 hours to thermally treat the platelet derivatives in the freeze- dried composition to form the platelet derivative composition, wherein the platelet derivatives in the platelet derivative composition display one or more of, two or more of, three or more of, four or more of, or all of the following properties: a reduced propensity to aggregate, wherein no more than 25%, 10%, 5%, 4%, 3%, or in illustrative embodiments, no more than 2%, of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets; an inability to increase expression of a platelet activation marker in the presence of an agonist as compared to the expression of the platelet activation marker in the absence of the agonist; the presence of thrombospondin (TSP) on their surface at a level that is greater than on the surface of resting platelets; the presence of von Willebrand factor (vWF) on their surface at a level that is greater than on the surface of resting platelets; and are capable of generating thrombin, such that in illustrative embodiments, the platelet derivatives are capable of generating thrombin, such that, for example, the platelet derivatives have a potency of at least 0.5, 1.0, or in non-limiting illustrative embodiments 1.5 thrombin generation potency units (TGPU) per 10⁶ platelet derivatives. The platelets can be diluted 1:0.5, 1: 1, 1:2, 1:5, or 1: 10 in a solution or in the preparation agent before performing the TFF.

[000341] In one aspect, provided herein is a method for treating a subject, said method comprising administering to the subject, a therapeutically effective amount of platelet derivatives in a platelet derivative composition of any aspect or embodiment herein or the platelet derivative composition prepared by a process of any method of preparing or making provided herein.

[000342] In one aspect, provided herein is a platelet derivative composition comprising platelet derivatives of any aspect provided herein, or a platelet derivative composition prepared by the process of any method for preparing or making provided herein, for use as a medicament in treating a subject.

[000343] In one aspect, provided herein is a platelet derivative composition comprising platelet derivatives of any aspect provided herein, or a platelet derivative composition prepared by the process of any method for preparing or making provided herein, wherein the platelet derivatives comprise an imaging agent.

[000344] In one aspect, provided herein is a method of delivering an imaging agent to a subject, comprising: (a) rehydrating platelet derivative composition comprising platelet derivatives of any aspect provided herein, or a platelet derivative composition prepared by the process of any method for preparing or making provided herein to form rehydrated platelet derivative composition; (b) contacting the rehydrated platelet derivative composition with an imaging agent, to form imaging agent loaded-platelet derivatives; and (c) administrating an effective dose of the imaging agent-loaded platelet derivatives to the subject.

[000345] In one aspect, provided herein is a platelet derivative composition for use in the treatment of a subject having an indication selected from the group consisting of intracranial hemorrhage (I CH), traumatic brain Injury (TBI), and Hermansky Pudlak Syndrome (HPS), wherein the treatment comprises rehydrating platelet derivatives in the platelet derivative composition to form a rehydrated platelet derivative composition and administering an effective dose of the platelet derivatives in the rehydrated platelet derivative composition to the subject, wherein the platelet derivative composition comprises a population of platelet derivatives: comprising CD 41-positive platelet derivatives, wherein less than 10%, 8%, in illustrative embodiments, less than 5% of the CD 41 -positive platelet derivatives are microparticles; having a reduced propensity to aggregate such that no more than 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, or 25% of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets; and having a potency of at least 0.5, 1.0, and in illustrative embodiments, 1.5 thrombin generation potency units (TGPU) per 10⁶ platelet derivatives.

[000346] In one aspect, provided herein is a platelet derivative composition for use in the treatment of a subject having an indication of immune thrombocytopenia (ITC), or Bernard Soulier syndrome, wherein the treatment comprises rehydrating platelet derivatives in the platelet derivative composition to form a rehydrated platelet derivative composition, and administering an effective dose of the platelet derivatives in the rehydrated platelet derivative composition to the subject, wherein the platelet derivative composition comprises a population of platelet derivatives: comprising CD 41 -positive platelet derivatives, wherein less than 10%, 8%, in illustrative embodiments, less than 5% of the CD 41-positive platelet derivatives are microparticles; having a reduced propensity to aggregate such that no more than 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, or 25% of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets; and having a potency of at least 0.5, 1.0, and in illustrative embodiments, 1.5 thrombin generation potency units (TGPU) per 10⁶ platelet derivatives.

[000347] In one aspect, provided herein is a platelet derivative composition for use in the treatment of a subject having an indication selected from the group consisting of Von Willebrand disease, immune thrombocytopenia, intracranial hemorrhage (ICH), traumatic brain Injury (TBI), Hermansky Pudlak Syndrome (HPS), Chemotherapy induced thrombocytopenia (CIT), Scott syndrome, Evans syndrome, Hematopoietic Stem Cell Transplantation, Fetal and neonatal alloimmune thrombocytopenia, Bernard Soulier syndrome, Acute myeloid leukemia, Glanzmann thrombasthenia, Myelodysplastic syndrome, Hemorrhagic Shock, Coronary thrombosis (myocardial infarction), Ischemic Stroke, Arterial Thromboembolism, Wiskott Aldrich Syndrome, Venous Thromboembolism, MYH9 related disease, Acute Lymphoblastic Lymphoma (ALL), Acute Coronary Syndrome, Chronic Lymphocytic Leukemia (CLL), Acute Promyelocytic Leukemia, Cerebral Venous Sinus Thrombosis (CVST), Liver Cirrhosis, Factor V Deficiency (Owren Parahemophilia), Thrombocytopenia absent radius syndrome, Kasabach Merritt syndrome, Gray platelet syndrome, Aplastic anemia, Chronic Liver Disease, Acute radiation syndrome, Dengue Hemorrhagic Fever, Pre-Eclampsia, Snakebite envenomation, HELLP syndrome, Haemorrhagic Cystitis, Multiple Myeloma, Disseminated Intravascular Coagulation, Heparin Induced Thrombocytopenia, Pre-Eclampsia, Labor And Delivery, Hemophilia, Cerebral (Fatal) Malaria, Alexander's Disease (Factor VII Deficiency), Hemophilia C (Factor XI Deficiency), Familial hemophagocytic lymphohistiocytosis, Acute lung injury, Hemolytic Uremic Syndrome, Menorrhagia, Chronic myeloid leukemia, or any combinations thereof, wherein the treatment comprises rehydrating platelet derivatives in the platelet derivative composition to form a rehydrated platelet derivative composition and administering an effective dose of the platelet derivatives in the rehydrated platelet derivative composition to the subject, and wherein the platelet derivative composition comprises a population of platelet derivatives: comprising CD 41-positive platelet derivatives, wherein less than 10%, 8%, in illustrative embodiments, less than 5% of the CD 41 -positive platelet derivatives are microparticles; having a reduced propensity to aggregate such that no more than 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, or 25% of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets; and having a potency of at least 0.5, 1.0, and in illustrative embodiments 1.5, thrombin generation potency units (TGPU) per 10⁶ platelet derivatives.

[000348] In one aspect, provided herein is a plurality of containers each containing a platelet derivative composition in the form of a powder, wherein the platelet derivative composition comprises a population of platelet derivatives comprising CD 41 -positive platelet derivatives, wherein less than 10%, 8%, in illustrative embodiments, less than 5% of the CD 41-positive platelet derivatives are microparticles having a diameter of less than 0.3 pm, 0.4 pm, 0.5 pm, 0.6 pm, 0.7 pm, 0.8 pm, 0.9 pm, or 1 pm having a reduced propensity to aggregate such that no more than 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, or 25% of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets, and having a potency of at least 0.5, 1.0, and in illustrative embodiments, 1.5 thrombin generation potency units (TGPU) per 10⁶ platelet derivatives.

[000349] In one aspect, provided herein is a process for preparing a platelet derivative composition comprising a population of platelet derivatives, the process comprising performing tangential flow filtration (TFF) of a platelet composition in a solution to at least partially exchange the solution with a preparation agent having a pH in the range of 5.5 to 8.0 and comprising 0.4 to 35% trehalose and 2% to 8% polysucrose, wherein said TFF is performed using a 0.3 to 1 micron filter, thereby preparing a TFF- treated composition comprising 100 x 10³ - 20,000 x 10³ platelets/pL, 1000 x 10³ - 20,000 x 10³ platelets/pL, 1000 x 10³ - 10,000 x 10³ platelets/pL, 500 x 10³ - 5,000 x 10³ platelets/pL, 1000 x 10³ - 5,000 x 10³ platelets/pL, 2000 x 10³ - 8,000 x 10³ platelets/pL, or 15,000 x 10³ - 20,000 x 10³ platelets/pL, in illustrative embodiments, 10,000 x 10³ to 20,000 x 10³ platelets/pl in an aqueous medium having less than or equal to 5%, 10%, or 15% plasma protein, and having less than 10%, 8%, in illustrative embodiments, less than 5.0% microparticles having a radius less than 0.1 pm, 0.2 pm, 0.25 pm, or 0.5 pm, by scattering intensity; and freeze drying the TFF-treated composition comprising platelets in the aqueous medium to form a freeze-dried composition comprising platelet derivatives to form the platelet derivative composition, wherein the platelet derivatives in the platelet derivative composition display a potency of at least 0.5, 1.0, and in illustrative embodiments, 1.5 thrombin generation potency units (TGPU) per 10⁶ platelet derivatives, and a reduced propensity to aggregate such that no more than 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, or 25% of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets.

[000350] In one aspect, provided herein is a platelet derivative composition in the form of a powder, comprising a population of platelet derivatives having a compromised plasma membrane and a reduced propensity to aggregate such that no more than 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, or 25% of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets, wherein at least 30%, 40%, 50%, 60%, 70%, or 80% of the platelet derivatives are CD 41- positive platelet derivatives, wherein less than 1%, 2%, 3%, 4%, or 5% of the CD 41-positive platelet derivatives are microparticles having a diameter or radius of less than 0.3 pm, 0.4 pm, 0.5 pm, 0.7 pm, or 1 pm and wherein the platelet derivatives have a potency of at least 0.5, 1.0, and in illustrative embodiments, 1.5 thrombin generation potency units (TGPU) per 10⁶ platelet derivatives.

[000351] To reiterate, any embodiments herein in this section and in this specification and associated claims, can be combined and/or used in any of the aspects herein and in combination with any of the other embodiments herein. Furthermore, a “powder” recited in any aspect or embodiment can alternatively be a solid, or a composition comprising less than 1% water content in such aspect or embodiment.

[000352] In certain illustrative embodiments of a composition, or in some compositions used in or formed by a process, the platelet derivatives in a composition, as a non-limited example a powder, and/or formed by a process disclosed herein, are surrounded by a compromised plasma membrane, are positive for CD 41, and/or are 0.5 to 25.0 pm, 20.0 pm, 15.0 pm, 12.5 pm, 10.0 pm, or 2.5 pm in radius or diameter. In some embodiments, the composition comprises platelet derivatives such that at least 95% platelet derivatives positive for CD 41 have a radius or diameter in the range of 0.5 to 25.0 pm, 20.0 pm, 15.0 pm, 12.5 pm, 10.0 pm, or 2.5 pm. Such radius or diameter can be measured, for example by flow cytometry technique as known to a skilled artisan in the art.

[000353] In some embodiments of any of the aspects and embodiments herein that include platelet derivatives in a hydrated or rehydrated form, the protein concentration, or plasma protein concentration, is in the range of 0.01%-50%, 5%-50%, 5%-30%, 5-15%, 8%- 10%, 7%-10%, or 3-7% of the protein concentration of donor apheresis plasma. In some embodiments of a composition or in some compositions used in or formed by a process herein, the protein concentration, or plasma protein concentration is less than or equal to 30%, 25%, 20%, 15%, 10%, 5%, 4%, 3%, 2%, or 1% of the protein concentration of donor apheresis plasma. In some embodiments of a composition or a process herein, the protein concentration, or plasma protein concentration is less than or equal to 15%, 14%, 13%, 12%, 11%, 10%,

9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.1%, or 0.01%. In some exemplary embodiments, the protein concentration, or plasma protein concentration is less than 3% or 4%. In some embodiments, the protein concentration, or plasma protein concentration is between 0.01% and 20%, 0.01% and 15%, 0.01% and

10%, 0.01% and 5%, 0.1% and 20%, 0.1% and 15%, 0.1% and 10%, 0.1% and 5%, 1% and 20%, 1% and

15%, 1% and 10%, 1% and 5%, 2% and 10%, 2% and 5%, 2.5% and 5%, 2.5% and 7.5%, or between 3% and 5%. In some embodiments of a composition or a process herein, the protein concentration is in the range of 0.01-15%, 0.1-15%, 1-15%, 1-10%, 0.01-10%, 3-12%, or 5-10%. In some embodiments, the absorbance at 280 nm is less than or equal to 2.0 AU, or 1.90 AU, or 1.80 AU, or 1.7 AU, or 1.66 AU, or 1.6 AU when measured using a path length of 0.5 cm.

[000354] In some embodiments of any of the aspects and embodiments herein that include platelet derivatives in a powdered form, the protein concentration is in the range of 0.01-15%, 0. 1-15%, 1-15%, 1- 10%, 0.01-10%, 3-12%, or 5-10%. In some embodiments, the protein concentration is less than or equal to 25%, 20%, 15%, 10%, 7.5%, 5%, 2.5%, 1%, or 0.1%.

[000355] In some embodiments of any of the aspects and embodiments herein that include a process for preparing a platelet derivative composition, the process comprises performing TFF of a platelet composition in a solution to at least partially exchange the solution with a preparation agent having a pH in the range of 5.5 to 8.0 and comprising trehalose and polysucrose, wherein said TFF is performed using a 0.3 to 1 micron fdter, thereby preparing a TFF-treated composition.

[000356] In some embodiments of any of the aspects and embodiments herein that include a composition or in some compositions used in or formed by a process that includes a population of platelet derivatives in a hydrated or rehydrated form, the composition comprises less than 10%, 7.5%, 7%, 6%,

5%, 4.5%, 4%, 3.5%, 3%, 2.5%, 2%, 1.5%, 1.0%, 0.75%, 0.5%, 0.25%, or 0.1% (by scattering intensity) microparticles. In some embodiments, the composition comprises microparticles (by scattering intensity) in the range of 0.0I%-I0%, 0.0I%-7.5%, 0.0I%-5%, 0.1%-10%, 0.1%-5%, O.I%-4.9%, 0.5%-4.5%, !%■

10%, l%-5%, 0.01%-4%, -0.1%-4%, l%-4%, 1.5%-3%, 0. l%-3%, or l%-3%. In some embodiments, the microparticles have a diameter less than 1 pm. In illustrative embodiments, the microparticles have a radius or diameter less than 0.5 pm. In some embodiments, the microparticles have a radius or diameter in the range of 0.01-0.5 pm, 0. 1-0.5 pm, or 0.1-0.49 pm, 0.1-0.47 pm, or 0.1-0.45 pm, or 0. 1-0.4 pm, or 0.2-0.49 pm, or 0.25-0.49 pm, or 0.3-0.47 pm. In some embodiments, the radius or diameter of the microparticles is measured using flow cytometry.

[000357] In some embodiments of any of the aspects and embodiments herein that include a platelet derivative composition in a powdered form, the platelet derivative composition comprises a population of platelet derivatives comprising CD41-positive platelet derivatives, wherein less than 5%, 4.5%, 4%, 3.5%, 3%, 2.5%, 2%, 1.5%, 1%, 0.5%, or 0.1% of the CD41-positive platelet derivatives are microparticles having a diameter of less than 1 pm, 0.9 pm, 0.8 pm, 0.7 pm, 0.6 pm, 0.5 pm 0.4 pm, 0.3 pm, 0.2 pm, or 0.1 pm. In some embodiments, 0.01%-4.9%, 0.1%-4.9%, 0.5%-4.5%, 0.01%-4%, 0.1%- 4%, l%-4%, 1.5%-3%, 0. l%-3%, or l%-3% of the CD-41 -positive platelet derivatives are microparticles. In some embodiments, the platelet derivative composition comprises a population of platelet derivatives comprising CD42-positive platelet derivatives, wherein less than 5%, 4.5%, 4%, 3.5%, 3%, 2.5%, 2%, 1.5%, 1%, 0.5%, or 0.1% of the CD42-positive platelet derivatives are microparticles having a diameter of less than 1 pm, 0.9 pm, 0.8 pm, 0.7 pm, 0.6 pm, 0.5 pm, 0.4 pm, 0.3 pm, 0.2 pm, or 0.1 pm. In some embodiments, 0.01%-4.9%, 0.1%-4.9%, 0.5%-4.5%, 0.01%-4%, 0.1%-4%, l%-4%, 1.5%-3%, 0. l%-3%, or l%-3% of the CD-42 -positive platelet derivatives are microparticles. In some embodiments, the platelet derivative composition comprises a population of platelet derivatives comprising CD61 -positive platelet derivatives, wherein less than 5%, 4.5%, 4%, 3.5%, 3%, 2.5%, 2%, 1.5%, 1%, 0.5%, or 0.1% of the CD61-positive platelet derivatives are microparticles having a diameter of less than 1 pm, 0.9 pm, 0.8 pm, 0.7 pm, 0.6 pm, 0.5 pm, 0.4 pm, 0.3 pm, 0.2 pm, or 0.1 pm. In some embodiments, 0.01%-4.9%, 0.1%-4.9%, 0.5%-4.5%, 0.01%-4%, 0.1%-4%, l%-4%, 1.5%-3%, 0.1%-3%, or l%-3% ofthe CD-62- positive platelet derivatives are microparticles. In some illustrative embodiments, the microparticles are having a diameter of less than 0.5 pm. In some embodiments of any of the aspects and embodiments herein that include a platelet derivative composition in a powdered form, the diameter of the microparticles is determined after rehydrating the platelet derivative composition with an appropriate solution. In some embodiments, the amount of solution for rehydrating the platelet derivative composition is equal to the amount of buffer or preparation agent present at the step of freeze-drying. In some embodiments, the diameter of the microparticles is determined by flow cytometry.

[000358] In some embodiments of any of the aspects and embodiments herein that include a composition or in some compositions used in or formed by a process, the platelet derivatives have a radius or diameter greater than 0.25 pm, greater than 0.3 pm, greater than 0.4 pm, or in illustrative embodiments, greater than 0.5 pm. In some embodiments, the platelet derivatives have a radius or diameter greater than 0.75 pm. In some embodiments, the platelet derivatives have a radius or diameter in the range of 0.25-4 pm, 0.27-3.5 pm, 0.3-3.25 pm, 0.35-3.50 pm, or 0.4-3 pm. In illustrative embodiments, the platelet derivatives have a radius or diameter of at least 0.5 pm, for example in the range of 0.5 pm on the low end of the range to 25.0 pm, 20.0 pm, 15.0 pm, 12.5 pm, 10.0 pm, 5.0 pm or 2.5 pm on the high end of the range. In some embodiments, the diameter of the platelet derivatives is measured using flow cytometry.

[000359] In some embodiments of any of the aspects and embodiments herein that include a composition or in some compositions used in or formed by a process, the platelet derivatives are CD-41 positive. In some embodiments, at least 40%, 45%, 50%, 55%, 60%, 65%, 70%, or 75% of the platelet derivatives are CD-41 positive. In some embodiments, the platelet derivatives in the range of 35-97%, 40- 97%, 50-97%, 60-97%, 40-95%, 45-90%, 50-95%, 60-90%, or 75-95% are positive for CD-41. In some embodiments, at least 50% of the platelet derivatives are CD 41-positive platelet derivatives, wherein less than 5% of the CD 41-positive platelet derivatives are microparticles having a diameter of less than 0.5 pm, and wherein the platelet derivatives have a potency of at least 1.5 thrombin generation potency units (TGPU) per 10⁶ platelet derivatives.

[000360] In some embodiments of any of the aspects and embodiments herein that include a platelet derivative composition in a powdered form, the platelet derivatives in the platelet derivative composition have a weight percentage of at least 0.5%, 0.75%, 1%, 1.5%, 2%, 2.5% 3%, 3.5%, 4%, 4.5%, 5%, 5.5%,

6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, or 10%. In some embodiments, the platelet derivatives in the platelet derivative composition have a weight percentage in the range of 0.5 to 25%, 0.5% to 20%, 1% to

20%, 2.5% to 20%, 5% to 20%, 5% to 10%, 2.5% to 20%, 2.5% to 15%, 2.5% to 10%, or 2.5% to 7.5%

[000361] In some embodiments of the aspects and embodiments herein that include a platelet derivative composition in a powdered form, a platelet derivative composition is devoid of plasma protein. In some embodiments, the plasma protein is in the range of 0.01-15%, 0.1-15%, 1-10%, 2-15%, 3-9%, 1-5%, 1- 3%, 0.1-3%, 0.5-2%, or 0.25-2%.

[000362] In some embodiments of the aspects and embodiments herein that include a platelet derivative composition in a powdered form, a platelet derivative composition comprises a buffering agent in the range of 0.5-3%, 0.75-2.75%, 1-2.5%, or 1.5-2.5%. In some embodiments, the buffering agent is HEPES.

[000363] In some embodiments of any of the aspects and embodiments herein that include a composition or in some compositions used in or formed by a process, the platelet derivatives have an inability to increase expression of a platelet activation marker in the presence of an agonist as compared to the expression of the platelet activation marker in the absence of the agonist. In some embodiments, the platelet activation marker is selected from the group consisting of Annexin V, and CD 62. In some embodiments, the platelet activation marker is Annexin V. In some embodiments, the platelet activation marker is CD 62. In some embodiments, the agonist is selected from the group consisting of collagen, epinephrine, ristocetin, arachidonic acid, adenosine di-phosphate, and thrombin receptor associated protein (TRAP).

[000364] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process, the aqueous medium has a concentration of human leukocyte antigen (HLA) Class I antibodies that is less than 30%, 10%, 5%, 3%, or 1% of the human leukocyte antigen (HLA) Class I antibody concentration in donor apheresis plasma. In some embodiments, the aqueous medium has a concentration of human leukocyte antigen (HLA) Class II antibodies that is less than 30%, 10%, 5%, 3%, or 1% of the human leukocyte antigen (HLA) Class II antibody concentration in donor apheresis plasma. In some embodiments, the composition is negative for HLA Class I antibodies based on a regulatory agency approved test. In some embodiments, the composition is negative for HLA Class II antibodies based on a regulatory agency approved test. In some embodiments of the composition, a percentage of beads positive for HLA Class I antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, is less than 5%, 3%, or 1%. In some embodiments of the composition, a percentage of beads positive for HLA Class II antibodies, as determined for the composition by flow cytometry using beads coated with Class II HLAs is less than 5%, 3%, or 1%.

[000365] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process, the aqueous medium has a concentration of human neutrophil antigen (HNA) antibodies that is less than 30%, 10%, 5%, 3%, or 1% of the HNA antibody concentration in donor apheresis plasma. In some embodiments, the composition is negative for HNA antibodies based on a regulatory agency approved test. In some embodiments of the composition, a percentage of beads positive for HNA antibodies, as determined for the composition by flow cytometry using beads coated with HNAs is less than 5%, 3%, or 1%.

[000366] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process, a percentage of beads positive for an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, Class II HLAs, or HNAs, respectively, is less than 5%, 3%, or 1%. In some embodiments of the composition, a percentage of beads positive for HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, Class II HLAs, or HNAs, respectively, is less than 5%, 3%, or 1%. In some embodiments, the composition is negative for the antibodies selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies based on a regulatory agency approved test for the respective antibodies. In some embodiments, the composition is negative for HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies based on a regulatory agency approved test for the respective antibodies.

[000367] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process that includes a population of platelet derivatives in a hydrated or rehydrated form, the platelets or platelet derivatives in a composition are at least 100 x 10³ platelets/pL, or 200 x 10³ platelets/pL, or 400 x 10³ platelets/pL, or 1000 x 10³ platelets/pL, or 1250 x 10³ platelets/pL, or 1500 x 10³ platelets/pL, or 1750 x 10³ platelets/pL, 2000 x 10³ platelets/pL, or 2250 x 10³ platelets/pL, or 2500 x 10³ platelets/pL, or 2750 x 10³ platelets/pL, or 3000 x

10³ platelets/pL, 3250 x 10³ platelets/pL, 3500 x 10³ platelets/pL, 3750 x 10³ platelets/pL, 4000 x 10³ platelets/pL, or 4250 x 10³ platelets/pL, or 4500 x 10³ platelets/pL, or 4750 x 10³ platelets/pL, or 5000 x

10³ platelets/pL, or 5250 x 10³ platelets/pL, or 5500 x 10³ platelets/pL, or 5750 x 10³ platelets/pL, or 6000 x 10³ platelets/pL, or 7000 x 10³ platelets/pL, or 8000 x 10³ platelets/pL, or 9000 x 10³ platelets/pL, or 10,000 x 10³ platelets/pL, or 11,000 x 10³ platelets/pL, or 12,000 x 10³ platelets/pL, or 13,000 x 10³ platelets/pL, or 14,000 x 10³ platelets/pL, or 15,000 x 10³ platelets/pL, or 16,000 x 10³ platelets/pL, or 17,000 x 10³ platelets/pL, or 18,000 x 10³ platelets/pL, or 19,000 x 10³ platelets/pL, or 20,000 x 10³ platelets/pL. In some embodiments of the composition, the platelets or platelet derivatives in the composition is in the range of 100 x 10³ - 20,000 x 10³ platelets/pL, 1000 x 10³ - 20,000 x 10³ platelets/pL, 1000 x 10³ - 10,000 x 10³ platelets/pL, 500 x 10³ - 5,000 x 10³ platelets/pL, 1000 x 10³ - 5,000 x 10³ platelets/pL, 2000 x 10³ - 8,000 x 10³ platelets/pL, 10,000 x 10³ - 20,000 x 10³ platelets/pL, 15,000 x 10³ - 20,000 x 10³ platelets/pL, 5000 X 10³ to 20,000 X 10³ platelets/pl, 6000 X 10³ to 18,000 X 10³ platelets/pl or 6000 X 10³ to 15,000 X 10³ platelets/pl.

[000368] In some embodiments, the above concentrations are at any point in a process herein, such as in the volume that is freeze dried. In some embodiments, the above concentrations are for platelet- derivatives herein. It is contemplated that the platelet derivative composition in the form of a powder has to be rehydrated with a solution to determine the platelet-derivative concentration, typically in the intended volume for rehydration of a powder, e.g. freeze-dried, composition, which in illustrative embodiments is a recommended volume of a container containing the powder and/or a same volume as the composition was in before it was dried to form the powder. In some embodiments, the solution for rehydrating can be water. In some embodiments, the solution for rehydrating can be a well-known buffer. In some embodiments, the amount of solution for rehydrating the platelet derivative composition is equal to the amount of buffer or preparation agent present at the step of freeze-drying. In some embodiments, the platelet concentration is in

[000369] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process, the composition(s) comprises a population of platelet derivatives having a reduced propensity to aggregate. In certain embodiments, no more than 25%, 22.5%, 20%, 17.5%, 12.5%, 10%, 7.5%, 5%, 4%, 3%, 2%, or 1% of the platelet derivatives in the population aggregate under aggregation conditions. In an illustrative embodiment no more than 10% of the platelet derivatives in the population aggregate under aggregation conditions. Illustrative embodiments of exemplary aggregation conditions are provided herein. For example, in illustrative embodiments such aggregation conditions comprise an agonist but no platelets are present in the aggregation conditions. In some embodiments, the agonist is selected from the group consisting of collagen, epinephrine, ristocetin, arachidonic acid, adenosine di-phosphate, and thrombin receptor associated protein (TRAP). In some embodiments, the population of platelet derivatives aggregate in the range of 2-30%, 5-25%, 10-30%, 10-25%, 12.5-25%, 2-10%, 2-8%, 2-7.5%, 2-5%, 2-4%, 0-1%, 0-2%, 0- 3%, 0-4%, 0-5%, 0-7.5%, or 0-10%, or in illustrative embodiments 0 to about 1% of the platelet derivatives under aggregation conditions comprising an agonist but no platelets. It can be contemplated that aggregation conditions involve rehydrating the platelet derivative composition in an appropriate amount of water or an appropriate buffer.

[000370] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process, comprises erythrocytes in an amount lesser than 0.2 x 10⁶ erythrocytes/pL, or 0.1 x 10⁶ erythrocytes/ pL, or 0.5 x 10⁵ erythrocytes/ pL, or 0. 1 x 10⁵ erythrocytes/ pL. In some embodiments, the erythrocytes in the composition is in the range of 0. 1 x 10⁵ erythrocytes/ pL to 0.2 x 10⁶ erythrocytes/pL, or 0.5 x 10⁵ erythrocytes/ pL to 0. 1 x 10⁶ erythrocytes/pL.

[000371] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process, the aqueous medium further comprises a buffering agent, a base, a loading agent, optionally a salt, and optionally at least one organic solvent. In some embodiments, the buffering agent is HEPES (4-(2-hydroxyethyl)-l- piperazineethane sulfonic acid). In some embodiments, the base is sodium bicarbonate. In some embodiments, the loading agent is a monosaccharide, a polysaccharide, or a combination thereof. In some embodiments, the monosaccharide is selected from the group consisting of sucrose, maltose, trehalose, glucose, mannose, and xylose. In some embodiments, the monosaccharide is trehalose. In some embodiments, the polysaccharide is polysucrose. In some embodiments, the salt is sodium chloride, potassium chloride, or a combination thereof. In some embodiments, the organic solvent is selected from the group consisting of ethanol, acetic acid, acetone, acetonitrile, dimethylformamide, dimethyl sulfoxide, dioxane, methanol, n-propanol, isopropanol, tetrahydrofuran (THF), N-methyl pyrrolidone, dimethylacetamide (DMAC), and combinations thereof.

[000372] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process that includes a population of platelet derivatives in a hydrated or rehydrated form, comprises trehalose in the range of 0.4-35%, or 1- 35%, or 2-30%, 1-20%, or 1-10%, or 1-5%, or 0.5-5%. In an exemplary embodiment, the composition comprises 3.5% trehalose.

[000373] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process that includes a platelet composition in a powdered form, comprises trehalose having a weight percentage in the range of 10-60%, 15-55%, 20- 60%, 20-50%, 25-60%, 25-50%, 10-50%, 20-40%, 20-35%, or 1-20%. In some embodiments, the weight percentage of trehalose can vary on the weight percentage of other components in the composition like, polysucrose, platelet derivatives, plasma protein, and buffering agents.

[000374] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process that includes a population of platelet derivatives in a hydrated or rehydrated form, comprises polysucrose in the range of 2-8%, 2.25- 7.75%, 2.5-7.5%, or 2.5-6.5%. In an exemplary embodiment, the composition comprises 3% polysucrosc. In another exemplary embodiment, the composition comprises 6% polysucrose.

[000375] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process that includes a platelet composition in a powdered form, comprises polysucrose having a weight percentage in the range of 20-80%, 25-75%, 30-70%, 35-65%, 30-80%, or 45-60%. In some embodiments, the weight percentage of trehalose can vary on the weight percentage of other components in the composition like, trehalose, platelet derivatives, plasma protein, and buffering agents.

120

RECTIFIED SHEET (RULE 91 ) ISA/EP [000376] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process that includes a platelet composition in a powdered form, comprises trehalose and polysucrose having a combined weight percentage in the range of 30-95%, 35-95%, 40-90%, 40-90%, 45-90%, or 60-95%.

[000377] In some embodiments of any of the aspects and embodiments herein that include a composition or in some compositions used in or formed by a process herein, comprises polysucrose, the polysucrose is a cationic form of polysucrose. In some embodiments, the cationic form of polysucrose is diethylaminoethyl (DEAE)-polysucrose. In some embodiments, the polysucrose is an anionic form of polysucrose. In some embodiments, the anionic form of polysucrose is carboxymethyl -polysucrose. In some embodiments of the composition, poly sucrose has a molecular weight in the range of 70,000 MW to 400,000 MW, 100,000 MW to 400,000 MW, 200,00 MW to 400,000 MW, 80,000 MW to 350,000 MW, 100,000 MW to 300,00 MW, 100,000 MW to 200,000 MW, 120,000 MW to 200,000 MW. In some exemplary embodiments, polysucrose has a molecular weight of 150,000 MW, 160,000 MW, 170,000 MW, 180,000 MW, 190,000 MW, or 200,000 MW.

[000378] In some embodiments of any of the aspects and embodiments herein that include a composition or in some compositions used in or formed by a process herein, comprises platelet derivatives that are positive for at least one platelet activation marker selected from the group consisting of Annexin V, and CD 62. In some embodiments, the platelet derivatives are positive for at least one platelet marker selected from the group consisting of CD 41, CD 42, and CD 61. In some embodiments, the platelet derivatives are positive for CD 47. In some embodiments, the platelet derivatives are positive for Annexin V. In some embodiments, the platelet derivatives are positive for Annexin V. In some embodiments, at least 25%, 50%, or 75% of the platelet derivatives in the platelet derivative composition are Annexin V positive. In some embodiments, the platelet derivatives are positive for CD 41. In some embodiments, at least 30%, 35%, 40%, 45%, 50%, 55%, 60%, or 65% of the platelet derivatives in the platelet derivative composition are CD41 positive. In some embodiments, at least 90%, 91%, 92%, 93%, 94%, 95% 96%, 97%, 98%, or 99% platelet derivatives that are positive for CD 41 have a size in the range of 0.5-2.5 pm. In some exemplary embodiments, at least 95% platelet derivatives that are positive for CD 41 have a size in the range of 0.5-2.5 pm. In some embodiments, the platelet derivatives are positive for CD 42. In some embodiments, at least 65%, 80%, or 90% of the platelet derivatives in the platelet derivative composition are CD42 positive. In some embodiments, the platelet derivatives are positive for CD 47. In some embodiments, at least 8%, 10%, 15%, or 20% of the platelet derivatives in the platelet derivative composition are CD47 positive. In some embodiments, the platelet derivatives are positive for CD 62. In some embodiments, at least 10%, 50%, 65%, 80%, or 90% of the platelet derivatives in the platelet derivative composition are CD62 positive. In some embodiments, the platelet derivatives in the platelet derivative composition are positive for CD41, CD62, and Annexin V. In some embodiments, the platelet derivatives in the platelet derivative composition are at least 50% platelet derivatives are positive for CD41, at least 70% platelet derivatives are positive for CD62, and at least 70% platelet derivatives are positive for Annexin V.

[000379] In some embodiments of any of the aspects and embodiments herein that include a composition or in some compositions used in or formed by a process herein, the platelet derivatives have fibrinogen associated with their cell membrane. In some embodiments, the platelet derivatives have at least 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100% higher fibrinogen on their surface as compared to resting platelets, or activated platelets, or fixed platelets. In some embodiments, the platelet derivatives when analyzed for the binding of anti-fibrinogen antibody to the platelet derivatives using flow cytometry exhibit at least 10, 15, 20, 25, 30, 35, or 40 folds higher mean fluorescent intensity (MFI) in the absence of an agonist as compared to the MFI of binding of anti- fibrinogen antibody to the fixed platelets.

[000380] In some embodiments of any of the aspects and embodiments herein that include a composition or in some compositions used in or formed by a process herein that includes a population of platelet derivatives in a hydrated or rehydrated form, the platelet derivatives in the platelet derivative composition retain at least 10%, or 15%, or 20% of the lactate dehydrogenase activity of donor apheresis platelets. In some embodiments, the aqueous medium has a lactate concentration of less than 2.0 mmol/L, or 1.5 mmol/L. In some embodiments, the lactate concentration is in the range of 0.4 to 1.3 mmol/L, or 0.5 to 1.0 mmol/L.

[000381] In some embodiments of any of the aspects and embodiments herein that include a composition or in some compositions used in or formed by a process herein that includes a population of platelet derivatives in a hydrated or rehydrated form, the platelet derivatives, when at a concentration of about 4.8xl0³ particles/pL generate a thrombin peak height (TPH) of at least 25 nM, at least 50 nM, at least 75 nM, or at least 100 nM when in the presence of a reagent containing tissue factor and phospholipids. In some embodiments, the platelet derivatives, when at a concentration of about 4.8xl0³ particles/pL generate a thrombin peak height (TPH) in the range of 25-100nM, 30-80nM, or 25-75nM.

[000382] In some embodiments of any of the aspects and embodiments herein that include a composition or in some compositions used in or formed by a process, the platelet derivatives, have a potency of at least 1.25, at least 1.5, at least 1.75, at least 2.0, at least 2.25, at least 2.5 thrombin generation potency units (TGPU) per 10⁶ particles. In some embodiments, the platelet derivatives have a potency in the range of 1.2 to 2.5, 1.2 to 2.0, 1.3 to 1.5, 1.5 to 2.25, 2 to 2.5, or 2.25 to 2.5 TGPU per 10⁶ particles.

[000383] In some embodiments of any of the aspects and embodiments herein that include a composition or in some compositions used in or formed by a process, the platelet derivatives have the presence of thrombospondin (TSP-1) on their surface at a level that is at least 10%. 20%, 25%, 30%, 50%, 60%, 70%, 80%, 90%, or 100% higher than on the surface of resting platelets, or lyophilized fixed platelets. In some embodiments, the platelet derivatives have the presence of thrombospondin (TSP-1) on their surface at a level that is more than 100% higher than on the surface of resting platelets, or lyophilized fixed platelets. In some embodiments, the platelet derivatives have the presence of thrombospondin (TSP-1) on their surface at a level that is at least 50%, 60%, 70%, 80%, 90%, or 100% higher than on the surface of activated platelets, or lyophilized fixed platelets. In some embodiments, the platelet derivatives have the presence of thrombospondin (TSP-1) on their surface at a level that is more than 100% higher than on the surface of activated platelets, or lyophilized fixed platelets. In some embodiments, the platelet derivatives when analyzed for the binding of anti-thrombospondin (TSP) antibody to the platelet derivatives using flow cytometry exhibit at least 2 folds, 5 folds, 7 folds, 10 folds, 20 folds, 30 folds, 40 folds, 50 folds, 60 folds, 70 folds, 80 folds, 90 folds, or 100 folds higher mean fluorescent intensity (MFI) in the absence of an agonist as compared to the MFI of binding of anti-TSP antibody to the resting platelets. In some embodiments, the platelet derivatives when analyzed for the binding of anti-thrombospondin (TSP) antibody to the platelet derivatives using flow cytometry exhibit at least 2 folds, 5 folds, 7 folds, 10 folds, 20 folds, 30 folds, or 40 folds higher mean fluorescent intensity (MFI) in the absence of an agonist as compared to the MFI of binding of anti-TSP antibody to the lyophilized fixed platelets. In some embodiments, the platelet derivatives when analyzed for the binding of anti-thrombospondin (TSP) antibody to the platelet derivatives using flow cytometry exhibit 10-800 folds, 20-800 folds, 100-700 folds, 150-700 folds, 200-700 folds, or 250-500 folds higher mean fluorescent intensity (MFI) in the absence of an agonist as compared to the MFI of binding of anti-TSP antibody to the resting platelets. In some embodiments, the platelet derivatives when analyzed for the binding of anti-thrombospondin (TSP) antibody to the platelet derivatives using flow cytometry exhibit at least 2 folds, 5 folds, 7 folds, 10 folds, 20 folds, 30 folds, or 40 folds higher mean fluorescent intensity (MFI) in the absence of an agonist as compared to the MFI of binding of anti-TSP antibody to the active platelets. In some embodiments, the platelet derivatives when analyzed for the binding of anti- thrombospondin (TSP) antibody to the platelet derivatives using flow cytometry exhibit 2-40 folds, 5-40 folds, 5-35 folds, 10-35 folds, or 10-30 folds higher mean fluorescent intensity (MFI) in the absence of an agonist as compared to the MFI of binding of anti -TSP antibody to the active platelets.

[000384] In some embodiments of any of the aspects and embodiments herein that include a composition or in some compositions used in or formed by a process, the platelet derivatives have the presence of von Willebrand factor (vWF) on their surface at a level that is at least 10%, 20%, 25%, 30%, 50%, 60%, 70%, 80%, 90%, or 100% higher than on the surface of resting platelets, or lyophilized fixed platelets. In some embodiments, the platelet derivatives have the presence of von Willebrand factor (vWF) on their surface at a level that is more than 100% higher than on the surface of resting platelets, or lyophilized fixed platelets. In some embodiments, the platelet derivatives when analyzed for the binding of anti-von Willebrand factor (vWF) antibody to the platelet derivatives using flow cytometry exhibits at least 1.5 folds, 2 folds, or 3 folds, or 4 folds higher mean fluorescent intensity (MFI) in the absence of an agonist as compared to the MFI of binding of anti-vWF antibody to the resting platelets, or lyophilized fixed platelets. In some embodiments, the platelet derivatives when analyzed for the binding of anti-von Willebrand factor (vWF) antibody to the platelet derivatives using flow cytometry exhibits 2-4 folds, or 2.5-3.5 higher mean fluorescent intensity (MFI) in the absence of an agonist as compared to the MFI of binding of anti-vWF antibody to the resting platelets, or lyophilized fixed platelets.

[000385] In some embodiments of any of the aspects and embodiments herein that include a composition or in some compositions used in or formed by a process, the platelet derivatives lack an integrated membrane as compared to platelets. In some embodiments, the platelet derivatives are surrounded by a compromised plasma membrane. In some embodiments, the platelet derivatives are incapable of retaining more than 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, or 75% of lactate dehydrogenase as compared to lactate dehydrogenase retained in fresh platelets, or cold stored platelets, or cryopreserved platelets. In some embodiments, the platelet derivatives can retain 35%-75%, 40-70%, 45-65%, or 35-50% lactate dehydrogenase as compared to fresh platelets, or cold stored platelets, or cryopreserved platelets. In some embodiments, the platelet derivatives exhibit an increased permeability to antibodies. In some embodiments, the antibodies can be IgG antibodies.

[000386] In some embodiments of any of the aspects and embodiments herein that include a composition or in some compositions used in or formed by a process, the platelet derivatives, when at a concentration of at least about 70xl0³ particles/pL, produce an occlusion time of less than 14 minutes, or less than 12 minutes in a total thrombus-formation analysis system (T-TAS) assay. In some embodiments, the occlusion time is in the range of 1 to 13 minutes, 1 to 11 minutes, 1 to 10 minutes, or 1 to 7 minutes. [000387] In some embodiments of any of the aspects and embodiments herein that include a composition or in some compositions used in or formed by a process, the platelet derivatives in the platelet derivative composition comprise thrombosomes. In some embodiments, the platelet derivatives comprise freeze-dried platelets. In some embodiments, the platelet derivatives comprise thermally-treated freeze-dried platelets.

[000388] In some embodiments of any of the aspects and embodiments herein that include a process, comprises tangential flow fdtration (TFF), centrifugation of a starting material comprising platelet composition, or a combination thereof. In some embodiments of the process, the starting material comprising platelet composition is: a) positive for HLA Class I antibodies based on a regulatory agency approved test; or b) positive for HLA Class II antibodies based on a regulatory agency approved test; or c) positive for HNA antibodies based on a regulatory agency approved test; or two or more of a), b), and c). In some embodiments, the starting material comprising platelet composition has a protein concentration in the range of 60 to 80 mg/mL, or 65 to 75 mg/mL. In some embodiments, the starting material comprising platelet composition comprises donor blood product. In some embodiments, the donor blood product is pooled donor blood product. In some embodiments, the starting material comprising platelet composition comprises donor apheresis material.

[000389] In some embodiments of any of the aspects and embodiments herein that include a process, that does not comprise centrifugation of the starting material comprising platelets or platelet composition, the diluted starting material comprising platelets or platelet composition, the concentrated platelet composition, the TFF-treated composition, or the combination thereof. In some embodiments, the process does not comprise centrifugation of a composition comprising platelets or platelet derivatives.

[000390] In some embodiments of any of the aspects and embodiments herein that include a process, the TFF comprises concentrating. In some embodiments, the TFF comprises diafdtering. In some embodiments, the diafdtering comprises diafdtering with at least two diavolumes. In some embodiments, the diafdtering is done with at least three diavolumes, or four diavolumes, or five diavolumes, or six diavolumes. In some embodiments, the diafdtering is done with diavolumes in the range of two to ten. In some embodiments, the TFF comprises buffer exchange.

[000391] In some embodiments of any of the aspects and embodiments herein that include a process, diluting comprises diluting with an approximately equal weight (±10%) of the preparation agent.

[000392] In some embodiments of the process of any of the aspects and embodiments herein that include a process, further comprises a pathogen reduction step. In some embodiments, the pathogen reduction step occurs before the diluting of the starting material. In some embodiments, the pathogen reduction step precedes TFF.

[000393] In some embodiments of any of the aspects and embodiments herein that include a process, wherein following washing if the concentration of the platelets or cells in the TFF-treated composition is not 2000 x 10³ cells/pL (±300 x 10³), 3000 x 10³ cells/pL (±300 x 10³), 4000 x 10³ cells/pL (±300 x 10³), 5000 x 10³ cells/pL (±300 x IO³), 6000 x IO³ cells/pL (±300 x IO³), 7000 x IO³ cells/pL (±300 x IO³), 8000 x IO³ cells/pL (±300 x IO³), 10000 x IO³ cells/pL (±300 x IO³), 12000 x IO³ cells/pL (±300 x IO³), 14000 x 10³ cells/pU (±300 x IO³), 16000 x IO³ cells/pL (±300 x IO³), 18000 x IO³ cells/pL (±300 x IO³), or 20000 x IO³ cells/pU (±300 x IO³), diluting the preparation agent or concentrating the platelets or the cells to fall within this range.

[000394] In some embodiments of any of the aspects and embodiments herein that include a process, further comprises lyophilizing or freeze-drying the TFF-treated composition to form a lyophilized composition. In some embodiments, a process further comprises treating the lyophilized composition at a temperature in the range of 60-90°C, or 65-85°C, or 70-90°C for a time period in the range of 1-36 hours, or 5-30 hours, or 10-25 hours.

[000395] In some embodiments of any of the aspects and embodiments herein that include a process, the TFF is carried out using a membrane with a pore size in the range of 0.2 pm to 1 pm. In some embodiments the TFF is carried out using a membrane with pore size in the range of 0.3 pm to 1 pm, or 0.4 pm to 1 pm, or 0.4 pm to 0.8 pm, or 0.4 pm to 0.7 pm. In illustrative embodiments, the TFF is carried out using a membrane with a pore size of 0.45 pm, or 0.65 pm.

[000396] In some embodiments of any of the aspects and embodiments herein that include a process, the TFF is carried out until the absorbance at 280 nm of the aqueous medium is less than or equal to 50%, or 30%, or 10%, or 5%, or 3%, or 1% of the absorbance at 280 nm of the starting material comprising platelet composition, using a path length of 0.5 cm. In some embodiments, the TFF is carried out until the protein concentration or plasma protein concentration in the aqueous medium is less than or equal to 20%, 15%, 12.5%, 10%, 7.5%, 5%, 2.5%, or 1%. In some embodiments, the TFF is carried out until the protein concentration or plasma protein concentration is in between 0.01% and 20%, 0.01% and 15%, 0.01% and 10%, 0.01% and 5%, 0.1% and 20%, 0.1% and 15%, 0.1% and 10%, 0.1% and 5%, 1% and 20%, 1% and 15%, 1% and 10%, 1% and 5%, 2% and 10%, 2% and 5%, 2.5% and 5%, 2.5% and 7.5%, or between 3% and 5%. In some embodiments, the TFF is carried out until the absorbance at 280 nm of the aqueous medium is less than or equal to 2.0 AU, or 1.90 AU, or 1.80 AU, or 1.70 AU, or 1.66 AU, or 1.60 AU, using a path length of 0.5 cm. In some embodiments, the TFF is carried out until the platelet concentration is at least 2000 x 10³ platelets/pU, 2250 x 10³ platelets/pU, 3000 x 10³ platelets/pU, 3250 x 10³ platelets/pU, 3500 x 10³ platelets/pU, 4000 x 10³ platelets/pU, 4250 x 10³ platelets/pU, 4500 x 10³ platelets/pU, 4750 x 10³ platelets/pU, 5000 x 10³ platelets/pU, 5250 x 10³ platelets/pU, 5500 x 10³ platelets/pU, 5750 x 10³ platelets/pU, 6000 x 10³ platelets/pU, 7000 x 10³ platelets/pU, 8000 x 10³ platelets/pU, 9000 x 10³ platelets/pU, 10,000 x 10³ platelets/pU, 11,000 x 10³ platelets/pU, 12,000 x 10³ platelets/pU, 13,000 x 10³ platelets/pU, 14,000 x 10³ platelets/pU, 15,000 x 10³ platelets/pU, 16,000 x 10³ platelets/pL, 17,000 x 10³ platelets/pL, 18,000 x IO³ platelets/pL, 19,000 x IO³ platelets/pL, or 20,000 x IO³ platelets/pL.

[000397] In some embodiments of any of the aspects and embodiments herein that include a process, the TFF -treated composition comprises at least 1000 x 10³ platelets/pL, 2000 x 10³ platelets/pL, 2250 x 10³ platelets/pL, 3000 x 10³ platelets/pL, 3250 x 10³ platelets/pL, 3500 x 10³ platelets/pL, 4000 x 10³ platelets/pL, 4250 x 10³ platelets/pL, 4500 x 10³ platelets/pL, 4750 x 10³ platelets/pL, 5000 x 10³ platelets/pL, 5250 x IO³ platelets/pL, 5500 x IO³ platelets/pL, 5750 x IO³ platelets/pL, 6000 x IO³ platelets/pL, 7000 x IO³ platelets/pL, 8000 x IO³ platelets/pL, 9000 x IO³ platelets/pL, 10,000 x IO³ platelets/pL, 11,000 x IO³ platelets/pL, 12,000 x IO³ platelets/pL, 13,000 x IO³ platelets/pL, 14,000 x IO³ platelets/pL, 15,000 x IO³ platelets/pL, 16,000 x IO³ platelets/pL, 17,000 x IO³ platelets/pL, 18,000 x IO³ platelets/pL, 19,000 x IO³ platelets/pL, or 20,000 x IO³ platelets/pL. In some embodiments, the TFF- treated composition comprises 1000 x IO³ platelets/pL to 20,000 x IO³ platelets/pL, 10,000 x IO³ platelets/pL to 20,000 x IO³ platelets/pL, 5000 x IO³ platelets/pL to 20,000 x IO³ platelets/pL, or 5000 x IO³ platelets/pL to 10,000 x IO³ platelets/pL.

[000398] In some embodiments of any of the aspects and embodiments herein that include a process, the TFF comprises diafdtering with a preparation agent comprising a buffering agent, a base, a loading agent, optionally a salt, and optionally at least one organic solvent. In some embodiments of the process, the TFF comprises buffer exchange into a preparation agent comprising a buffering agent, a base, a loading agent, optionally a salt, and optionally at least one organic solvent. In some embodiments, the buffering agent is HEPES (4-(2-hydroxyethyl)-l-piperazineethanesulfonic acid). In some embodiments, the base is sodium bicarbonate. In some embodiments, the loading agent is a monosaccharide, a polysaccharide, or a combination thereof. In some embodiments, the monosaccharide is selected from the group consisting of sucrose, maltose, trehalose, glucose, mannose, xylose, and combinations thereof. In some embodiments, the monosaccharide is trehalose. In some embodiments, the polysaccharide is polysucrose. In some embodiments, the salt is sodium chloride, potassium chloride, or a combination thereof. In some embodiments, the organic solvent is selected from the group consisting of ethanol, acetic acid, acetone, acetonitrile, dimethylformamide, dimethyl sulfoxide, dioxane, methanol, n-propanol, isopropanol, tetrahydrofuran (THF), N-methyl pyrrolidone, dimethylacetamide (DMAC), and combinations thereof.

[000399] In some embodiments of any of the aspects and embodiments herein that include a process, the preparation agent has a pH in the range of 5.5 to 8.0, or 6.0 to 8.0, or 6.0 to 7.5. In an illustrative embodiment, the preparation agent has a pH of 6.5. In another illustrative embodiment, the preparation agent has a pH of 7.4.

[000400] In some embodiments of any of the aspects and embodiments herein that include a process, that does not comprise a step for fixing the platelets, or platelet derivatives. In some embodiments, the process does not comprise fixing the platelets, or platelet derivatives using a fixative agent known in the art for fixing the platelets or platelet derivatives. In some embodiments, the process does not comprise contacting the platelets, or platelet derivatives with at least one fixative agent. In some embodiments, the fixative agent is an aldehyde. In some embodiments, the fixative agent is an alcohol. In illustrative embodiments, the fixative agent is selected from the group consisting of formaldehyde, paraformaldehyde, glutaraldehyde, and isopropanol.

[000401 ] In some embodiments of any of the aspects and embodiments herein that include a process, further comprises lyophilizing the composition comprising platelets or platelet derivatives.

[000402] In some embodiments of any of the aspects and embodiments herein that include a process, further comprises cryopreserving the composition comprising platelets or platelet derivatives.

[000403] In some embodiments of any of the aspects and embodiments herein that include a process, further comprises thermally treating the composition comprising platelets or platelet derivatives.

[000404] In some of the embodiments of any of the aspects and embodiments herein that include a process, the TFF is performed at a temperature in the range of 20 °C to 37 °C, or 25 °C to 37 °C, or 20 °C to 35 °C, or 25 °C to 35 °C.

[000405] In some embodiments of any of the aspects and embodiments herein that include a process, a percentage of beads positive for an antibody selected from the group consisting of HLA Class I antibodies, HLA Class II antibodies, and HNA antibodies, as determined for the composition by flow cytometry using beads coated with Class I HLAs, Class II HLAs, or HNAs, respectively, is reduced by at least 50%, or by at least 75%, or by at least 90%, or by at least 95%, as compared to a similar composition not prepared by a process comprising tangential flow filtration of a blood product composition, centrifugation of a blood product composition, or a combination thereof.

[000406] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process, the platelet derivatives are derived from human platelets and are positive for at least one marker selected from the group consisting of CD 41, CD 42, and CD 61. In some embodiments, the platelet derivatives are derived from human platelets that are positive for CD 41. In some embodiments, embodiments, the platelet derivatives are derived from human platelets that are positive for CD 42. In some embodiments, embodiments, the platelet derivatives are derived from human platelets that are positive for CD 61. In some illustrative embodiments, the platelet derivatives are derived from human platelets that are positive for CD 41, CD 42, and CD 61. [000407] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process, the platelet derivatives are derived from a non-human animal. In some embodiments, the non-human animal is selected from the group consisting of canines, equines, and felines. In some exemplary embodiments, the platelet derivatives are derived from canines.

[000408] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process that includes a population of platelet derivatives a powdered form, the platelet derivative composition comprises no more than 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4.0%, 4.5%, or 4.9% residual moisture. In some embodiments, wherein the platelet derivative composition is in a powdered form, the platelet derivative composition comprises residual moisture in the range of 0.1-2%, 0.2-1.5%, 0.5-1.5%, 0.75-1.25%, 2-3%, 2.5-4.9%, 3-4.5%, 1.5-3%, or 1-2% residual moisture. In some illustrative embodiments, the platelet derivative composition comprises no more than 0.5% residual moisture. [000409] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process that includes a plurality of containers each filled with a platelet derivative composition in the form of a powder, the platelet derivative composition in at least one of the plurality of containers comprises or is associated with a first protein from a first gene that has a different amino acid sequence than found in all the versions of the first protein from the first gene in the platelet derivative composition in one or more other containers of the plurality.

[000410] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process that includes a plurality of containers each filled with a platelet derivative composition in the form of a powder, the at least one container comprises a first lot of platelet derivatives and the one or more other containers comprise a second lot of platelet derivatives. In some embodiments, plurality of containers comprises the platelet derivative composition from at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 different lots, wherein the platelet derivative composition in at least 2 of the lots have a different amino acid sequences for at least one protein of a collection of protein gene products from a corresponding collection of encoding genes. In illustrative embodiments all, of the lots have a different amino acid sequences for at least one protein of a collection of protein gene products from a corresponding collection of encoding genes. In some embodiments, the amino acid difference(s) is at one or more residues corresponding to amino acid residues encoded by a non-synonymous single nucleotide polymorphism (SNP).

[000411] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process that includes a plurality of containers each filled with a platelet derivative composition in the form of a powder, each of the plurality of containers are purged with at least one inert gas. In some embodiments, the inert gas can be argon, or nitrogen.

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RECTIFIED SHEET (RULE 91 ) ISA/EP [000412] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process that includes a plurality of containers each filled with a platelet derivative composition in the form of a powder, the platelet derivative composition from the at least 2 lots have different amino acid sequences for at least one protein of a collection of protein gene products from a corresponding collection of encoding genes. In some embodiments, the different amino acid sequences differ at one or more residues corresponding to amino acid residues encoded by a non-synonymous single nucleotide polymorphism (SNP). In some embodiments, the platelet derivative composition is in a container, and wherein the container is filled with at least one inert gas.

[000413] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process that includes a plurality of containers each filled with a platelet derivative composition in the form of a powder, the amount of plasma protein in the powder of any two containers chosen from different lots, differs by less than 50%, 40%, 30%, 20%, 10%, 5%, 2%, 1%, or 0.5%.

[000414] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process that includes a plurality of containers each filled with a platelet derivative composition in the form of a powder, the amount of microparticles that are less than 0.5 pm in the powder of any two containers chosen from different lots, differs by less than 50%, 40%, 30%, 20%, 10%, 5%, 2%, 1%, or 0.5%.

[000415] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process that includes a plurality of containers each filled with a platelet derivative composition in the form of a powder, the platelet derivative composition from the at least 2 lots have different amino acid sequences for at least one, two, three, four, or five protein of a collection of protein gene products from a corresponding collection of encoding genes. In some embodiments, the different amino acid sequences differ at one or more residues corresponding to amino acid residues encoded by a non-synonymous single nucleotide polymorphism (SNP).

[000416] In some embodiments of any of the aspects and embodiments herein that includes a plurality of containers each filled with a platelet derivative composition in the form of a powder, the containers can vary in volume from 5-100 ml, 10-90 ml, 25-75 ml, or 5-40 ml. In some embodiments, the volume of containers can be 5 ml, 10 ml, 15 ml, 20 ml, 25 ml, 30 ml, 35 ml, 40 ml, 45 ml, 50 ml, 55 ml, 60 ml, 65 ml, 70 ml, 75 ml, 80 ml, 85 ml, 90 ml, 95 ml, or 100 ml. In some embodiments, the volume of containers can be above 100 ml, for example, 125 ml, 150 ml, 175 ml, or 200 ml. In some illustrative embodiments, the volume of vials is 30 ml. In some other illustrative embodiments, the volume of vials is 10 ml. In some embodiments, the plurality of containers can have 10 -500 vials, 25-450 vials, 50-350 vials, 100- 300 vials, or 150-250 vials. In some embodiments, the plurality of containers can have 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 250, 300, 350, 400, 450, or 500 vials. In some embodiments, the plurality of containers can be increased to more than 500 as per the requirements, for example, 600, 700, 800, 900, or 1000 vials. In some embodiments, the number of vials can be 10-1000, 50-1000, 100-900, 200-800, or 150-700, or 150-500 vials. The number of vials in which a platelet derivative composition as per one of the embodiments, or aspects described herein can be fdled and/or present can vary with the manufacturing requirements and the amount of starting material comprising platelets.

[000417] In some embodiments of any of the aspects and embodiments herein that includes a plurality of containers each fdled with a platelet derivative composition in the form of a powder, the amount of platelet derivatives when the plurality of containers is taken as a whole can be 1 X 10⁹ to 1 X 10¹⁶, 1 X 10¹⁰ to 1 X 10¹⁵, 1 X 10¹¹ to 1 X 10¹⁵, 1 X 10¹² to 1 X 10¹⁶, or 1 X 10¹³ to 1 X 10¹⁵.

[000418] In some embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process, the platelet derivatives are allogenic platelet derivatives. In some embodiments, the platelet derivatives are allogenic platelet derivative product. In some embodiments, a platelet derivative composition as per any of the embodiments or aspects herein, is a composition comprising allogenic platelet derivatives. In some embodiments, a platelet derivative composition as described herein is a U.S. FDA-approved product comprising allogenic platelet derivative composition. In some embodiments, a platelet derivative composition as described herein is a European EMA-approved product comprising allogenic platelet derivative composition. In some embodiments, a platelet derivative composition as described herein is a China FDA-approved product comprising an allogenic platelet derivative composition.

[000419] In some embodiments of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process, or a process for preparing a platelet derivative composition, the platelets in the starting material can be donated from a human subject. In some embodiments, the human subject can be a male, or a female. In some embodiments, the platelets can be a pooled product from a number of male and female donors. In some embodiments, from a total of 100 donors, any number can be female donors, ranging from 0-100, 5-95, 10-90, 20-80, 30-70, or 40-60, and the rest can be male donors.

[000420] In some embodiments of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process, or a process for preparing a platelet derivative composition, a starting material can comprise 10-500 units of platelets. In some embodiments, the starting material can comprise 20-500 units, 30-400 units, 40-350 units, or 50-200 units. In some embodiments, the units can be a pooled platelet product from multiple donors as described herein.

[000421 ] In some embodiments of any of the aspects and embodiments herein that include a method for treating a clotting-related disorder in a subject, said method comprising administering to the subject a therapeutically effective amount of the platelet derivative composition of any of the aspects or embodiments herein, or the platelet derivative composition prepared by any of the process described in the aspects or embodiments herein. In some embodiments, the clotting-related disorder is selected from the group consisting of Von Willebrand Disease, hemophilia, thrombasthenia, thrombocytopenia, thrombocytopenic purpura, trauma, or a combination thereof. In some embodiments, the composition is passed through a fdter of 18 pm before administering to the subject.

[000422] In some embodiments, the platelet derivative composition of any of the aspects or embodiments herein is provided for use in the treatment of a disorder selected from the group consisting of alopecia areata, Von Willebrand Disease, hemophilia, thrombasthenia, thrombocytopenia, thrombocytopenic purpura, trauma, or a combination thereof.

[000423] In some embodiments, the platelet derivatives as described herein can be used for healing wounds in a subject. In some embodiments, there is provided a method for healing a wound in a subject, comprising administering a therapeutically effective amount of a platelet derivative composition of any of the aspects or embodiments herein, or the platelet derivative composition prepared by any of the process described in the aspects or embodiments herein, to the subject. In some embodiments, the platelet derivative composition of any of the aspects or embodiments herein is provided for use in wound healing in a subject.

[000424] In some embodiments, the platelet derivative composition of any of the aspects or embodiments herein can be used in treating a coagulopathy in a subject that has been administered or is being administered an antiplatelet agent. In some embodiments, the platelet derivative composition of any of the aspects or embodiments herein is provided for use an anti-platelet reversal agent. In some embodiments, the platelet derivative composition of any of the aspects or embodiments herein can be used in treating a coagulopathy in a subject that has been administered or is being administered an anticoagulant agent. In some embodiments, the platelet derivative composition of any of the aspects or embodiments herein is provided for use an anti -coagulant reversal agent.

[000425] In some embodiments, there is provided a method of treating a subject, the method comprising administering to the subject in need thereof, an effective amount of any of the platelet derivative compositions disclosed herein, or the platelet derivative composition prepared by any of the methods disclosed herein, wherein the subject has been treated or is being treated with an antiplatelet agent and/or an anti -coagulant, and wherein the method for treating is a) a method for restoring normal hemostasis in the subject; b) for treating a coagulopathy in the subject; or c) for preparing the subject for surgery. In some embodiments, the method of treating is the method of restoring normal hemostasis in the subject. In some embodiments, the method of treating is the method for treating the coagulopathy in the subject. In some embodiments, the method of treating is the method for preparing the subject for surgery. In some embodiments of any of tire methods for treating aspects herein, wherein the subject is being treated with an antiplatelet agent, the antiplatelet agent is selected from the group consisting of aspirin, cangrelor, ticagrelor, clopidogrel, prasugrel, eptifibatide, tirofiban, abciximab, a supplement, and a combination thereof. In some embodiments of any of the methods for treating aspects herein, wherein the subject is being treated with an antiplatelet agent, the antiplatelet agent is selected from the group consisting of aspirin, cangrelor, ticagrelor, clopidogrel, prasugrel, eptifibatide, tirofiban, abciximab, terutroban, picotamide, elinogrel, ticlopidine, ibuprofen, vorapaxar, atopaxar, and a combination thereof. In some embodiments of any of the methods for treating aspects herein, wherein the subject is being treated with an antiplatelet agent, the antiplatelet agent is selected from the group consisting of aspirin, cangrelor, ticagrelor, clopidogrel, prasugrel, eptifibatide, tirofiban, abciximab, terutroban, picotamide, elinogrel, ticlopidine, ibuprofen, vorapaxar, atopaxar, cilostazol, prostaglandin El, epoprostenol, dipyridamole, treprostinil sodium, sarpogrelate, and a combination thereof.

[000426] In some embodiments of any of the methods for treating aspects herein, wherein the subject is being treated with an anticoagulant, the anticoagulant is selected from the group consisting of dabigatran, argatroban, hirudin, rivaroxaban, apixaban, edoxaban, fondaparinux, warfarin, heparin, a low molecular weight heparin, a supplement, and a combination thereof. In some embodiments of any of the methods for treating aspects herein, wherein the subject is being treated with an anticoagulant, the anticoagulant is selected from the group consisting of dabigatran, argatroban, hirudin, rivaroxaban, apixaban, edoxaban, fondaparinux, warfarin, heparin, low molecular weight heparins, tifacogin, Factor VIlai, SB249417, pegnivacogin (with or without anivamersen), TTP889, idraparinux, idrabiotaparinux, SR23781A, apixaban, bctrixaban, lepirudin, bivalirudin, ximclagatran, phcnprocoumon, acenocoumarol, indandioncs, fluindione, a supplement, and a combination thereof. In some embodiments of any of the methods for treating aspects herein, the administering comprises administering topically, parenterally, intravenously, intramuscularly, intrathecally, subcutaneously or intraperitoneally. In some embodiments of any of the methods for treating aspects herein, where the composition is in the form of a powder, the method further includes, before the administering, rehydrating the composition. In some embodiments provided herein is use of any of the platelet derivative compositions herein, in the manufacture of a kit for performing any of the methods of treating provided herein.

[000427] In some embodiments, there is provided a composition comprising platelets or platelet derivatives prepared by any of the process described in any of the aspects or embodiments herein. In some

133

RECTIFIED SHEET (RULE 91 ) ISA/EP embodiments, there is provided a composition comprising platelets or platelet derivatives and an aqueous medium prepared by any of the process described in any of the aspects or embodiments herein. In some of the embodiments, there is provided a composition comprising freeze-dried platelets prepared by any of the process described in any of the aspects or embodiments herein. In some of the embodiments, there is provided a composition comprising thrombosomes prepared by any of the aspects or embodiments herein. In some of the embodiments of any of the aspects and embodiments herein that include a composition, or in some compositions used in or formed by a process, a composition prepared by a process comprising tangential flow fdtration (TFF) of a starting material comprising platelets, centrifugation of a starting material comprising platelets, or a combination thereof. In some embodiments, the centrifugation comprises centrifugation at 1400 x g to 1550 x g, or 1450 x g to 1500 x g. In some embodiments, the composition is prepared by a process that does not comprise centrifugation.

[000428] In some embodiments of the aspects and embodiments herein that include a platelet derivative composition, or in some compositions used in or formed by a process, or a process for preparing a platelet derivative composition, or a method for treating a subject, or a platelet derivative composition comprising platelet derivatives for use as a medicament in treating a subject, a therapeutically effective dose of platelet derivatives is based on units of thrombin generation activity administered per kilogram of body weight of the subject. In further embodiments of these embodiments the effective dose is not based on the number of platelet derivatives delivered to the subject. In some embodiments of any aspect or embodiment herein the effective dose is based on both A) units of thrombin generation activity administered per kilogram of body weight of the subject; and B) the number of platelet derivatives administered to the subject. In some embodiments of any aspect or embodiment herein the effective dose is based on the weight of the subject.

[000429] In some embodiments of any aspect or embodiment herein the subject is suffering from a condition, or a disease selected from the group including only thrombocytopenia, hematologic malignancy, bone marrow aplasia, myeloproliferative disorders, myelodysplastic syndromes, and platelet refractoriness. In some embodiments, the subject is suffering from thrombocytopenia. In some embodiments, the subject is suffering from hematologic malignancy. In some embodiments, the subject is suffering from bone marrow aplasia. In some embodiments, the subject is suffering from myeloproliferative disorders. In some embodiments, the subject is suffering from myelodysplastic syndromes. In some embodiments, the subject is suffering from platelet refractoriness. In some embodiments, the subject is suffering from two or more of the disease or condition selected from the group consisting of thrombocytopenia, hematologic malignancy, bone marrow aplasia, myeloproliferative disorders, myelodysplastic syndromes, and platelet refractoriness. [000430] In some embodiments of any aspect or embodiment herein a therapeutically effective dose or amount of the platelet derivatives in a platelet derivative composition is in the range of 1.0 X 10⁷ to 1.0 X 10¹²/kg of the subject.

[000431 ] In some embodiments of any aspect or embodiment herein a therapeutically effective dose or amount of the platelet derivatives is an amount that has a potency in the range of 250 to 5000 TGPU per kg of the subject.

[000432] In some embodiments of any aspect or embodiment herein, a method of treatment or a composition for use as a medicament as described herein, a method or a medicament leads to cessation or decrease in bleeding at a primary bleeding site at 12 hours, 24 hours, 48 hours, 72 hours, 4 days, 5 days, 6 days, and/or 7 days after administering the platelet derivative composition. In some embodiments, the primary bleeding site is based upon the most severe bleeding location of the subject within 12 hours prior to administering the platelet derivative composition. In some embodiments, the administering involves infusing a platelet derivative composition. In some embodiments, a platelet derivative composition is administered on Day 1 of the treatment. In some embodiments, the cessation or decrease is evidenced by an ordinal change in WHO bleeding score of the subject evaluated at 24 hours after administering the platelet derivative composition to the subject. In some embodiments, a method or a medicament as described herein leads to cessation or decrease in bleeding at bleeding sites other than primary bleeding site at 12 hours, 24 hours, 48 hours, 72 hours, 4 days, 5 days, 6 days, and 7 days after administering the platelet derivative composition.

[000433] In some embodiments of any aspect or embodiment herein, a method of treatment or a composition for use as a medicament as described herein, a method or a medicament leads to an increase in platelet count in the subject at 12 hours, 24 hours, 48 hours, 72 hours, 4 days, 5 days, 6 days, and 7 days after administering the platelet derivative composition. In some embodiments, the increase is at least 500 plate lets/pl, 1000 platelets/pl, 2000 platelets/pl, 3000 platelets/pl, 4000 platelets/pl, 5000 platelets/pl, 6000 platelets/pl, 7000 platelets/pl, 8000 platelets/pl, 9000 platelets/pl, or 10000 platelets/pl in the subject. In some embodiments, the increase is in the range of 500 to 10000 platelets/pl, 1000 to 10000 platelets/pl, 2000 to 8000 platelets/pl, or 3000 to 7000 platelets/pl in the subject.

[000434] In some embodiments of any aspect or embodiment herein, a method of treatment or a composition for use as a medicament as described herein, a method or a medicament leads to changes, or in some embodiments, does not lead to changes, in one or more markers of endothelial cell injury in the subject from a pre-administration time through 12 hours to 35 days, 24 hours to 32 days, 24 hours to 30 days, or 48 hours to 28 days after administering the platelet derivative composition. In some embodiments, the method or the medicament leads to changes, or in some embodiments, does not lead to changes, in one or more markers of endothelial cell injury in the subject at 72 hours after administering the platelet derivative composition. In some embodiments, the one or more markers of endothelial cell injury is selected from the group consisting of Syndecan-1, hyaluronan, thrombomodulin, vascular endothelial growth factor (VEGF), interleukin 6, and sVE cadherin. In some embodiments, the method or the medicament leads to changes in two or more markers, three or markers, four or more markers, five or more markers, or all of the markers selected from the group consisting of Syndecan-1, hyaluronan, thrombomodulin, vascular endothelial growth factor (VEGF), interleukin 6, and sVE cadherin. In some embodiments, the changes can be an increase or a decrease in the markers of endothelial cell injury in the subject as compared to a control.

[000435] In some embodiments of any aspect or embodiment herein, a method of treatment or a composition for use as a medicament as described herein, a method or a medicament leads to acceptable measures of coagulation in the subject at 12 hours to 35, 24 hours to 32 days, 24 hours to 30 days, or 48 hours to 28 days after administering the platelet derivative composition. In some embodiments, a method or a medicament leads to acceptable measures of coagulation in the subject at 72 hours after administering the platelet derivative composition. In some embodiments, the acceptable measure of coagulation includes one or more, two or more, three or more, four or more, five or more, or all of prothrombin time (PT), international normalized ratio (INR), fibrinogen, D-dimer, activated partial thromboplastin time (aPTT), and thromboelastography (TEG) or rotational thromboelastometry (ROTEM). In some embodiments, a method or a medicament leads to an increase or a decrease in the acceptable measure of coagulation in the subject as compared to a control.

[000436] In some embodiments of any aspect or embodiment herein, a method of treatment or a composition for use as a medicament as described herein, a method or a medicament leads to acceptable measures of hematology in the subject from a pre-administration time through 12 hours to 35 days, 24 hours to 32 days, 24 hours to 30 days, or 48 hours to 28 days after administering the platelet derivative composition. In some embodiments, the acceptable measures of hematology are one or more, two or more, three or more, four or more, five or more, or all selected from the group consisting of Prothrombin Fragment 1+2, thrombin generation assay (TGA), Thrombopoietin, activated Protein C, tissue plasminogen activator (TP A), and/or plasminogen activator inhibitor (PAI). In some embodiments, the acceptable measures of hematology can be an increase or a decrease in the subject as compared to a control.

[000437] In some embodiments of any aspect or embodiment herein, a method of treatment or a composition for use as a medicament as described herein, a method or a medicament leads to survival of the subject without WHO Grade 2A or greater bleeding during the first 3, 4, 5, 6, 7, 8, 9, or 10 days after administering of a platelet derivative composition. [000438] In some embodiments of any aspect or embodiment herein, a method of treatment or a composition for use as a medicament as described herein, administering is performed in a maximum of 2, 3, 4, 5, 6, 7, 8, 9, or 10 doses in a 72-hour period of treatment. In some embodiments, the subject has a count of total circulating platelets (TCP) between 5,000 to 100,000 platelets/pl, 10,000 to 90,000 platelets/pl, 10,000 to 80,000 platelets/pl, or 10,000 to 70,000 platelets/pl of blood at the time of administering. In some embodiments, the subject is undergoing one or more, two or more, three or more, or all of chemotherapy, immunotherapy, radiation therapy or hematopoietic stem cell transplantation at the time of administering. In some embodiments, the subject is refractory to platelet transfusion, wherein refractory is a two 1-hour CCI [corrected count increment] of <5000 on consecutive transfusions of liquid stored platelets. In some embodiments, the subject has a WHO bleeding score of 2 excluding cutaneous bleeding.

[000439] In some embodiments of any aspect or embodiment herein the subject at the time of administering has two or more, or all of: confirmed diagnosis of hematologic malignancy, myeloproliferative disorder, myelodysplastic syndrome, or aplasia; undergoing chemotherapy, immunotherapy, radiation therapy or hematopoietic stem cell transplantation; or refractory to platelet transfusion wherein refractory is a two 1-hour CCI of <5000 on consecutive transfusions of liquid stored platelets.

[000440] In some embodiments of any aspect or embodiment herein the administering confers an improved survival at 10, 15, 20, 25, 30, 35, 40, 45, or 50 days after administering the platelet derivatives. In some embodiments of any aspect or embodiment herein the administering leads to a decrease in administration of secondary blood products, platelets, or platelet derivatives to the subject for the first 5, 6, 7, 8, 9, or 10 days after the administering of the platelet derivatives.

[000441 ] In some embodiments of any aspect or embodiment herein that include delivering platelet derivatives to a subject, or administering platelet derivatives to a subject, or treating a subject, or use of platelet derivative composition or platelet derivatives as described in any of the aspects or embodiments, the subject is having an indication selected from the group consisting of Von Willebrand disease, immune thrombocytopenia, Intracranial hemorrhage (ICH), Traumatic brain injury (TBI), Hermansky Pudlak Syndrome (HPS), Chemotherapy induced thrombocytopenia (CIT), Scott syndrome, Evans syndrome, Hematopoietic Stem Cell Transplantation, Fetal and neonatal alloimmune thrombocytopenia, Bernard Soulier syndrome, Acute myeloid leukemia, Glanzmann thrombasthenia, Myelodysplastic syndrome, Hemorrhagic Shock, Coronary thrombosis (myocardial infarction), Ischemic Stroke, Arterial Thromboembolism, Wiskott Aldrich Syndrome, Venous Thromboembolism, MYH9 related disease, acute lymphoblastic lymphoma (ALL), Acute Coronary Syndrome, Chronic Lymphocytic Leukemia (CLL), Acute Promyelocytic Leukemia, Cerebral Venous Sinus Thrombosis (CVST), Liver Cirrhosis, Factor V Deficiency (Owren Parahemophilia), Thrombocytopenia absent radius syndrome, Kasabach Merritt syndrome, Gray platelet syndrome, Aplastic anemia, Chronic Liver Disease, Acute radiation syndrome, Dengue Hemorrhagic Fever, Pre-Eclampsia, Snakebite envenomation, HELLP syndrome, Haemorrhagic Cystitis, Multiple Myeloma, Disseminated Intravascular Coagulation, Heparin Induced Thrombocytopenia, Pre-Eclampsia, Labor And Delivery, Hemophilia, Cerebral (Fatal) Malaria, Alexander's Disease (Factor VII Deficiency), Hemophilia C (Factor XI Deficiency), Familial hemophagocytic lymphohistiocytosis, Acute lung injury, Hemolytic Uremic Syndrome, Menorrhagia, Chronic myeloid leukemia, or any combinations thereof. In some embodiments, an indication is Von Willebrand disease. In some embodiments, an indication is Immune thrombocytopenia. In some embodiments, an indication is Chemotherapy induced thrombocytopenia (CIT). In some embodiments, an indication is Fetal and neonatal alloimmune thrombocytopenia.

[000442] In some embodiments of any aspect or embodiments herein that include an indication, the indication is selected from the group consisting of Von Willebrand disease, Immune thrombocytopenia, Intracranial hemorrhage (ICH), Traumatic brain injury (TBI), Hermansky Pudlak Syndrome (HPS), Chemotherapy induced thrombocytopenia (CIT), Scott syndrome, Evans syndrome, Hematopoietic Stem Cell Transplantation, Fetal and neonatal alloimmune thrombocytopenia, Bernard Soulier syndrome, Acute myeloid leukemia, Glanzmann thrombasthenia, Myelodysplastic syndrome, Hemorrhagic Shock, Coronary thrombosis (myocardial infarction), Ischemic Stroke, Arterial Thromboembolism, Wiskott Aldrich Syndrome, Venous Thromboembolism, MYH9 related disease, Acute Lymphoblastic Lymphoma (ALL), Acute Coronary Syndrome, Chronic Lymphocytic Leukemia (CLL), Acute Promyelocytic Leukemia, Cerebral Venous Sinus Thrombosis (CVST), Liver Cirrhosis, Factor V Deficiency (Owren Parahemophilia), Thrombocytopenia absent radius syndrome, Kasabach Merritt syndrome, Gray platelet syndrome, Aplastic anemia, or combinations thereof.

[000443] In some embodiments of any aspect or embodiments herein that include an indication, the indication is selected from the group consisting of Chronic Liver Disease, Acute radiation syndrome, Dengue Hemorrhagic Fever, Pre-Eclampsia, Snakebite envenomation, HELLP syndrome, Haemorrhagic Cystitis, Multiple Myeloma, Disseminated Intravascular Coagulation, Heparin Induced Thrombocytopenia, Pre-Eclampsia, Labor And Delivery, Hemophilia, Cerebral (Fatal) Malaria, Alexander's Disease (Factor VII Deficiency), Hemophilia C (Factor XI Deficiency), Familial hemophagocytic lymphohistiocytosis, Acute lung injury, Hemolytic Uremic Syndrome, Menorrhagia, Chronic myeloid leukemia, or any combinations thereof.

[000444] In some embodiments of any aspect or embodiments herein that include an indication, the indication is selected from the group consisting of Fetal and neonatal alloimmune thrombocytopenia, intracranial hemorrhage (ICH), traumatic brain injury (TBI), Von Willebrand disease, Immune thrombocytopenia, and the indication is not treatable by administering unmodified platelets. In some embodiments, the indication is Von Willebrand disease, and wherein the indication is not treatable by administering unmodified platelets. In some embodiments, the indication is Immune thrombocytopenia, and wherein the indication is not treatable by administering unmodified platelets. In some embodiments, the indication is Fetal and neonatal alloimmune thrombocytopenia, wherein the indication is not treatable by administering unmodified platelets. In some embodiments, the indication is intracranial hemorrhage (ICH), and wherein the indication is not treatable by administering unmodified platelets. In some embodiments, the indication is traumatic brain injury (TBI), and wherein the indication is not treatable by administering unmodified platelets.

[000445] In some embodiments of any aspect or embodiment herein that include delivering platelet derivatives to a subject, or administering platelet derivatives to a subject, or treating a subject, or use of platelet derivative composition or platelet derivatives as described in any of the aspects or embodiments, the subject is having an indication that, typically cannot be treated with unmodified platelet preparation but can be treated with a platelet derivative composition as described herein. In some embodiments, such type of indication is Von Willebrand disease, Immune thrombocytopenia, Intracranial hemorrhage (ICH), Traumatic brain injury (TBI), Hermansky Pudlak Syndrome (HPS), Chemotherapy induced thrombocytopenia (CIT), Scott syndrome, Evans syndrome, Hematopoietic Stem Cell Transplantation, Fetal and neonatal alloimmune thrombocytopenia, Bernard Soulier syndrome, Acute myeloid leukemia, or combinations thereof.

[000446] In some aspects, provided herein is a method of treating immune thrombocytopenia in a subject, the method comprises administering an effective dose of freeze-dried platelet derivatives, in a platelet derivative composition, to the subject. In some aspects, provided herein is a method of treating intracranial hemorrhage (ICH) in a subject, the method comprises administering an effective dose of freeze-dried platelet derivatives, in a platelet derivative composition, to the subject. In some aspects, provided herein is a method of treating traumatic brain injury (TBI) in a subject, the method comprises administering an effective dose of freeze-dried platelet derivatives, in a platelet derivative composition, to the subject.

[000447] In some embodiments of any aspect or embodiment herein that include delivering platelet derivatives to a subject, or administering platelet derivatives to a subject, or treating a subject, or use of platelet derivative composition or platelet derivatives as described in any of the aspects or embodiments, platelet derivatives can have an effective dose or a therapeutically effective dose in the range of 1.0 x 10⁷ to 1.0 x 10¹¹ particles/kg of the subject. In some embodiments, platelet derivatives can have an effective dose or a therapeutically effective dose in the range 250 and 5000 TGPU per kg of the subject. [000448] In some embodiments, provided herein is a platelet derivative composition comprising platelet derivatives of any aspect provided herein, or a platelet derivative composition prepared by the process of any method for preparing or making provided herein, wherein the platelet derivatives comprise an imaging agent, to form imaging agent-loaded platelet derivatives. In some embodiments, the platelet derivatives in imaging agent-loaded platelet derivatives are freeze-dried platelet derivatives (FDPDs) that retain one, two, three, or more properties of FDPDs that are not loaded as described herein. In some embodiments, the imaging agent can be an MRI agent, such as gadolinium. In some embodiments, platelet derivatives comprise an MRI agent, termed as MRI agent-loaded platelet derivatives. In some embodiments, MRI agent-loaded platelet derivatives are freeze-dried platelet derivatives (FDPDs) that retain one, two, three, or more properties of FDPDs that are not loaded as described herein.

[000449] In some embodiments, provided herein is imaging agent-loaded platelets, cryopreserved platelets, or platelet derivatives. In some embodiments, provided herein is MRI agent-loaded platelets, cryopreserved platelets, or platelet derivatives. In some embodiments, imaging agent-loaded or MRI agent-loaded platelets, cryopreserved platelets, or platelet derivatives comprise a cell penetrating peptide (CPP). A CPP is coupled to an imaging agent or an MRI agent that facilitates the imaging agent or MRI agent to load onto platelets, cryopreserved platelets, or platelet derivatives. In illustrative embodiments, a CPP is a TAT peptide.

[000450] In some embodiments, provided herein is a method of delivering an imaging agent to a subject. In some embodiments, platelet derivatives or platelets as described herein are loaded with an imaging agent to form imaging agent-loaded platelet derivatives or platelets, such imaging agent-loaded platelet derivatives or platelets are administered to a subject. In some embodiments, platelet derivatives or platelets as described herein are loaded with an MRI agent to form MRI agent-loaded platelet derivatives or platelets, such MRI agent-loaded platelet derivatives or platelets are administered to a subject.

[000451] Also provided herein are compositions produced by any of the methods described herein. In some embodiments, any of the compositions provided herein can be made by the methods described herein. Specific embodiments disclosed herein may be further limited in the claims using “consisting of’ or “consisting essentially of’ language.

EXAMPLES

[000452] Example 1. Tangential Flow Filtration (TFF) Method of Platelet Derivative Preparation [000453] Apheresis platelets underwent tangential flow filtration in accordance with a standard operating procedure, including the following process steps: platelet dilution, platelet concentration and platelet washing.

[000454] The platelet donor units were initially pooled into a common vessel. The platelets may or may not be initially diluted with an acidified washing buffer (e.g., a control buffer) to reduce platelet activation during processing. The platelets can undergo two processing pathways; either washed with control buffer until a desired residual component is reached (e.g., donor plasma) before being concentrated to a final product concentration or the platelets are concentrated to a final product concentration before being washed with control buffer until a desired residual component is reached (e.g., donor plasma). In both the processing pathways, the platelet donor units were initially diluted or further diluted 1: 1 in Buffer A before being loaded onto a TFF machine for further processing. TFF processed platelets are then filled into vials, lyophilized and thermally treated.

[000455] One particular protocol follows.

[000456] For all steps of the TFF process in this Example, Buffer A was used. The process was carried out at a temperature of 18-24°C.

[000457] Buffer A

[000458] Platelets were initially diluted in Buffer A (1: 1) and loaded onto the TFF (PendoTECH controller system), which was prepared with a Repligen TFF Cassette (XPM45L01E). The TFF process was performed using a membrane with a pore size of 0.45 pm. The platelets were diluted with an equal weight (±10%) of Buffer A. The platelets were concentrated to about 2250 x 10³ cells/pL (±250 x 10³) and then washed with approximately 2 diavolumes (DV) of Buffer A. The target plasma percentage was typically less than 15% relative plasma (as determined by plasma protein content). Removal of plasma proteins was monitored through 280 nm UV absorbance against known correlations. Following washing, if the concentration of the cells was not 2000 x 10³ cells/pL (±300 x 10³), the cells were either diluted with Buffer A or were concentrated to fall within this range. Under all circumstances whenever the cells are contacted with the buffer A, it was done at a temperature in the range of 18-24°C. For a better clarity, the cells were loaded with the reagents of the buffer A at a temperature in the range of 18-24°C. The cells were typically then freeze-dried (lyophilized) and subsequently heated (thermally treated) at 80 °C for 24 hours, thereby forming thrombosomes, but sometimes the cells were used before lyophilization (sometimes called thrombosomes ‘pre-lyo’).

[000459] In order to perform studies related to the quantification of microparticles, quantification of expression or presence of various surface markers (like Annexin V, CD 41, CD 42, CD 47, CD 62, thrombospondin, von-Willebrand factor), thrombin generation studies (TGPU), aggregation studies, the thrombosomes were typically rehydrated with water over 10 minutes at room temperature. In general, the rehydration volume is equal to the volume used to fill each vial of thrombosomes prior to drying. The thrombosomes which were heated (thermally treated) after lyophilization are also referred to as baked thrombosomes. Whereas the thrombosomes which were not heated (thermally treated) after lyophilization are referred to as unbaked thrombosomes.

[000460] Platelet derivatives are also referred to herein as thrombosomes. In the following examples, the platelet derivatives/thrombosomes prepared in accordance with the procedure described in Example 1 is referred to as freeze-dried platelet derivative composition. The freeze-dried platelet derivative composition comprises freeze-dried platelet derivatives (also known as thrombosomes freeze- dried platelet derivatives). It would be clear to a skilled artisan that the thrombosomes which are obtained after lyophilization in the form of a powder can be used for commercial application, like providing the platelet derivative composition (thrombosomes) in dried form in vials to, for example, a medical practitioner who can rehydrate the vials with an appropriate amount of a liquid.

[000461] In some cases, samples were drawn at UV readings correlating to about 51% relative plasma volume, about 8.1% relative plasma volume, about 6.0% relative plasma volume, and about 1.3% relative plasma volume. Eow volume aliquots were sampled throughout each processing step with the about 6.0% and under samples.

[000462] Example 2. Testing Plan and Assay Protocol

[000463] Testing Plan: [000464] Freeze-dried platelet derivative composition Batch A was produced by the TFF method described in Example 1 using apheresis platelets collected from high-aHLA titer donors as reported by a platelet supplier.

[000465] Individual donor units, the donor pool, and timepoints along the TFF process were collected for aHLA testing. Plasma was added to HLA beads (One Lambda FLOWPRA™ Screen Test), stained with an algG secondary antibody, and evaluated for aHLA-IgG binding by flow cytometry (Novocyte 3005 configuration)

[000466] Two bead types were evaluated: one coated with HLA Class I antigens and the other coated with HLA Class II antigens. Bead gating was performed as described in the FLOWPRA™ Screen Test instructions. “aHLA Positive” populations are gated on the basis of a George King (GK) PPP (platelet-poor plasma) negative control and a single-donor fresh-drawn negative control. Additional negative controls are collected following production to confirm ideal placement of these positivity gates.

[000467] Compensation settings were established using FITC- and PE-conjugated mouse IgG on Spherotech COMPtrol compensation beads. The HLA Class II beads fluoresce in PE and the secondary antibody used for IgG detection is FITC-conjugated.

[000468] Assay Protocol:

1. Thaw the One Lambda FLOWPRA™ Screen Test kit components to 4°C.

2. Obtain approximately 1 mL aliquots of 0.2 pm filtered PPP from each desired sample point.

3. To a 1.7 mL microcentrifuge tube, pipet 5 pL Class I HLA beads and 5 pL Class II HLA beads. Add 20 pL filtered test plasma. Vortex to mix.

4. Incubate plasma with HLA-coated beads for 30 minutes at room temperature in the dark with gentle rocking/agitation.

5. Dilute lOx wash buffer to the appropriate volume of lx working stock with deionized water.

6. Wash the beads with 1 mL wash buffer. Vortex and centrifuge at 9,000 g x 2 minutes to pellet the beads. Aspirate the supernatant. 7. Repeat step 6.

8. Dilute lOOx algG-FITC to the appropriate volume of lx working stock with wash buffer.

9. Add 100 pL lx algG-FITC to the tube containing washed HLA beads. Vortex to mix.

10. Incubate HLA beads with algG-FITC for 30 minutes at room temperature in the dark with gentle rocking/agitation.

11. Repeat steps 6 and 7 to wash away unbound algG-FITC.

12. Resuspend the washed HLA beads in 200 pL PBS. Vortex to mix.

13. Pipet approximately 100 pL of the HLA bead suspension to the appropriate well(s) of a 96-well U-bottom microplate and dock onto the NovoSampler.

14. Use the NovoCyte to collect events by flow cytometry. a. Slow collection of 10,000 events in the previously determined FLOWPRA™ Beads gate with FSC-H threshold 10,000. b. Secondary stop conditions were 2 minutes run time and 40 pL total sample volume. c. The SIP is washed between each sample to minimize carryover between wells. A well of PBS is run between each triplicate set to minimize carryover between testing points.

[000469] Results

[000470] Example 3. Gate Placement and Negative Controls

[000471 ] Initial gate placement for identification of Class I and Class II HLA beads is determined using FLOWPRA™ beads in PBS. (Fig. 1A and Fig. IB)

[000472] Background/nonspecific binding is established using GK PPP and fresh donor PPP in triplicate. (Exemplary data is shown in Fig. 2A, Fig. 2B, Fig. 3A, and Fig 3B) Note that GK PPP is shifted higher on FITC-H than the fresh donor plasma. This may be due to donor variability or freeze/thaw effects on the GK plasma. Additional sampling is necessary. Positivity gates are placed such that <1% of GK PPP returns FITC-positive. [000473] Example 4. Single Donor Results

[000474] Representative FITC-H histograms from each HLA class are given for each sample.

Positivity >1% is positive. Fluorescence ratios are reported against the GK PPP negative control (Class I and Class II bead FITC-H intensity). Fluorescence ratios >1.0 are positive. As additional negative controls are collected these positivity gates and fluorescence ratios will be updated.

[000475] Populations are negative for HLA Class I or Class II antibodies if both percent positivity and fluorescence ratio are <1 forthat bead type.

[000476] Donor #1: HLA Class II Positive. Average positivity from triplicate data for Class I is 0.2% with fluorescence ratio 0.3; average positivity for Class II is 16.5% with fluorescence ratio 1.6. (Exemplary data is shown Fig. 4A and Fig. 4B).

[000477] Donor #2: HLA Class I and Class II Positive. Average positivity from triplicate data for Class I is 1.3% with fluorescence ratio 1.4; average positivity for Class II is 20.3% with fluorescence ratio 1.9. (Exemplary data is shown Fig. 5A and Fig. 5B).

[000478] Donor #3: HLA Class I and Class II Positive. Average positivity from triplicate data for Class I is 85.2% with fluorescence ratio 14.4. Average positivity for Class II is 12.0% with fluorescence ratio 0.8. (Exemplary data is shown Fig. 6A and Fig. 6B).

[000479] Donor #4: HLA Class I and Class II Positive. Average positivity from triplicate data for Class I is 83.5% with fluorescence ratio 14.5. Average positivity for Class II is 12.6% with fluorescence ratio 0.8. (Exemplary data is shown Fig. 7A and Fig. 7B).

[000480] Donor #5: HLA Class I and Class II Positive. Average positivity from triplicate data for Class I is 4.9% with fluorescence ratio 1.2. Average positivity for Class II is 1.3% with fluorescence ratio 0.8. (Exemplary data is shown Fig. 8A and Fig. 8B).

[000481] Donor #6: HLA Class I Positive. Average positivity from triplicate data for Class I is 2.7% with fluorescence ratio 0.9. Average positivity for Class II is 0.3% with fluorescence ratio 0.7. (Exemplary data is shown Fig. 9A and Fig. 9B).

[000482] Donor #7: HLA Class II Positive. Average positivity for from triplicate data Class I is 0.7% with fluorescence ratio 0.5. Average positivity for Class II is 9.0% with fluorescence ratio 1.3. (Exemplary data is shown Fig. 10A and Fig. 10B). [000483] The results for Donors 1-7 are also shown in Table 1.

[000484] Table 1.

[000485] Because there might be HLA-positive donors in the GK PNP pool, Table 2 displays results against an N=1 HLA-negative donor.

[000486] Table 2.

[000487] Example 5. Filtration Results

[000488] Pool: HLA Class I and Class II Positive. Average positivity from triplicate data for Class I is 61. 1% with fluorescence ratio 4.6. Average positivity for Class II is 9.0% with fluorescence ratio 1.1. (Exemplary data is shown Fig. 11A and Fig. 1 IB).

[000489] Initial Dilution (51%): HLA Class I and Class II Positive. Average positivity from triplicate data for Class I is 48.2% with fluorescence ratio 4.2. Average positivity for Class II is 5.9% with fluorescence ratio 0.9. (Exemplary data is shown Fig. 12A and Fig. 12B). [000490] “20%” Plasma (8.1%): HLA Class I Positive. Average positivity from triplicate data for

Class I is 2.4% with fluorescence ratio 1.0. Average positivity for Class II is 0.2% with fluorescence ratio 0.5. (Exemplary data is shown Fig. 13A and Fig. 13B).

[000491] “<10%” Plasma (6.0%): Borderline HLA Class I Positive. Average positivity from triplicate data for Class I is 1.1% with fluorescence ratio 1.0. Average positivity for Class II is 0.2% with fluorescence ratio 0.5. (Exemplary data is shown Fig. 14A and Fig. 14B).

[000492] “<3%” Plasma (1.3%): HLA Negative. Average positivity from triplicate data for Class

I is 0.4% with fluorescence ratio 0.2. Average positivity for Class II is 0.1% with fluorescence ratio 0.4. (Exemplary data is shown Fig. 15A and Fig. 15B).

[000493] The fdtration results are also shown in Tables 3A and 3B.

[000494] Table 3A.

[000495] Table 3B. Background fluorescence determined using HLA beads in PBS was subtracted from sample fluorescence prior to calculation of percent reduction in mean fluorescence intensity (a measure of reduction in antibody binding).

Values > 100% indicate complete reduction in detectable HLA antibody binding to the indicated beads.

[000496] Because there might be HLA-positive donors in the GK PNP pool, Table 4 displays results against an N=1 HLA-negative donor.

[000497] Table 4.

[000498] Example 6. Surface Markers and Thrombin Generation.

[000499] Freeze-dried platelet derivative composition batch were produced by the TFF method described in Example 1 and assayed for cell surface marker expression or presence or absence using flow cytometry. [000500] Flow cytometry was used to assess freeze-dried platelet derivative composition for expression or presence of CD41, CD62, and phosphatidylserine (PS). Samples included approximately 270,000/pL freeze-dried platelet derivatives during staining and were diluted approximately 1:34 before the sample was analyzed in the cytometer. Freeze-dried platelet derivative samples were rehydrated and diluted 1:2 in deionized water. A stock of anti-CD41 was diluted by adding 47.6 pL of antibody to 52.4 pL of HMTA. Samples stained with anti-CD41 were made by adding 10 pL of diluted freeze-dried platelet derivatives to 10 pL HMTA and 10 pL of diluted CD41 antibody. An anti-CD62 master mix was prepared by combining 12 pL anti-CD62 with 23.8 pL anti-CD41 and 64.2 pL of HMTA. An isotype control mix was made in the same manner. Samples stained with anti-CD62 were made by adding 10 pL of diluted freeze-dried platelet derivatives to 20 pL of the anti-CD62 master. The isotype master mix was used to make isotype control samples in the same manner. An annexin V (AV) master mix was prepared by combining 11.7 pL of AV with 83.3 pL of anti-CD41 and 80 pL of HMTA. Sample stained with AV were made by adding 20 pL of diluted freeze-dried platelet derivatives containing 50 mM GPRP to 20 pL of HMTA containing 15 mM CaCT and 20 pL of the AV master mix. Negative gating control samples were made in the same manner using HMTA without calcium to prevent AV binding to PS. All samples were incubated at room temperature for 20 minutes. After incubation 1 mL HBS was added to all samples. HBS used to dilute AV test samples contained 5 mM C’aCf Anti-CD41 binding was used to identify the population of interest. CD62 and PS expression or presence was assessed by anti-CD62 and AV binding within the CD41 positive population.

[000501] Glycoprotein lib (GPIIb, also known as antigen CD41) expression or presence was assayed using an anti-CD41 antibody (4.8 pL, Beckman Coulter part #IM1416U). The assayed freeze- dried platelet derivatives demonstrated CD41 positivity (Table 5; Fig. 16)

[000502] Table 5.

149

RECTIFIED SHEET (RULE 91 ) ISA/EP [000503] Phosphatidylserine (PS) expression or presence was assayed using annexin V (AV) (1.3 pL, BD Biosciences Cat. No. 550475). AV is a calcium-dependent phospholipid binding protein. The assayed freeze-dried platelet derivatives demonstrated AV positivity (Table 6; Fig. 17).

[000504] Table 6.

[000505] P-selectin (also called CD62P) expression or presence was assayed using an anti-CD62P antibody (2.4 pL, BD Biosciences Cat. No. 550888). The assayed freeze-dried platelet derivatives demonstrated CD62 positivity (Table 7, Fig. 18)

[000506] Table 7.

[000507] Thrombin generation was measured at 4.8xl0³ freeze-dried platelet derivatives/pl in the presence of PRP Reagent containing tissue factor and phospholipids using the below protocol. On average, the Thrombin Peak Height (TPH) for a freeze-dried platelet derivatives sample was 60.3 nM. Cephalin was used as a positive control. (Table 8; Fig. 19)

[000508] For each vial tested, a rehydrated sample of freeze-dried platelet derivatives was diluted to 7,200 particles per pL based on the flow cytometry particle count using 30% solution of Octaplas in control buffer. In a 96 well plate, sample wells were generated by adding 20 pL of PRP reagent (Diagnostica Stago Catalog No. 86196) and 80 pL of diluted freeze-dried platelet derivatives. Calibrator wells were generated by adding 20 pL of Thrombin Calibrator reagent (Diagnostica Stago Catalog No. 86197) to 80 pU of diluted freeze-dried platelet derivatives. The plate was loaded into the plate reader and incubated in the dark at 40°C for 10 minutes. During sample incubation, FluCa solution was prepared by adding 40 pL of FluCa substrate (Diagnostica Stago Catalog No. 86197) to 1.6 mb of Fluo-Buffer (Diagnostica Stago Catalog No. 86197) warmed to 37°C and vortexed to mix. The FluCa solution was aspirated in to the dispensing syringe and 20 pL was mechanically dispensed in to each reaction well, bringing the final freeze-dried platelet derivatives concentration in each well to 4,800 particles per pL and starting the thrombin generation reaction. Thrombin generation was measured via fluorescence in each well over the course of 75 minutes.

[000509] An exemplary step-by-step protocol follows:

1. Open CAT software; set up instrument; and prepare PRP reagent (including Tissue Factor and some phospholipids), calibrator, and fluo-buffer and fluo-substrate according to manufacturer guidelines.

2. Thaw Octaplas and TGA dilution buffer in 37 °C water bath for 10 minutes.

3. Add thawed Octaplas to TGA dilution buffer to create a buffer containing 30% Octaplas.

4. Use the 30% Octaplas mix to dilute reconstituted cephalin 1 :50 to be used as a positive control.

5. Rehydrate freeze-dried platelet derivative composition with cell culture grade water for 10 minutes then dilute with 30% Octaplas to 7,200 freeze-dried platelet derivatives/pL.

6. Using a multichannel pipette, add 20 pU of PRP reagent to each test well. Add 20 pU of Calibrator to each calibration well.

7. Add 80 pU of sample to each test and calibration well. Add 80 pU of 30% Octaplas to negative control wells and 1:50 cephalin to positive control wells.

8. Insert plate into tray and incubate for 10 minutes at 40° C. After incubation, dispense fluo-buffer and fluo-substrate mixture (including a fluorescent-labeled peptide, that when cleaved by thrombin, generates a fluorescent signal) into active wells.

9. Read plate for 75 minutes at 20 s intervals to capture full thrombin generation profile. Table 8.

[000510] Data from these assays is summarized in Table 9.

[000511] Table 9.

[000512] Example 7. 9F9 and PAC-1 binding.

[000513] Aggregation of activated platelets is mediated by the formation of the GPIIb/IIIa complex, which can bind to fibrinogen (also called Factor 1) and form a clot. GPIIb/IIIa is a platelet fibrinogen receptor also known as CD41/CD61 complex. In this process, ADP promotes the active form of the GPIIb/IIIa complex. Antibody 9F9 binds to fibrinogen associated with the cell membrane. The presence of fibrinogen on the cell membrane is thus indicative of freeze-dried platelet derivatives capable of forming clots.

[000514] A vial of freeze-dried platelet derivative composition prepared according to Example 1 was rehydrated using 10 m of deionized water. An aliquot of freeze-dried platelet derivatives was diluted to a final concentration of IxlO⁵ particles/pL using HMTA (HEPES Modified Tyrode’s Albumin). Samples were prepared as shown in Table 11. Unstained samples were prepared by adding 10 pL of diluted freeze-dried platelet derivatives to 20 pL of HMTA. FITC isotype control samples were prepared by adding 10 pL of diluted freeze-dried platelet derivatives to 10 pL of the isotype control antibody (BD Biosciences Cat. No. 555748) and 10 pL of HMTA. Samples stained with 9F9 were prepared by adding 10 pL of diluted freeze-dried platelet derivatives to 10 pL of the 9F9 antibody (BD Biosciences Cat. No. 340507 and 10 pL of HMTA. Samples stained with PAC-1 were prepared by adding 10 pL of diluted freeze-dried platelet derivatives to 5 pL of the isotype control antibody and 15 pL of HMTA. All samples were prepared in duplicated using a total of 1 x 10⁶ particles per reaction mixture. Samples were incubated at room temperature for 20 minutes away from open light. After incubation, all samples were diluted with ImL of HBS and analyzed using the ACEA NovoCyte flow cytometer. The fluorescent signal generated by PAC-1 was used to determine the expression or presence of activated GPIIb/IIIa receptors without bound fibrinogen. The fluorescent signal from 9F9 was used to determine binding of fibrinogen to the surface receptors on freeze-dried platelet derivatives.

[000515] HTMA (HEPES modified Tyrode’s albumin).

[000516] Table 10.

[000517] The samples were assayed by flow cytometry, and it was demonstrated that there is surface-bound fibrinogen post rehydration (Figs. 20), while the anti-PAC-1 antibody shows no significant binding (Figures 21). This is further evidence that the freeze-dried platelet derivatives prepared by TFF include fibrinogen bound to the active form of GPIIb/GPIIIa, as PAC-1 binds to the same complex.

[000518] Example 8. Evaluation of CD47 Binding

[000519] CD47 is a cell-surface marker used in self-recognition. Absence of this marker can, in some cases, lead to phagocytosis.

[000520] One vial of freeze-dried platelet derivative composition prepared as described in Example 1 was rehydrated with 10 m sterile water for injection and stained with increasing volumes of anti-CD47 antibody conjugated to Pacific Blue (BD Biosciences Cat. No. 561564) or a corresponding isotype control (BD Biosciences Cat. No. 560373). All samples contained 1 million cells. This titration resulted in a maximum fluorescent signal that was ~5x over background (Fig. 22A) and an overall CD47 positivity of ~40% (Table 12). An exemplary histogram is shown in Fig. 22B.

[000521] Aliquots of CD47 antibody conjugated to V450 were prepared at a 1: 10, 1:5, and 1:2 dilution with HMTA. The initial concentration of a freeze-dried platelet derivative sample was determined using the AcT diff 2 and the concentration of a 1 m aliquot was adjusted to 100 x 10³ per ph using HMTA. TFF freeze-dried platelet derivatives were stained in duplicate at each antibody dilution by adding 10 pL of antibody to 10 pF of diluted freeze-dried platelet derivatives. Samples stained with undiluted antibody were generated in the same manner. Unstained control samples were made by adding 10 ph of HMTA to 10 ph of diluted freeze-dried platelet derivatives. This sample preparation was repeated using an isotype control antibody in place of the anti-CD47. All samples were incubated at room temperature away from light for 20 minutes. After incubation samples were diluted with 500 ph of HBS and 15,000 events were acquired for each sample using the ACEA NovoCyte flow cytometer. V450 fluorescence in the test samples was used to assess antibody binding to CD47 on the freeze-dried platelet derivatives surface. V450 fluorescence of the isotype control samples was used to monitor nonspecific binding.

[000522] Table 11 shows the mean fluorescence intensity of samples with various amounts of antibody (anti-CD47 or isotype control).

[000523] Table 11.

[000524] Table 12 shows the CD47 percent positivity at various concentrations of anti-CD47 antibody.

[000525] Table 12.

[000526] A second vial of TFF freeze-dried platelet derivatives from a different lot was rehydrated and stained with increasing volumes of anti-CD47 conjugated to Pacific Blue or a corresponding isotype control. All sampled contained 250,000 cells. Again, fluorescent signal that was ~5x to 6x over background (Figure 22C) and an overall CD47 positivity of -50% (Table 15). An exemplary histogram is shown in Figure 22D.

[000527] A second round of testing was performed on a new TFF freeze-dried platelet derivatives sample using an increased amount of antibody and decreased number of freeze-dried platelet derivatives per sample in order to improve the intensity of the signal caused by anti-CD47 binding to the freeze-dried platelet derivatives. The initial concentration of a freeze-dried platelet derivatives sample was determined using the AcT diff 2 and the concentration of a 1 mb aliquot was adjusted to 25 x 10³ per pL using HMTA. Samples were stained in duplicate with increasing amounts of antibody according to Table 13 below. The final volume for each sample was held constant at 40 pL. The total number of freeze-dried platelet derivatives in each sample was help constant at 250 x 10³ per pL. This sample preparation was repeated using an isotype control antibody in place of the anti-CD47.

[000528] Table 13.

[000529] All samples were incubated at room temperature away from light for 20 minutes. After incubation samples were diluted with 500 pL of HBS 15,000 events were acquired for each sample using the ACEA NovoCyte flow cytometer. V450 fluorescence in the test samples was used to assess antibody binding to CD47 on the freeze-dried platelet derivatives surface. V450 fluorescence of the isotype control samples was used to monitor nonspecific binding.

[000530] Table 14 shows the mean fluorescence intensity of samples with various amounts of antibody (anti-CD47 or isotype control).

[000531] Table 14.

[000532] Table 15 shows the CD47 percent positivity at various concentrations of anti-CD47 antibody.

[000533] Table 15.

[000534] Example 9. Microparticle Content Reduction

[000535] The microparticle content of human in-date stored platelets (hIDSP) compared to freeze- dried platelet derivative composition prepared according to Example 1 (but not lyophilized) were compared using dynamic light scattering. The results are shown in Figures 23A-C and Table 16. Figures 23A-C are histograms that are normalized to a relative intensity so that the sum of the intensity of each data point equals 1.0. For example, if a particular data point has a y-axis value of 0. 1 then it can be typically interpreted that the data point makes up 10% of the scattering intensity of the sample.

[000536] A pool of the apheresis units used to manufacture a batch of freeze-dried platelet derivative composition was made for analysis. This sample type is denoted as “hIDSP.” A ImL aliquot of this hIDSP (human In-Date Stored Platelets) pool was taken for dynamic light scattering (DLS; Thrombolux - Light Integra) analysis. A sample from this aliquot was then drawn into a capillary and inserted into the DLS instrument. The capillary sat in the instrument for 1 minute to allow the temperature and movement to equilibrate. The internal temperature of the machine is 37°C. After 1 minute of equilibration, the viscosity setting for the sample was chosen. The DLS instrument has a built-in viscosity setting for samples that are in plasma, such as apheresis units. This viscosity setting was used for hIDSP samples. The viscosity of this setting is 1.060cP (centipoise). After the plasma viscosity setting was selected, the sample was analyzed. From the same hIDSP aliquot, a 2^nd and 3^rd sample were drawn into a capillary and analyzed with this hIDSP protocol, for triplicate analysis. Microparticle percentage was then determined from the data.

[000537] “Pre-Lyo” samples are an in-process sample from the freeze-dried platelet derivatives manufacturing process. This sample type is the material taken right before lyophilization. A viscosity measurement of the sample was taken in order to analysis these samples with DLS. The viscometer (Rheosense pVISC) has a built-in oven that is used to bring the sample to the temperature of the DLS instrument (37°C). Prior to viscosity analysis of the sample the oven must be heated to 37°C. To determine the viscosity of the pre-lyo sample a 400-350pL sample was drawn into a syringe and inserted into the viscometer. After inserting the sample into the viscometer, the instrument temperature needs to reach 37°C again. After the oven reaches 37°C the sample was analyzed with all settings on AUTO except for “Measurement Volume” which was set to 400pL. This viscosity was used for the DLS measurement of the same sample. A ImL aliquot of this pre-lyo sample was taken for dynamic light scattering (DLS; Thrombolux - Lightlntegra) analysis. A sample from this aliquot was then drawn into a capillary and inserted into the DLS instrument. The capillary sat in the instrument for 1 minute to allow the temperature and movement to equilibrate. The internal temperature of the machine is 37°C. After 1 minute of equilibration, the previously measured viscosity was put into the viscosity setting of the DLS instrument. After the viscosity was entered, the sample was analyzed. From the same pre-lyo aliquot, a 2^nd and 3^rd sample were drawn into a capillary and analyzed with this Pre-Lyo Protocol, for triplicate analysis. Microparticle percentage was then determined from the data.

[000538] Freeze-dried platelet derivatives were rehydrated according to standard protocol and diluted 1:5 in a mixture of SeraSub (CST Technologies, Inc.) and ACD. The SeraSub/ACD diluent consists of a 1:9 dilution of ACD in SeraSub. ImL of the 1:5 dilution of freeze-dried platelet derivatives was prepared for analysis by DLS. A sample of the freeze-dried platelet derivatives dilution was drawn into the capillary and inserted into the DLS instrument. The capillary sat in the instrument for 1 minute to allow the temperature and movement to equilibrate. The internal temperature of the machine is 37°C. After 1 minute of equilibration, the viscosity setting for the sample was chosen. The viscosity used for the sample was 1.200cP. After the viscosity was entered, the sample was analyzed. A 2^nd, 3^rd, and 4^th sample were drawn into a capillary and analyzed with this freeze-dried platelet derivatives protocol, for quadruplicate analysis. Microparticle percentage was then determined from the data (and platelet radius where applicable).

[000539] Table 16.

[000540] In additional experiments, the microparticle content of human in-date stored platelets (hIDSP) compared to rehydrated freeze-dried platelet derivatives prepared according to Example 1 were compared using dynamic light scattering (DLS). The results are shown in Figures 24A-C and Table 17.

[000541] Table 17.

[000542] Example 10. Metabolite Analysis

[000543] Table 18 shows an analysis of pH and metabolites present in the preparation of freeze- dried platelet derivative composition as described in Example 1, including analyses of the raw platelet material, after an initial dilution, after the platelet derivatives were concentrated, and after the end of the diafiltration process, as determined using an i-STAT handheld blood analyzer and CG4+ cartridges.

[000544] Platelet samples for iStat analysis were collected at different processing steps in small volumes (1ml). The initial sample for iStat analysis named “Raw Material” was collected after the platelet donor units were pooled together but before any processing had occurred. Named “Initial Dilution”, The pooled platelet units were 1 : 1 diluted with Control Buffer before subjecting the platelets to TFF processing. At the end of the concentration phase of TFF, the “End of Cone” sample was drawn from the platelet product. After washing the cells, the “End of DV (Pre-Lyo)” sample was drawn as a representation of the product as it enters the lyophilizer.

[000545] Table 18.

[000546] Example 11. Pathogen Reduction

[000547] The reduction of pathogens is generally desirable in blood products. One method of pathogen reduction involves the use of a photosensitive nucleic acid-intercalating compound to alter the nucleic acids of pathogens upon illumination with an appropriate wavelength.

[000548] The INTERCEPT® system (made by Cerus) uses amotosalen, a nucleic acid intercalating compound that forms cross-links in nucleic acid upon illumination with UVA. Exemplary parameters for use of this system are shown in Table 19, and a schematic of the system is shown in Fig. 25 A, while exemplary process data are shown in Figs. 25B-C for 2.6L of processed material in 198 minutes (approx. 14/min average).

[000549] DLS was performed as described in Example 9.

[000550] Table 19.

[000551 ] Exemplary comparative data of pH and metabolites of freeze-dried platelet derivative composition prepared as in Example 1, with or without treatment with the INTERCEPT® system is shown in Table 20.

[000552] Table 20.

[000553] Exemplary comparative data of functional characterization (AcT count and aggregation parameters) and cell-surface markers are shown in Tables 21 (hIDSPs), 22 (prior to lyophilization) and Table 23 (following lyophilization and rehydration in 10 m sterile water for injection to a concentration of approximately 1.8xlO⁶/pL (individual sample counts are shown in Table 23).

[000554] Table 21.

[000555] Table 22.

[000556] Table 23.

[000557] The microparticle content at various stages of the preparation of freeze-dried platelet derivatives was also determined as described in Example 9. Figs. 26A-B show the similarity of rehydrated freeze-dried platelet derivatives prepared with and without pathogen reduction treatment. A summary of these data is shown in Table 24. Fig. 27A shows the microparticle content of hiDSPs with or without pathogen reduction treatment. Figs. 27B-C compare the microparticle content of the hiDSPs shown in Fig. 29A and rehydrated freeze-dried platelet derivatives prepared therefrom. A summary of these data is shown in Table 25. Fig. 28A shows the microparticle content of hiDSPs with or without pathogen reduction treatment. Figs. 28B-C compare the microparticle content of the hiDSPs shown in Fig. 28A and rehydrated freeze-dried platelet derivatives prepared therefrom. A summary of these data is shown in Table 26. [000558] Table 24.

[000559] Table 25.

[000560] Table 26.

[000561] Example 12. Interactions between Platelets and freeze-dried platelet derivatives.

[000562] In this Example, ‘platelets’ are platelets isolated from citrated whole blood approximately 3 hours post-collection. The freeze-dried platelet derivatives are Batch D, prepared by the method described in Example 1. Table 27 is a sample layout for the experiments in this Example.

[000563] Table 27.

[000564] Platelet and freeze-dried platelet derivatives co-aggregation was evaluated by light transmission aggregometry. Platelets and freeze-dried platelet derivatives were coincubated and evaluated by aggregometry +/- platelet activation with 4f)-Phorbol-l 2-myristatc-l 3-acctatc (PMA). For fresh-drawn platelets isolated from whole blood, 100 ng/mL PMA was used. For stored platelets (i.e. apheresis platelets) 1000 ng/mL PMA was used.

164

RECTIFIED SHEET (RULE 91 ) ISA/EP [000565] Fresh platelets were isolated from ACD anticoagulated whole blood, washed, and diluted to 250,000 cells/pL in HMTA. Freeze-dried platelet derivatives were rehydrated according to standard protocol and diluted to 250,000 cclIs/uL in HMTA. An aliquot each of platelets in HMTA and freeze- dried platelet derivatives in HMTA were mixed in equal proportions. Platelets, freeze-dried platelet derivatives, and the mixed sample were evaluated by light transmission aggregometry (Helena AggRAM) in response to phorbol-myristate-acetate (PMA; 100 ng/mL) activation. The mixed samples were evaluated with and without a stir bar to assess the effect of stirring-induced shear on observed platelet- Freeze-dried platelet derivatives coaggregation.

[000566] FIG. 29A shows the transmittance of the samples in Table 30, with and without agonist. Plus shear and minus agonist (black) mixing, freeze-dried platelet derivatives and fresh-drawn platelets induced platelet activation and aggregation. PMA (gray) activated platelets and the magnitude of % transmittance suggests mixed aggregation with freeze-dried platelet derivatives. Without shear there is either no activation or co-aggregation to less than the magnitude observed in FIG. 29A.

[000567] The platelet and freeze-dried platelet derivatives AcT counts pre- and post-aggregometry were also evaluated. FIG. 29B shows the post-aggregation counts. Cases for which the white bar is greater than the other(s) suggest incorporation of freeze-dried platelet derivatives into platelet aggregates. The absolute decrease in particle count for the no agonist cases (black) is especially dramatic and unexpected.

[000568] The effect of shear on aggregation was also evaluated. Mixed aggregometry (1:1 platelets: freeze-dried platelet derivatives by count) was repeated with and without stir bars. Results are shown in Figure 29C. These results show that shear is necessary for observable coaggregation in the absence of a platelet agonist. The magnitude of measured counts and co-aggregation +/- agonist is slightly decreased in plasma vs buffer.

[000569] Example 13. Inhibition of Fibrin Trapping with GPRP.

[000570] In this Example, ‘platelets’ are isolated from whole blood approximately 1 hour postcollection. The freeze-dried platelet derivatives are Batch H, prepared by the method described in Example 1.

[000571] Fresh platelets were isolated from ACD anticoagulated whole blood, washed, and diluted to 250,000 cells/pL in HMTA. Freeze-dried platelet derivatives were rehydrated according to standard protocol and diluted to 250,000 cclIs/uL in HMTA. An aliquot each of platelets in HMTA and freeze-

165

RECTIFIED SHEET (RULE 91 ) ISA/EP dried platelet derivatives in HMTA were mixed in equal proportions. Each group of platelets, freeze-dried platelet derivatives, or mixed suspensions were divided equally; one group was treated with 1 mM GPRP to inhibit fibrin polymerization and one group remained untreated. The peptide Gly-Pro-Arg-Pro (GPRP; Sigma- Aldrich item G1895) is a peptide that prevents fibrin polymerization. Platelets, freeze-dried platelet derivatives, and the mixed samples were evaluated by light transmission aggregometry (Helena AggRAM) in response to thrombin (2.5 U/mL) activation.

[000572] Figure 30 shows the results of co-aggregation experiments using platelets, freeze-dried platelet derivatives, and 2: 1 and 1: 1 mixtures of platelets and freeze-dried platelet derivatives, all activated with thrombin, either in the presence or absence of GPRP (1 mM). In the mixed cases, total measured aggregation decreased as the freeze-dried platelet derivatives population increased, suggesting that the interaction of platelets and freeze-dried platelet derivatives is partly caused by fibrin trapping. However, the bulk of the co-aggregation interaction was platelet-mediated, and not reliant on fibrin trapping as evidenced by high measured aggregation even with GPRP.

[000573] Examples 12-13 show that platelets and freeze-dried platelet derivatives co-aggregated under shear with (and to a lesser extent, without) platelet activation. The fibrin polymerization inhibitor GPRP only slightly inhibited platelet-freeze-dried platelet derivatives co-aggregation following thrombin activation.

[000574] Example 14. RGDS Inhibition of Co-aggregation.

[000575] In this Example, ‘platelets’ are isolated from whole blood approximately 1 hour postcollection. The freeze-dried platelet derivatives are Batch H, prepared by the method described in Example 1.

[000576] Fresh platelets were isolated from ACD anticoagulated whole blood, washed, and diluted to 250,000 cells/pL in HMTA. Freeze-dried platelet derivatives were rehydrated according to standard protocol and diluted to 250,000 cells/pL in HMTA. An aliquot each of platelets in HMTA and freeze- dried platelet derivatives in HMTA were mixed in equal proportions. Each group of platelets, freeze-dried platelet derivatives, or mixed suspensions were divided equally; one group was treated with 100 pM RGDS to inhibit fibrinogen binding to platelets and one group remained untreated. RGDS (Arg-Gly-Asp- Ser; Cayman Chemical item 15359) is a peptide sequence that binds platelet surface integrins, particularly GPIIb/IIIa. It inhibits platelet binding to fibrinogen and other adhesive proteins. Platelets, freeze-dried platelet derivatives, and the mixed samples were evaluated by light transmission aggregometry in response to phorbol myristate-acetate (PMA; 100 ng/mL) activation.

[000577] Co-aggregation experiments were performed with 100 pM RGDS and activation with PMA to investigate whether the interaction is caused by fibrinogen bridging between platelets and freeze- dried platelet derivatives. Results are shown in Fig. 31. RGDS blocks >50% of measured co-aggregation, suggesting the interaction between platelets and freeze-dried platelet derivatives may be caused in a large part by fibrinogen binding.

[000578] Examples 12-14 show that freeze-dried platelet derivatives readily co-aggregate with activated platelets (e.g., as evidenced by light transmission aggregometry). Spontaneous co-aggregation is induced by shear. Platelet-freeze-dried platelet derivatives interactions are apparent in both buffer and plasma. While co-aggregation is not substantially inhibited by GPRP, co-aggregation is substantially inhibited by RGDS. This suggests a key role for active platelet-fibrinogen binding in the co-aggregation mechanism and that co-aggregation is not caused only by passive fibrin trapping.

[000579] Example 15. Scanning Electron Microscopy (SEM).

[000580] A 10 m aliquot of rehydrated freeze-dried platelet derivatives were centrifuged at 2000 RPM for 30 minutes. The supernatant of the centrifuges sample was removed down to 1 m and discarded. The sample was gently agitated to resuspend the freeze-dried platelet derivatives. The concentrated freeze-dried platelet derivatives were treated with 3% glutaraldehyde in 0.1 M cacodylate buffer at a pH of 7.4 for 2 hours with agitation every 15 minutes. The freeze-dried platelet derivatives were rinsed with sterile water three times and transferred to a 1% solution of osmium tetroxide for 1 hour with agitation every 15 minutes. The sample was then rinsed three more times with sterile water and a 0.5 mb droplet was transferred to a polysulfone filter membrane. The mounted sample was frozen with liquid nitrogen and dried under vacuum before being gold sputtered and imaged using scanning electron microscopy.

[000581] Figs. 32A-D show SEM of platelets and human freeze-dried platelet derivatives. Fresh activated platelets are shown in Fig. 32A (scale bar = 2 pm) and Fig. 32B (scale bar = 1 pm). Rehydrated human freeze-dried platelet derivatives prepared as in Example 1 are shown in Fig. 32C (scale bar = 2 pm) and Fig. 32D (scale bar = 1 pm).

[000582] Example 16. T-TAS® Freeze-dried platelet derivatives Data. [000583] In the Total Thrombus-formation Analysis System (T-TAS®, FUJIMORI KOGYO CO., LTD), the sample is forced through collagen-coated microchannels using mineral oil. Changes in pressure are used to assess thrombus formation. The Occlusion Start Time is time it takes to reach A10 kPa, and the Occlusion Time = time it takes to each A80 kPa using an AR chip (Zacros Item No, TC0101).

[000584] According to FUJIMORI KOGYO CO., LTD, an AR chip can be used for analyzing the formation of a mixed white thrombus consisting chiefly of fibrin and activated platelets. It has a flow path (300 pm wide by 50 pm high) coated with collagen and tissue factors and can be used to analyze the clotting function and platelet function. In comparison, a PL chip can be used for analyzing the formation of a platelet thrombus consisting chiefly of activated platelets. A PL chip has a flow path coated with collagen only and can be used to analyze the platelet function.

[000585] T-TAS® reagents (CaCTI, AR Chip) were warmed to 37°C and freeze-dried platelet derivatives were rehydrated according to standard protocol. An aliquot of the rehydrated freeze-dried platelet derivatives was washed by centrifugation at 3900 g x 10 minutes and resuspended to approximately 300,000 cells/pL in sodium citrate anticoagulated platelet-poor plasma (PPP). CaCTI (20 pL) was mixed with freeze-dried platelet derivatives in PPP (480 pL) and run through the T-TAS AR Chip under high shear. Pressure in the system was monitored over 30 minutes or until the maximum backpressure in the channel was achieved.

[000586] The T-TAS® instrument was prepared for use according to the manufacturer's instructions. AR Chips (Diapharma Cat. # TC0101) and AR Chip Calcium Com Trypsin Inhibitor (CaCTI; Diapharma Cat. # TRO 101) were warmed to room temperature. 300 pL of rehydrated freeze- dried platelet derivatives were transferred to a 1.7 mL microcentrifuge tube and centrifuged at 3900 g x 10 minutes to pellet. The freeze-dried platelet derivatives pellet was resuspended in George King (GK) pooled normal human plasma or autologous plasma with or without autologous platelets to a concentration of approximately 100,000-450,000/pL, as determined by AcT counts (Beckman Coulter AcT Diff 2 Cell Counter). 20 pL of CaCTI with 480 pL of freeze-dried platelet derivatives sample in GK plasma were mixed with gentle pipetting. The sample was loaded and run on the T-TAS® according to the manufacturer's instructions.

[000587] Table 28 shows T-TAS® results from citrated whole blood, platelet-reduced citrated whole blood supplemented with varying concentrations of freeze-dried platelet derivatives as prepared in Example 1, and George King Platelet Poor Plasma (GK PPP) supplemented with varying concentrations of freeze-dried platelet derivatives as prepared in Example 1 in experiments run according to the manufacturer’s instructions using the AR chip and High Shear instrument settings.

[000588] Table 28.

T-TAS AR Chip Results

*Test peaked at ~75kPa before rapidly dropping off. Possible erroneous result. Test timed out.

[000589] Time-elapsed results are shown in Figures 33A-B. Increasing the concentration of freeze- dried platelet derivatives in platelet-reduced whole blood promoted more robust thrombus formation as measured by shortened occlusion times (Fig. 33A). Increasing the concentration of freeze-dried platelet derivatives in platelet poor plasma (PPP) promoted more robust thrombus formation as measured by shortened occlusion times (Fig. 33B).

[000590] The effect of GPRP (1 mM) on occlusion activity was also assayed. Table 29 shows T- TAS® results for platelet-poor plasma, with and without freeze-dried platelet derivatives in the presence and absence of GPRP. Adding GPRP to prevent fibrinogen formation did not prevent the freeze-dried platelet derivatives -containing sample from reaching occlusion pressure. While the addition of GPRP to freeze-dried platelet derivatives samples in plasma prevents the formation of fibrin in the microcapillary channel (Figs. 33C (no GPRP) and 33D (GPRP), both in GK PPP), the addition of GPRP to freeze-dried platelet derivatives (PPP) did not prevent thrombus formation (Fig. 33E).

[000591] Table 29.

"Test timed out

[000592] Example 17. Inability of freeze-dried platelet derivatives to aggregate in the presence of agonists and absence of fresh platelets

[000593] Light transmission aggregometry (LTA) was used to observe freeze-dried platelet derivatives aggregation in the presence of known platelet aggregation agonists. The freeze-dried platelet derivatives aggregation data was compared to aggregation data of fresh platelets.

[000594] Freeze-dried platelet derivatives, also referred as “TFF thrombosomes”, were produced by the TFF method described in Example 1. Fresh platelets in Platelet Rich Plasma (PRP) were prepared from whole blood collected in acid-citrate-dextrose (ACD) collection tubes (BD Vacutainer ACD Solution A Blood Collection Tubes ref# 364606). Platelet rich plasma (PRP) was prepared by centrifugation of ACD- whole-blood at 180g for 15 minutes at 22°C using a Beckman Coulter Avanti J-15R centrifuge. Platelet poor plasma (PPP) was prepared by centrifugation of ACD-whole-blood at 2000g for 20 minutes at 22°C. [000595] For sample preparation for aggregometry studies, PRP was diluted with PPP to a platelet concentration (pit count) of 250,000 plts/uL. Platelet count was determined using a Coulter Ac«T diff2 Hematology Analyzer.

[000596] Freeze-dried platelet derivatives, lyophilized and thermally treated, were prepared using tangential flow filtration (TFF) as described in Example 1. A 30mL vial of freeze-dried platelet derivatives was rehydrated using 30 mL of cell culture grade water (Coming Cat# 25-055-CI). The vial was incubated at room temperature for a total of 10 minutes. During the 10-minute rehydration period, the vial was gently swirled at 0, 5, and 10 minutes to promote dissolution of the lyophilizate. The aggregometry studies as per the present Example was carried out in the absence of fresh platelets. Therefore, the aggregometry studies supported only aggregation ability of the freeze-dried platelet derivatives, but not the co-aggregation ability. [000597] For sample preparation for aggregometry studies, rehydrated freeze-dried platelet derivatives were diluted in a buffer to a platelet count of 250,000/pL. Freeze-dried platelet derivatives sample preparations used for ristocetin aggregation studies were composed of 20% citrated plasma (George King Bio-Medical, Inc. Pooled Normal Plasma product# 0010-1) and buffer.

[000598] Light transmission aggregometry (LTA) (Bio/Data PAP-8E Platelet Aggregometer catalog# 106075) at 37°C was used to observe the aggregation response of freeze-dried platelet derivatives (Fig. 34A) and PRP samples (Fig. 34B) from a final concentration of 20 pM ADP, 10 pg/mL collagen, 200 pM epinephrine (ADP, collagen, and epinephrine reagents from Helena Laboratories Platelet Aggregation Kit cat. # 5369), 0.5 mg/mL arachidonic acid (Helena Arachidonic Acid Reagent cat.), Img/mL ristocetin (Helena Ristocetin for Aggregation Assays cat.), and 10 pM thrombin receptor activator peptide 6 (TRAP- 6) (Sigma Aldrich Cat# T1573-5MG). PPP, buffer, or buffer with 20% citrated plasma were used as blanks for the PRP, freeze-dried platelet derivatives, and freeze-dried platelet derivatives with 20% citrated plasma samples, respectively. Prior to agonist treatment, 225 pL of freeze-dried platelet derivatives or PRP sample was reverse pipetted in a test tube containing a stir bar. The test tube was then placed into the aggregometer’s non-stirred incubation well for 1 minute. The sample was then placed into a stirred incubation well for 1 minute. The sample was then placed into the stirred test well and the aggregation test was initiated. After 1 -minute of baseline observation the sample was treated with agonist and the aggregation response was recorded. Using the same procedure as the test runs, a negative control of 25 pL buffer was included simultaneously with all runs to determine spontaneous baseline-aggregation responses of all sample groups.

[000599] Freeze-dried platelet derivative composition in 1.7 mL microcentrifuge tubes, at room temperature, were treated with an agonist at a final agonist concentration of 20 pM ADP, 0.5 mg/mL arachidonic acid, 10 pg/mL collagen, 200 pM epinephrine, Img/mL ristocetin, and 10 pM TRAP-6 or 25 pL buffer. Freeze-dried platelet derivative counts were determined prior to and 5 -minutes after agonist treatment.

[000600] ADP (Fig. 34C), collagen (Fig. 34D), epinephrine (Fig. 34E), ristocetin (Fig. 34F), and TRAP-6 (Fig. 34G) did not cause an aggregation response in freeze-dried platelet derivatives when measured by LTA. Freeze-dried platelet derivatives’ response from the aforementioned agonists was equivalent to baseline aggregation values that would be obtained from no agonist or a negative control of buffer. When freeze-dried platelet derivatives were treated with arachidonic acid (AA) and observed by LTA (Fig. 34H) there was an apparent aggregation response, however after visual inspection of the aggregometry cuvette it was observed that the solution had become visibly clear and aggregates were not observed, indicating that the apparent aggregation response was from lysis of freeze-dried platelet derivatives and not AA induced aggregation. Determining aggregation by cell count for freeze-dried platelet derivatives produced similar results to the LTA results for all agonists.

[000601] Agonists’ functionality was confirmed by performing LTA on fresh PRP (Fig. 34B). ADP, arachidonic acid, collagen, epinephrine, ristocetin and TRAP-6 caused normal aggregation profiles and magnitudes that are representative of a strong aggregation response in PRP. The aggregation response from epinephrine in PRP was reduced, however epinephrine was still able to elicit an aggregation response that was above baseline aggregation. The negative control of buffer in PRP indicated that the PRP was not activated prior to agonists additions. Visual inspection of the PRP samples after the aggregation tests indicated that no cell lysis had occurred and platelet aggregates were visually observed in the aggregation cuvettes for all agonists, indicating that all aggregations responses were from platelet aggregation. The aggregation percentage of freeze-dried platelet derivatives and fresh PRP observed in the presence of the afore -mentioned agonists have been captured in Table 30.

[000602] Table 30

* - Due to lysis of freeze-dried platelet derivatives and not aggregation

[000603] Example 18. Freeze-dried platelet derivatives are maximally activated - Binding of Annexin V to freeze-dried platelet derivatives in the presence of TRAP

[000604] Freeze-dried platelet derivatives, prepared using the TFF process as described on Example 1 and treated with TRAP-6, were tested for the presence of phosphatidylserine (PS), indicative of an activated platelet, on the surface of the freeze-dried platelet derivatives. The presence of PS was assessed by analysis of Annexin V (AV) binding to the freeze-dried platelet derivatives.

[000605] One 30 m vial of freeze-dried platelet derivatives composition prepared using the TFF process as described in the Example 1 was rehydrated using 30 m of cell culture grade water (Coming Cat# 25 -055 -CI). After water was added to the vial, the vial was incubated for 10 minutes at room temperature. Gentle swirling of the vial was performed every 2 minutes during the 10-minute period to promote full dissolution of the cake. Once the freeze-dried platelet derivatives were fully rehydrated, two 475 pL aliquots were transferred to two separate 1.7 m microcentrifuge tubes. Twenty-five microliters of HEPES Modified Tryode’s Albumin buffer (HMTA) (Cellphire RGT-004) was added to the sample in the first tube to generate freeze-dried platelet derivatives without TRAP-6. Twenty-five microliters of 400 pM Thrombin Receptor Activating Peptide 6 (TRAP-6) (Sigma Aldrich Cat# T1573-5MG) was added to the second tube to generate freeze-dried platelet derivatives with TRAP-6. The final concentration of TRAP-6 during incubation was 20 pM. Both tubes were inverted 5 times to mix and incubated at room temperature for 10 minutes.

[000606] After incubation with HMTA buffer or TRAP-6, the samples were further diluted 1:20 by adding 10 pL of the freeze-dried platelet derivatives sample to 190 pL HMTA. These diluted samples of freeze-dried platelet derivatives incubated with HMTA and freeze-dried platelet derivatives incubated with TRAP-6 were both stained in 1.7 mb microcentrifuge tubes as follows: unstained control samples were generated by combining 10 pL of freeze-dried platelet derivatives and 20 pL HMTA; calcium free control samples were generated by combining 10 pL of freeze-dried platelet derivatives, 5 pL of Annexin V - ACP (BD Pharmingen Cat# 550475), and 15 pL HMTA; Annexin V (AV) stained test samples were generated by combining 10 pL of freeze-dried platelet derivatives, 5 pL of AV - ACP ,and 15 pL HMTA supplemented with 9 mM CaC12 (Cellphire RGT-012 Lot# LAB-0047-21). The final concentration of CaC’E in the AV-stained test samples was 3 mM. All stained samples for both freeze-dried platelet derivatives incubated with HMTA and freeze-dried platelet derivatives incubated with TRAP-6 were generated in triplicate. The samples were incubated at room temperature, protected from light, for 20 minutes.

[000607] After incubation, 500 pL ofHEPES buffered saline (HBS) (Cellphire RGT-017) was added to all unstained control and calcium free control samples. Five hundred microliters of HBS supplemented with 3 mM CaC12 was added to the AV-stained test samples. One hundred microliters from each sample was transferred to an individual well in a 96 well plate, and the samples were analyzed using an Agilent Quanteon flow cytometer.

[000608] TRAP-6 activity was confirmed by measuring CD62P expression in human apheresis platelets with and without exposure to TRAP-6. Two 475 pL aliquots of apheresis platelets were transferred to two separate 1.7 mb microcentrifuge tubes. Twenty-five microliters of HMTA buffer was added to the sample in the first tube to generate apheresis platelets without TRAP-6. Twenty-five microliters of 400 pM TRAP-6 was added to the second tube to generate freeze-dried platelet derivatives with TRAP-6. The final concentration of TRAP-6 during incubation was 20 pM. Both tubes were inverted 5 times to mix and incubated at room temperature for 10 minutes.

[000609] After incubation with HMTA buffer or TRAP-6, the samples were further diluted 1:20 by adding 10 pL of apheresis platelets to 190 pL HMTA. These diluted samples of apheresis platelets incubated with HMTA and apheresis platelets incubated with TRAP-6 were both stained in 1.7 mb microcentrifuge tubes as follows: unstained control samples were generated by combining 10 pL of apheresis platelets and 20 pL HMTA; Anti-CD62P stained test samples were generated by combining 10 pL of apheresis platelets, 5 pL of anti-CD62P-PE antibody (BD Pharmingen Cat# 550561 Lot# 6322976), and 15 pL HMTA. All stained samples for both apheresis platelets incubated with HMTA and apheresis platelets incubated with TRAP-6 were generated in triplicate. The samples were incubated at room temperature, protected from light, for 20 minutes.

[000610] After incubation, 500 pL of phosphate buffered saline (PBS) (Coming Cat# 21-040-CV1) was added to all samples. One hundred microliters from each sample was transferred to an individual well in a 96 well plate, and the samples were analyzed using an Agilent Quanteon flow cytometer.

[000611 ] Freeze-dried platelet derivatives manufactured using the TFF process were incubated with either TRAP-6 or buffer and stained with Annexin V (AV) to determine the relative presence of phosphatidylserine (PS). Apheresis platelets were used to confirm TRAP-6 activity (Fig. 35A, and Table 31), and increased expression of CD62P after the exposure to TRAP-6 confirms that TRAP-6 is capable of promoting platelet expression. PS expression on the exterior membrane leaflet is a hallmark of platelet activation and increases in membrane expression of PS result in greater amounts of AV binding. Unstained samples and samples stained with AV but without the addition of calcium were analyzed on the flow cytometer as negative controls. Unstained samples generated little to no fluorescent signal, indicating that freeze-dried platelet derivatives were not auto fluorescent at the wavelength selected to measure AV (Fig. 35B). The calcium free control samples also generated little to no fluorescent signal. Since AV binding to PS is dependent on the presence of calcium ions, a lack of signal from the calcium free control samples demonstrates that the AV-ACP conjugate was not associating with the freeze-dried platelet derivatives membrane in a nonspecific manner. All samples stained with AV in the presence of calcium provided a strong fluorescent signal that was, on average, approximately 695 times brighter than the unstained controls. This result indicates that all freeze-dried platelet derivatives samples were expressing, or comprised, PS. Incubating the freeze-dried platelet derivatives with TRAP-6 did not cause a notable increase in AV binding as measured by mean fluorescent intensity (MFI) (Fig. 35B). The average MFI values for freeze-dried platelet derivatives incubated with buffer and freeze-dried platelet derivatives incubated with TRAP-6 were 68,179 and 68,783, respectively (Table 32).

[000612] Table 31

[000613] Table 32

[000614] Freeze-dried platelet derivatives, manufactured using the TFF process as described in Example 1, were shown to contain phosphatidylserine (PS) on the membrane as evident by the binding of Annexin V (AV) to the freeze-dried platelet derivatives. The binding of AV to activated platelets is a calcium dependent binding and therefore the calcium ion dependency of AV binding to the rehydrated freeze-dried platelet derivatives provide further support that the AV conjugate was not associating with the membrane of the freeze-dried platelet derivatives in a nonspecific manner.

[000615] While TRAP-6 was shown to activate apheresis platelets, as evident by increased CD62P expression, and increased the binding of AV to the activated platelet, it was not the case for the freeze-dried platelet derivatives. The freeze-dried platelet derivatives with or without a TRAP-6 incubation exhibited same high level of AV binding, and indicate that TRAP-6 does not promote further surface expression of PS for freeze-dried platelet derivatives, likely because the freeze-dried platelet derivatives are maximally activated during the lyophilization and/or rehydration process, and further stimulation/activation is not possible.

[000616] Example 19. Presence of Thrombospondin (TSP1) on the surface of the freeze-dried platelet derivatives

[000617] Thrombospondin (TSP1), a glycoprotein typically found to coat external membranes of activated platelets, was found to coat freeze-dried platelet derivatives without activation. The presence of TSP1 was detected by fluorescence of anti-Thrombospondin-1 (TSP-1) antibody.

[000618] Fresh platelet rich plasma (PRP) was isolated by centrifuging whole blood collected in acid citrate dextrose (ACD) at 180g for 10 minutes. Isolated PRP was centrifuged again at 823g for an additional 10 minutes. The plasma was then removed and discarded, and the platelet pellet was resuspended in HEPES Modified Tyrode’s Albumin (HMTA) buffer. An aliquot of the resulting washed platelet sample was activated by incubated the platelets at room temperature for 10 minutes in the presence of 2 mM GPRP peptide (BaChem Cat# H-1998.0025), 2 mM CaCE, 0.5 U/mL thrombin (EDM Millipore Cat# 605190- 1000U), and 0.5 pg/mL collagen (ChronoPar Cat# 385). A separate aliquot of washed platelets was set aside to be used as a resting negative control.

[000619] All samples of freeze-dried platelet derivatives were manufactured using the TFF process as described in Example 1. The freeze-dried platelet derivatives studied in this example were baked freeze- dried platelet derivatives which were heated after lyophilization at 80°C for 24 hours. All vials were rehydrated using the appropriate amount of cell culture grade water. After water was added, the vials were incubated for 10 minutes at room temperature. Gentle swirling of the vials was performed every 2 minutes during the 10-minute period to promote full dissolution of the cake. Once rehydrated, samples of freeze- dried platelet derivatives from each vial, along with samples from both the resting and activated fresh washed platelet aliquots, were diluted 1:500 in triplicate using phosphate buffered saline (PBS) (Coming Cat# 21-040-CV). The diluted samples were analyzed on the Quanteon flow cytometer and the concentrations of the platelets and freeze-dried platelet derivatives were determined. Based on these concentrations, an aliquot of each freeze-dried platelet derivatives or fresh platelet sample was diluted to a concentration of 100,000 freeze-dried platelet derivatives per micro liter.

[000620] Stained samples from each vial of freeze-dried platelet derivatives and the resting and activated fresh platelets were generated by adding 10 pL of diluted freeze-dried platelet derivatives or platelets to 20 pL of HMTA containing 4 pg/mL of anti-Thrombospondin-1 (TSP-1) antibody (Santa Cruz Biotech Cat# sc-59887 AF594). Unstained control samples were generated by adding 10 pL of diluted freeze-dried platelet derivatives or platelets to 20 pL of HMTA. All the samples were incubated at room temperature, protected from light, for 20 minutes. After incubation, 500 pL of PBS was added to all samples. One hundred microliters from each sample were transferred to an individual well in a 96 well plate, and the samples were analyzed using an Agilent Quanteon flow cytometer.

[000621 ] Unstained samples of fresh platelets and freeze-dried platelet derivatives generated little to no fluorescent signal, indicating that the samples were not auto fluorescent at the wavelength selected to measure TSP-1 expression or presence. Binding of the anti-TSP-1 antibody to fresh platelets increased slightly after activation with collagen and thrombin as shown by an increase in mean fluorescent intensity (MFI) when analyzed using flow cytometry (1,223 vs 3,306). Expression or presence of TSP-1 on freeze- dried platelet derivatives samples varied from lot to lot with an average MFI value of 91,448 (Fig. 36). For all freeze-dried platelet derivatives samples tested, the fluorescent signal was significantly higher than the signal generated by either resting or fresh platelets, indicating high amounts of TSP- 1 may be bound to the surface of rehydrated freeze-dried platelet derivatives. This data suggests that the freeze-dried platelet derivatives without the requirement of an activation step exhibit properties which in certain embodiments and applications are superior to activated platelet properties.

[000622] Example 20. Presence of von Willebrand factor (vWF) on the surface of the freeze- dried platelet derivatives

[000623] Fresh platelet rich plasma (PRP) was isolated by centrifuging whole blood collected in acid citrate dextrose (ACD) at 180g for 10 minutes. Isolated PRP was centrifuged again at 823g for an additional 10 minutes. The plasma was then removed and discarded, and the platelet pellet was resuspended in HEPES Modified Tyrode’s Albumin (HMTA) buffer. An aliquot of the resulting washed platelet sample was activated by incubating the platelets at room temperature for 10 minutes in the presence of 2 mM GPRP peptide (BaChcm Cat# H-1998.0025), 2 mM CaCE ), 0.5 U/mL thrombin (EDM Milliporc Cat# 605190- 1000U), and 0.5 qg/mL collagen (ChronoPar Cat# 385). A separate aliquot of washed platelets was set aside to be used as a resting negative control. All samples of freeze-dried platelet derivatives were prepared using the TFF process as described in the Example 1. The freeze-dried platelet derivatives studied in this example were baked freeze-dried platelet derivatives which were heated after lyophilization at 80°C for 24

177

RECTIFIED SHEET (RULE 91 ) ISA/EP hours. All vials were rehydrated using the appropriate amount of cell culture grade water (Coming Cat# 25 -055 -CI). After water was added, the vials were incubated for 10 minutes at room temperature. Gentle swirling of the vials was performed every 2 minutes during the 10-minute period to promote full dissolution of the cake. Once rehydrated, samples of freeze-dried platelet derivatives from each vial, along with samples from both the resting and activated fresh washed platelet aliquots, were diluted 1:500 in triplicate using phosphate buffered saline (PBS). The diluted samples were analyzed on the Quanteon flow cytometer and the concentrations were determined. Based on these concentrations, an aliquot of each freeze-dried platelet derivatives or fresh platelet sample was diluted to a concentration of 100,000 freeze-dried platelet derivatives per microliter.

[000624] Prior to staining, the anti -Von Willebrand Factor antibody (Novus Biologicals Cat# NBP2- 54379PE) was diluted by a factor of 10. Stained samples from each vial of freeze-dried platelet derivatives and the resting and activated fresh platelets were generated by adding 10 pL of diluted freeze-dried platelet derivatives or platelets to 10 pL of diluted antibody and 10 pL of HMTA. Unstained control samples were generated by adding 10 pL of diluted freeze-dried platelet derivatives or platelets to 20 pL of HMTA. All The samples were incubated at room temperature, protected from light, for 20 minutes. After incubation, 500 pL of PBS was added to all samples. One hundred microliters from each sample was transferred to an individual well in a 96 well plate, and the samples were analyzed using an Agilent Quanteon flow cytometer.

[000625] Unstained samples of fresh platelets and freeze-dried platelet derivatives generated little to no fluorescent signal, indicating that the samples were not auto fluorescent at the wavelength selected to measure vWF expression or presence. Binding of the anti-vWF antibody to fresh platelets increased after activation with collagen and thrombin as shown by an increase in mean fluorescent intensity (MFI) when analyzed using flow cytometry (4,771 vs 19,717). Expression or presence of vWF on freeze-dried platelet derivatives samples varied from lot to lot with an average MFI value of 13,991 (Fig. 37). For all freeze- dried platelet derivatives samples tested, the fluorescent signal fell between the signals generated by resting and activated platelets. This suggests that vWF is present on the surface of rehydrated freeze-dried platelet derivatives, and that the amount of vWF present is greater than that seen on resting platelets. The data suggests that even in the absence of any activation, the freeze-dried platelet derivatives exhibit properties that is superior to resting platelets and similar to the activated platelets.

[000626] Example 21. Lyophilized Fixed Platelet and Freeze-dried platelet derivatives Flow Cytometry

[000627] The presence of von Willebrand factor, Thrombospondin- 1, and fibrinogen, which can be desired properties for some uses of platelet derivatives, were analyzed by respective antibody binding and the MFI (mean fluorescence intensity) assay for lyophilized fixed platelets and freeze-dried platelet derivatives.

[000628] Method

[000629] All samples of freeze-dried platelet derivatives were prepared using the TFF process as described in Example 1. All vials of freeze-dried platelet derivatives were rehydrated using the appropriate amount of cell culture grade water. After water was added, the vials were incubated for 10 minutes at room temperature. Gentle swirling of the vials was performed every 2 minutes during the 10-minute period to promote full dissolution of the cake. Fixed lyophilized platelets (Chrono-Log Corp Cat#299-9-) were rehydrated using Tris buffered saline (TBS) (Chrono-Log Corp Cat# 299-5) according to the manufacturer’s instruction. Once rehydrated, samples of freeze-dried platelet derivatives from each vial, along with a sample of the lyophilized fixed platelets, were diluted 1:500 in triplicate using phosphate buffered saline (PBS) (Coming Cat# 21-040-CV). The diluted samples were analyzed on the Quanteon flow cytometer and the concentrations were determined. Based on these concentrations, an aliquot of each freeze-dried platelet derivatives or fresh platelet sample was diluted to a concentration of 100,000 freeze-dried platelet derivatives per microliter. Prior to staining, the anti-VWF antibody was diluted 1: 10 (part to whole) in HMTA and the anti -TSP- 1 antibody was diluted 1:5 (part to whole) in HMTA. Single stained samples from each vial of freeze-dried platelet derivatives or fixed lyophilized platelets were generated by combining 10⁶ total cells diluted in HEPES Modified Tyrode’s Albumin (HMTA) buffer (Boston Bioproducts, Inc. Cat# C-9234C) with one of the following: 2 pL anti-CD42b antibody (Milli Mark Cat# FCMAB196P), 10 pL anti- von Willebrand Factor antibody (Novus Biologicals CAT# NBP2-54379PE), 3 pL anti- Thrombospondin-1 (TSP-1) antibody (Santa Cruz Biotech Cat# sc-59887 AF594 ), or 5 pL anti-fibrinogen antibody (BioCytex Cat# 5009-F100T). All The samples were incubated at room temperature, protected from light, for 20 minutes. After incubation, 500 pL of PBS was added to all samples. One hundred microliters from each sample was transferred to an individual well in a 96 well plate, and the samples were analyzed using an Agilent Quanteon flow cytometer.

[000630] Results

[000631] The resulting MFI values from these experiments are shown in FIGS. 38A-38C The data suggests that the addition of the fixation step appears to reduce the amount of pro-adhesive molecules that bind to the cell membrane during the lyophilization and/or rehydration process. Specifically, this experiment demonstrated the freeze-dried platelet derivative surface contains greater quantities of von Willebrand factor, Thrombospondin- 1, and fibrinogen as compared to that of the fixed human platelets.

[000632] Example 22. Freeze-dried platelet derivatives - compromised membrane [000633] Membrane integrity of freeze-dried platelet derivatives, either heated at 80°C for 24hours

(baked freeze-dried platelet derivatives) or not heated (unbaked freeze-dried platelet derivatives) after lyophilization, was tested. The baked and unbaked Freeze-dried platelet derivatives of the standard formulation were analyzed by forward scatter against pre -lyophilization material and by the use of an antibody against a stable intracellular antigen, p-tubulin, to determine if freeze-dried platelet derivatives were permeable to IgGs (150 kDa). Forward scatter is a flow cytometry measurement of laser scatter along the path of the laser. Forward scatter (FSC) is commonly used as an indication of cell size as larger cells will produce more scattered light. However, forward scatter also can indicate the membrane integrity of the sample via optical density (i.e., light transmission); a cell with less cytosolic material and a porous membrane would transmit more light (have a lower FSC) than the same cell if intact, despite being the same size.

[000634] The freeze-dried platelet derivatives of Example 1 were studied to determine if freeze-dried platelet derivatives were permeable to IgGs (150 kDa) by the use of an antibody against a stable intracellular antigen, p-tubulin. Fresh platelets, unbaked freeze-dried platelet derivatives, and baked freeze-dried platelet derivatives were fixed and stained with anti-P tubulin IgG with and without cell permeabilization. Fresh platelets showed a dramatic increase in IgG binding with permeabilization, whereas both baked and unbaked freeze-dried platelet derivatives showed no change in response to permeabilization (Table 33). Results from fresh platelets and freeze-dried platelet derivatives that were fixed and then either permeabilized with 0.2% Triton-X 100 or not permeabilized and then stained with anti-P tubulin IgG conjugated to the fluorophore AF594. Unstained samples are included for background fluorescence.

[000635] Table 33

[000636] The IgG binding studies suggest that the membrane integrity of freeze-dried platelet derivatives is severely impaired such that large molecules can pass through the cell membrane. Of additional note, permeabilization induced decreases in forward scatter value, corroborating the proposed relationship between membrane integrity and optical density for particles of the same size.

[000637] Additionally, the mean intensity of forward light scattering of freeze-dried platelet derivatives prepared by TFF method as described in Example 1 was compared to in-date human platelet apheresis units. The method is as described below.

[000638] All samples of freeze-dried platelet derivatives were manufactured using the TFF process. All vials were rehydrated using the appropriate amount of cell culture grade water (Coming Cat# 25-055- CI). After water was added, the vials were incubated for 10 minutes at room temperature. Gentle swirling of the vials was performed every 2 minutes during the 10-minute period to promote full dissolution of the cake. Once rehydrated, samples of freeze-dried platelet derivatives from each vial, along with samples from both in-date human platelet apheresis units, were diluted 1:500 in triplicate using phosphate buffered saline (PBS) (Coming Cat# 21-040-CV). The diluted samples were acquired on the Quanteon flow cytometer and the concentrations were determined. Based on these concentrations, an aliquot of each freeze-dried platelet derivatives or apheresis platelet sample was diluted to a concentration of 100,000 freeze-dried platelet derivatives per microliter in HEPES Modified Tyrode’s Albumin (HMTA) buffer (Cellphire RGT-004).

[000639] Unstained samples of freeze-dried platelet derivatives and human apheresis platelets containing 10⁶ total cells in HMTA were diluted with 500 pL of PB. One hundred microliters from each sample were transferred to an individual well in a 96 well plate, and the samples were analyzed using an Agilent Quanteon flow cytometer.

The mean intensity is depicted in Fig. 39. It can be observed that the mean intensity of forward light scattering measured with flow cytometry is distinctly lower (about 50%) for freeze-dried platelet derivatives as compared to the apheresis plasma. Therefore, corroborating with the previous result of Table 33 that a cell with less cytosolic material and a porous membrane would transmit more light (have a lower FSC) than the same cell if intact, despite being the same size.

[000640] The overall results suggest that membrane integrity is substantially degraded in freeze- dried platelet derivatives; the platelet intracellular contents have been released (e.g. LDH) and large molecules can enter the cellular cytosol (e.g. anti P-tubulin IgG). The plasma membrane of freeze-dried platelet derivatives is likely damaged by the drying (sublimation) or rehydration processes as freezing in cryopreserved platelets appears to be insufficient to induce severe membrane dysfunction. These results also imply that signal transduction from the outside of the cell is not possible in freeze-dried platelet derivatives, which is corroborated by lack of aggregation response (as observed in Example 17). Baking, although it produced an increase in optical density, did not appear to improve membrane integrity significantly (e.g., IgG [3-tubulin binding). The results discussed in the present example thus show that the platelet derivatives as disclosed herein have a compromised plasma membrane.

[000641] Example 23. Freeze-Dried Platelet Derivate Clinical Trial, A Dose and Impact on Bleeding Study

[000642] Freeze-dried platelet derivatives at low, medium and high doses, are compared to liquid stored platelets (LSP) in their effectiveness to cease or decrease bleeding. Freeze-dried platelet derivatives have a short circulation time and are not expected to increase the platelet count immediately post infusion. As such, clinical presentation of the patient is used to evaluate bleeding during the treatment phase and guide the treatment scheme rather than only platelet count.

[000643] The Study

[000644] A prospective, multicenter, randomized, open-label, Phase 2, parallel, dose ranging, multidose trial enrolls patients into three freeze-dried platelet derivatives dose groups and one control liquid stored platelets (LSP) group in order to evaluate, in a dose-escalation manner, the impact on bleeding, and the preliminary effect on coagulation measures of increasing doses of allogeneic freeze-dried platelet derivatives. Freeze-dried platelet derivatives are prepared according to Example 1. The freeze-dried platelet derivatives in dried form with components of the mixture in which platelets were freeze-dried to form the freeze-dried platelet derivates (platelet derivative composition in the form of a powder), were resuspended in water and delivered in one of three doses indicated herein in Table 34.

[000645] The patients, 160 total selected, are: 18 years and older, female or male, that meet the following inclusion criteria:

1. Adults (>18 years) with total circulating platelets (TCP) as defined by both (a) and (b): a. a count of between 10,000 and 70,000 platelets/pL blood, inclusive b. any one or more of (i-iii) : i. confirmed diagnosis of hematologic malignancy, myeloproliferative disorder, myelodysplastic syndrome, or aplasia ii. undergoing chemotherapy, immunotherapy, radiation therapy or hematopoietic stem cell transplantation iii. refractory to platelet transfusion defined as two 1-hour corrected count increment (CCI) of <5000 on consecutive transfusions of LSP (Sacher, 2003)

2. WHO Bleeding Score of 2 excluding cutaneous bleeding

3. All patients provide informed consent directly or through a legally authorized representative, comply with treatment and monitoring, and all women of childbearing potential test negative for pregnancy. [000646] A maximum of 6 doses of the freeze-dried platelet derivatives are allowed to be administered in a 72-hour period to treat enrolled bleeding patients. The study evaluates the safety and potential efficacy of three different doses of freeze-dried platelet derivatives v/s control. Freeze-dried platelet derivatives Low Dose, Medium Dose, High Dose, or control (LSP) are listed in Table 34. The medium dose is higher than the low dose, and the high dose is higher than the medium dose. [000647] Table 34

N/A = not applicable; NOD = non-obese diabetic; SCID = severe combined immunodeficiency; TGPU = thrombin generating potency unit.

[000648] The specific outcomes analyzed are tabulated below in Table 35.

[000649] Table 35

[000650] Patients with the following criteria are excluded from the study:

[000651] Patient Exclusion Criteria:

1. Any disorder or condition related to thrombosis, embolism, vascular occlusion, or ischemia (except when a prior history of central line thrombosis has resolved), including but not limited to: past history or current diagnosis of arterial or venous thromboembolic disease including acute coronary syndrome, peripheral vascular disease, and retinal arterial or venous thrombosis, MI, stent placement, valve replacement and/or repair, sinusoidal obstruction syndrome (venoocclusive disease) or cytokine storm syndrome associated with CAR-T cell therapy

2. Refusal to accept blood products 3. Liver enzyme blood levels greater than 3 x the upper limit of normal (ULN)

4. Blood creatinine level greater than 3 x ULN

5. Received platelet inhibitor drugs, cyclooxygenase-2 (COX-2) inhibitors, or nonsteroidal anti-inflammatory drugs within 5 days prior to infusion

6. Currently receiving anticoagulant therapy or antiplatelet therapy

7. Receipt of any pro-coagulant agents other than tranexamic acid (TXA) [e.g., desmopressin (DDAVP), recombinant Factor Vila or prothrombin complex concentrates (PCC)] within 48 hours of first infusion, or with known hypercoagulable state

8. WHO Bleeding Score of 2 solely due to cutaneous bleeding such as petechia, ecchymosis, or bruising

9. Receiving L-asparaginase as part of a current cycle of treatment

10. Known inherited or acquired bleeding disorder including, but not limited to: acquired storage pool deficiency or paraproteinemia with platelet inhibition

11. Known inherited or acquired prothrombotic disorders, including antiphospholipid syndrome (Those with lupus anticoagulant or positive antiphospholipid serology without thrombosis are NOT excluded.)

12. Anuria

13. On dialysis

14. Receipt of an investigational drug within 1 month before first infusion, other than for treatment of their underlying disease

15. Female s pregnant or nursing or unwilling to use contraception during and for 30 days after taking the study product (females). Evidence of effective birth control may be used, at the discretion of the physician

16. Acute or chronic medical disorder that, in the opinion of the Investigator, would impair the ability of the patient to receive or respond to study treatment

17. Prior participation in this study with successful infusion of the investigational or control product

18. Currently enrolled in other trials not related to their primary disease process or involving platelet transfusions, platelet growth factors, or other pro-coagulant agents

[000652] Patients who signed the informed consent form and met the inclusion criteria but not the exclusion criteria are treated by administration of freeze-dried platelet derivative compositions according to one of the three active arms of the study or the control arm as provided in Table 34. The outcomes listed immediately above are analyzed at the timepoints indicated above for each outcome to assess the safety and efficacy of the freeze-dried platelet derivative compositions at the three different doses for the listed outcomes/indications .

[000653] Example 24. Characterization of different lots of FDPD compositions

[000654] Different lots of freeze-dried platelet derivative (FDPD) compositions were produced using the TFF method provided in Example 1. Flow cytometry studies were performed on the FPD compositions using the method provided in Example 6.

[000655] Table 36

[000656] Table 36 provides the properties of the platelet derivatives of different lots that were produced by the method provided in Example 1. It can be appreciated that the platelet derivatives are positive for cell surface markers such as CD 41, CD 62, and Annexin V, and the positive particles are between the size range of 0.5 to 2.5 pm. It can be observed that in the particles larger than 2.5 pm or smaller than 0.5 pm the cell surface markers are not observed.

[000657] Example 25. FDPDs Increase Survival Rate of NOD/SCID Mice in the Presence of Clopidogrel and Aspirin

[000658] Mice treated with anti -platelet agents clopidogrel and aspirin, were further treated with human FDPDs, varying in count, to assess the effect of the FDPDs on hemostasis.

[000659] Human FDPDs were prepared according to the method as described in Example 1. The FDPD were rehydrated with sterile water equivalent to fdl volume prior to lyophilization.

Mice (n=12) were treated with clopidogrel at 5mg/kg and aspirin at 3mg/kg for 3 days. The mice were then anesthetized, the tail was snipped off at 1mm diameter and submerged in warm saline water. Animals were syringe injected, into a vein or artery, with saline or 1.6 x 10⁹/kg, 4 x 10⁹/kg or 6.5 x 10⁹/ kg of FDPDs of equal volume (80pL). Figure 40 shows an increase in the number of animals that stopped bleeding when administered FDPDs in comparison to saline. The lower dose (1.6 x 10⁹/kg) did not show any change in bleed time and is not included in graph. The two higher doses (4 x 10⁹/kg and 6.5 x 10⁹/ kg of FDPDs) showed an increase in the number of animals that stopped bleeding, thus returning to normal hemostasis, in comparison to saline administration.

[000660] Example 26. Light Transmission Aggregometry (LTA) to Confirm Inhibitory Effect of Prasugrel and Aspirin on Patient Platelets

[000661 ] Evaluation of platelet aggregation was conducted on platelets obtained from patient blood on a regimen of prasugrel and aspirin. Whole blood from a patient on a regimen of prasugrel and aspirin was collected in 3.2% sodium citrate tubes (BD #363083). Platelet rich plasma (PRP) was generated by centrifugation of whole blood for 10 minutes at a relative centrifugal force (RCF) of 180 x g and removal of the top PRP layer. The remainder of the tube was centrifuged for 10 minutes at a RCF of 1800 x g and the top platelet poor plasma (PPP) layer was removed. The PRP was adjusted to 200,000 platelets/pL with PPP.

[000662] Light Transmission aggregometry was performed on the PAP-8E aggregometer (Bio/Data Corporation) following the manufacture’s recommendations. A 225pL PRP sample was placed in test tubes (Bio/Data Corporation #101521) with a stir bar (Bio/Data Corporation #105990) and warmed at 37°C for 5 minutes prior to adding 25 pL of the agonist. The final concentrations for the agonists in the PRP sample were: 0.5mM for arachidonic acid (AA) (Chronolog Corporation #390), lOuM for ADP (Chronolog Corporation #384), and 40pM for TRAP-6 (Millipore Sigma #T1573). TRAP-6 was used as the positive control in the LTA test. Fig 41 confirms that patient’s platelet aggregation activity is inhibited by prasugrel and aspirin.

[000663] Example 27. FDPDs Contribute to an Increase of Endogenous CD41/CD62P Expression in the Presence of Dual Antiplatelet Therapy (DAPT), In-vitro Experiment

[000664] Analysis of endogenous CD41/CD62P expression was conducted on donor blood treated, in-vitro, with ticagrelor and aspirin. The effect of FDPDs, varying in dose, on CD41/CD62P expression was assessed.

[000665] Human FDPDs were prepared according to the method as described in Example 1. The FDPDs were rehydrated with sterile water equivalent to the fill volume prior to lyophilization.

[000666] Whole blood was collected in 3.2% sodium citrate tubes (BD #363083). Blood was either treated with dual anti -platelet therapy (DAPT) consisting of a final concentration of lOOpM aspirin (Cayman chemical #70260) plus Ipg/mL ticagrelor (Sigma #SML2482) or left untreated (NT). Blood was incubated for 10 minutes on a rocker. Next, samples were treated with FDPDs at 10, 20, and 50 k/pL (k/pL = 10³ FDPDs/pL) and incubated for 10 minutes on the rocker. Following the treatments, blood samples were fixed in a 1: 1 ratio with ThromboFix (Beckman Coulter #6607130) and incubated for 1 hour at room temperature. The fixed whole blood (5pL) was combined with 5pL of anti-CD41-PE (Beckman Coulter # IM1416U), 5pL anti-CD62P-PECy5 (BD #551142), and 85pL HMTA buffer. The stained sample was incubated for 20 minutes at room temperature. After incubation 5pL of stained blood was then diluted in 95pL of PBS and analyzed on the Acea NovoCyte Quanteon flow cytometer (Agilent).

[000667] Data analysis was performed using NovoExpress® software (Agilent) by first gating on all endogenous CD41 -positive events, followed by all endogenous CD62P-positive events, and then graphed as a percentage of total double-positive events (Figure 42). Three independent experiments are graphed with error bars representing standard deviation. [000668] Figure 42 shows FDPDs dose dependent increase in the percent CD41/CD62P positive events of donor blood treated in vitro with ticagrelor and aspirin. This dose dependent response supports the ability of FDPDs to improve coagulation response (reflected by the increasing endogenous positivity of CD41/CD62P) in the presence of DAPT.

[000669] Example 28. FDPDs Contribute to an Increase of Endogenous CD41/CD62P Expression in the Presence of Dual Antiplatelet Therapy (DAPT), Ex -vivo Experiment

[000670] Analysis of endogenous CD41/CD62P expression was conducted on blood obtained from patients taking prasugrel and aspirin, and further treated with varying doses of FDPDs. Human FDPDs were prepared according to the method as described in Example 1. The FDPDs were rehydrated with sterile water equivalent to the fdl volume prior to lyophilization.

[000671] Whole blood from a donor on a regimen of prasugrel and aspirin was collected in 3.2% sodium citrate tubes (BD #363083). Blood was aliquoted to microcentrifuge tubes, treated with FDPD concentrations of 10, 20, and 50k/pL (k/pL = 10³ FDPDs/uL), and incubated for 10 minutes on the rocker. Following the treatments, blood samples were fixed in a 1: 1 ratio with ThromboFix (Beckman Coulter #6607130) and incubated for 1 hour at room temperature. The fixed whole blood (5pL) was then stained by adding 5pL of anti-CD41-PE (Beckman Coulter # IM1416U), 5pL anti-CD62P-PECy5 (BD #551142), and 85 pL HMTA buffer. The stained blood was incubated for 20 minutes at room temperature and 5pL of stained blood was then diluted in 95 pL of PBS and analyzed on the Acea NovoCyte Quanteon flow cytometer (Agilent).

[000672] Data analysis was performed in NovoExpress® software (Agilent) by gating on all endogenous CD41 positive followed by all endogenous CD62P positive events and then graphed as a percentage of total double-positive events (Figure 43). The no treatment (NT) group is from three separate in vitro experiments and is graphed next to the DAPT donor results for comparison.

[000673] Figure 43 shows a FDPDs dose dependent increase in the percent CD41/CD62P positive events in ex-vivo analysis of patient on regimen of prasugrel and aspirin.

[000674] The replication of the dose dependent response in the ex vivo experiment (Figure 43) further supports the ability of FDPDs to improve coagulation response (reflected by the increasing endogenous positivity of CD41/CD62P) in the presence of DAPT.

[000675] Example 29: FDPDs Increase Release of PF4 in the Presence of Dual Antiplatelet Therapy, In-vitro Experiment [000676] Analysis of PF4 release was conducted on donor blood treated in-vitro, with ticagrelor and aspirin, and further treated with varying doses of FDPDs.

[000677] Human FDPDs were prepared according to the method as described in Example 1. The FDPDs were rehydrated with sterile water equivalent to the fdl volume prior to lyophilization.

[000678] Whole blood from healthy donors was collected in 3.2% sodium citrate tubes (BD #363083). Blood was either treated with dual anti-platelet therapy (DAPT) consisting of a final concentration of lOOuM aspirin (Cayman chemical #70260) plus Ipg/mL ticagrelor (Sigma #SML2482) or left untreated (NT). Blood was incubated for 10 minutes on a rocker. Blood was then aliquoted to microcentrifuge tubes and treated with FDPDs at concentrations of 10, 20, 50 k/pL (k/pL = 10³ FDPDs/pL) and incubated for 10 minutes on the rocker. Following treatment, blood was centrifuged at a RCF of 1800 x g for 10 minutes, and the top layer of platelet poor plasma (PPP) was collected into fresh microcentrifuge tubes.

[000679] The PPP samples were then diluted 1:500 in Calibrator Diluent (supplied by kit) and run according to manufacturer’s instructions using the R&D Systems, Human CXCL4/PF4 Quantikine ELISA kit. Absorbance was read at 450nm using a Tecan plate reader. Data was analyzed using GraphPad Prism. Figure 44 shows that FDPDs increase the release of PF4 (an indicator of platelet activation) in the presence of ticagrelor and aspirin in-vitro.

[000680] Example 30: FDPDs Increase Release of PF4 in the Presence of Dual Antiplatelet Therapy, Ex-vivo Experiment

[000681] Analysis of PF4 release was conducted on blood obtained from patients taking prasugrel and aspirin, and further treated with varying doses of FDPDs. Human FDPDs were prepared according to the method as described in Example 1. The FDPDs were rehydrated with sterile water equivalent to the fill volume prior to lyophilization.

[000682] Whole blood from a patient on a regimen of prasugrel and aspirin and a healthy donor taking no antiplatelet medications was collected in 3.2% sodium citrate tubes (BD #363083). Blood was then aliquoted to microcentrifuge tubes and treated with FDPDs at concentrations of 10, 20, 50 k/pL (k/pL = 10³ FDPDs/pL) and incubated for 10 minutes on the rocker. Following treatment, blood was centrifuged at a RCF of 1800 x g for 10 minutes, and the top layer of platelet poor plasma (PPP) was collected into fresh microcentrifuge tubes.

[000683] The PPP samples were diluted 1:500 in Calibrator Diluent (supplied by kit) and run according to manufacturer’s instructions using the R&D Systems, Human CXCL4/PF4 Quantikine ELISA kit. Absorbance was read at 450 nm using a Tecan plate reader. Data was analyzed using GraphPad Prism. Figure 45 shows that FDPDs increase the release of PF4 (an indicator of platelet activation) in the presence of prasugrel and aspirin ex vivo.

[000684] Example 31. FDPDs Affect Thrombin Generation in the Presence of Dual Antiplatelet

Therapy (DAPT), In-vitro Experiment

[000685] Analysis of thrombin generation by Platelet Rich Plasma (PRP), obtained from donor blood treated in-vitro, with ticagrelor and aspirin, and further treated with varying doses of FDPDs, was performed.

[000686] Human FDPDs were prepared according to the method as described in Example 1. The FDPDs were rehydrated with sterile water equivalent to the fdl volume prior to lyophilization.

[000687] Whole blood from healthy donors taking no antiplatelet medications was collected in 3.2% sodium citrate tubes (BD #363083). Blood was either treated with dual anti-platelet therapy (DAPT) consisting of a final concentration of lOOpM aspirin (Cayman chemical #70260) plus Ipg/mL ticagrelor (Sigma #SML2482) or left untreated (NT). Blood was incubated for 10 minutes on a rocker. Platelet rich plasma (PRP) was generated by centrifugation of whole blood for 10 minutes at a RCF of 180 x g and removal of the top PRP layer. The remainder of the tube was centrifuged for 10 minutes at a RCF of 1800 x g and the top platelet poor plasma (PPP) layer was removed. The PRP was adjusted to 200,000 platelets/pL with PPP.

[000688] Thrombin Calibrator reagent (Stago #86192) was prepared according to manufacturer’s guidelines 20pL of the thrombin calibrator reagent was added to each calibration well, and 20pL of PBS was added to each Thrombin Generation well. PRP was aliquoted into microcentrifuge tubes and treated with FDPDs at 2 and 20 k/pL (k=10³ FDPD/pL). Samples were diluted 1: 10 in Octaplas® and a multichannel pipette was used to add 80pL of the diluted sample to each of the assay wells in an assay plate (calibration and thrombin generator wells).

[000689] The assay plate was inserted into a Thrombinoscope (Stago) connected to a computer with

CAT software running. The assay plate was incubated at 37°C for 10 min. During plate incubation Fluo- substrate and Fluo-buffer (Stago #86197) were combined according to manufacturer’s guidelines to obtain FluCa buffer. ADP (Chronolog #384) and PGE1 (Cayman #13010) were added to FluCa buffer. ADP was added to FluCa buffer to obtain a final concentration of IpM of ADP in assay wells and PGE1 was added to FluCa buffer to obtain a final concentration of 20nM of PGE1 in the assay wells. After incubation 20pL FluCa solution was injected into each well. Thrombin Generation was read for 180 min at 40 second intervals. Data analysis was performed in GraphPad Prism. Figures 46A and 46B show a reduced time to peak and increased velocity index of thrombin production with the addition of FDPDs to the PRP obtained from donor blood treated with ticagrelor and aspirin. [000690] Example 39. FDPDs Affect Thrombin Generation in the Presence of Dual Antiplatelet Therapy (DAPT), Ex-vivo Experiment

[000691 ] Analysis of thrombin generation by Platelet Rich Plasma (PRP) obtained from blood of patients on a regiment of prasugrel and aspirin and further treated with varying doses of FDPDs, was performed. Human FDPDs were prepared according to the method as described in Example 1. The FDPDs were rehydrated with sterile water equivalent to the fdl volume prior to lyophilization.

[000692] Whole blood from a patient on a regimen of prasugrel and aspirin and a healthy donor taking no antiplatelet medications was collected in 3.2% sodium citrate tubes (BD #363083). Platelet rich plasma (PRP) was generated by centrifugation of whole blood for 10 minutes at a RCF of 180 x g and removal of the top PRP layer. The remainder of the tube was centrifuged for 10 minutes at a RCF of 1800 x g and the top platelet poor plasma (PPP) layer was removed. The PRP was adjusted to 200,000 platelets/pL with PPP.

[000693] Thrombin Calibrator reagent (Stago #86192) was prepared according to manufacturer’s guidelines. 20pL of the thrombin calibrator reagent was added to each calibration well, and 20pL of PBS was added to each Thrombin Generation well. PRP was aliquoted into microcentrifuge tubes and treated with FDPDs at 2 and 20 k/pL (k=10³ FDPD/pL). Samples were diluted 1: 10 in Octaplas® and a multichannel pipette was used to add 80pL of the diluted sample to each of the assay wells of an assay plate (calibration and thrombin generator wells).

[000694] The assay plate was inserted into Thrombinoscope (Stago) connected to a computer with CAT software running. The assay plate was incubated at 37°C for 10 min. During plate incubation Fluo- substrate and Fluo-buffer (Stago #86197) were combined according to manufacturer’s guidelines to obtain FluCa buffer. ADP (Chronolog #384) and PGE1 (Cayman #13010) were added to FluCa buffer. ADP was added to FluCa buffer to obtain a final concentration of IpM of ADP in assay wells and PGE1 was added to FluCa buffer to obtain a final concentration of 20nM of PGE 1 in the assay wells. After plate incubation, 20pL FluCa solution was injected into each well. Thrombin generation was read for 180 min at 40 second intervals. Data analysis was performed in GraphPad Prism. Figures 47A and 48B show a reduced time to peak and increased velocity index of thrombin production with the addition of FDPDs to the PRP obtained from patient blood on a regimen of prasugrel and aspirin.

[000695] The disclosed embodiments, examples and experiments are not intended to limit the scope of the disclosure or to represent that the experiments below are all or the only experiments performed. Efforts have been made to ensure accuracy with respect to numbers used (e.g., amounts, temperature, etc.) but some experimental errors and deviations should be accounted for. It should be understood that variations in the methods as described may be made without changing the fundamental aspects that the experiments are meant to illustrate.

[000696] Those skilled in the art can devise many modifications and other embodiments within the scope and spirit of the present disclosure. Indeed, variations in the materials, methods, drawings, experiments, examples, and embodiments described may be made by skilled artisans without changing the fundamental aspects of the present disclosure. Any of the disclosed embodiments can be used in combination with any other disclosed embodiment.

[000697] In some instances, some concepts have been described with reference to specific embodiments. However, one of ordinary skill in the art appreciates that various modifications and changes can be made without departing from the scope of the invention as set forth in the claims below. Accordingly, the specification and figures are to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope of invention.

Claims

CLAIMS What is claimed is:

1. A platelet derivative composition for use in the treatment of a subject having an indication selected from the group consisting of intracranial hemorrhage (I CH), traumatic brain Injury (TBI), and Hermansky Pudlak Syndrome (HPS), wherein the treatment comprises rehydrating platelet derivatives in the platelet derivative composition to form a rehydrated platelet derivative composition and administering an effective dose of the platelet derivatives in the rehydrated platelet derivative composition to the subject, wherein the platelet derivative composition comprises a population of platelet derivatives comprising CD 41 -positive platelet derivatives, wherein less than 5% of the CD 41 -positive platelet derivatives are microparticles, having a reduced propensity to aggregate such that no more than 5% of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets, and having a potency of at least 1.5 thrombin generation potency units (TGPU) per 10⁶ platelet derivatives.

2. The platelet derivative composition of claim 1, wherein the indication is intracranial hemorrhage (ICH).

3. The platelet derivative composition of claim 1, wherein the indication is traumatic brain Injury (TBI).

4. The platelet derivative composition of claim 1, wherein the indication is Hermansky Pudlak Syndrome (HPS).

5. A platelet derivative composition for use in the treatment of a subject having an indication of immune thrombocytopenia (ITC), or Bernard Soulier syndrome, wherein the treatment comprises rehydrating platelet derivatives in the platelet derivative composition to form a rehydrated platelet derivative composition, and administering an effective dose of the platelet derivatives in the rehydrated platelet derivative composition to the subject, wherein the platelet derivative composition comprises a population of platelet derivatives comprising CD 41 -positive platelet derivatives, wherein less than 5% of the CD 41 -positive platelet derivatives are microparticles, having a reduced propensity to aggregate such that no more than 5% of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets, and having a potency of at least 1.5 thrombin generation potency units (TGPU) per 10⁶ platelet derivatives.

6. A platelet derivative composition for use in the treatment of a subject having an indication selected from the group consisting of Von Willebrand disease, immune thrombocytopenia, intracranial hemorrhage (ICH), traumatic brain Injury (TBI), Hermansky Pudlak Syndrome (HPS), Chemotherapy induced thrombocytopenia (CIT), Scott syndrome, Evans syndrome, Hematopoietic Stem Cell Transplantation, Fetal and neonatal alloimmune thrombocytopenia, Bernard Soulier syndrome, Acute myeloid leukemia, Glanzmann thrombasthenia, Myelodysplastic syndrome, Hemorrhagic Shock, Coronary thrombosis (myocardial infarction), Ischemic Stroke, Arterial Thromboembolism, Wiskott Aldrich Syndrome, Venous Thromboembolism, MYH9 related disease, Acute Lymphoblastic Lymphoma (ALL), Acute Coronary Syndrome, Chronic Lymphocytic Leukemia (CLL), Acute Promyelocytic Leukemia, Cerebral Venous Sinus Thrombosis (CVST), Liver Cirrhosis, Factor V Deficiency (Owren Parahemophilia), Thrombocytopenia absent radius syndrome, Kasabach Merritt syndrome, Gray platelet syndrome, Aplastic anemia, Chronic Liver Disease, Acute radiation syndrome, Dengue Hemorrhagic Fever, Pre-Eclampsia, Snakebite envenomation, HELLP syndrome, Haemorrhagic Cystitis, Multiple Myeloma, Disseminated Intravascular Coagulation, Heparin Induced Thrombocytopenia, Pre-Eclampsia, Labor And Delivery, Hemophilia, Cerebral (Fatal) Malaria, Alexander's Disease (Factor VII Deficiency), Hemophilia C (Factor XI Deficiency), Familial hemophagocytic lymphohistiocytosis, Acute lung injury, Hemolytic Uremic Syndrome, Menorrhagia, Chronic myeloid leukemia, or any combinations thereof, wherein the treatment comprises rehydrating platelet derivatives in the platelet derivative composition to form a rehydrated platelet derivative composition and administering an effective dose of the platelet derivatives in the rehydrated platelet derivative composition to the subject, and wherein the platelet derivative composition comprises a population of platelet derivatives comprising CD 41 -positive platelet derivatives, wherein less than 5% of the CD 41 -positive platelet derivatives are microparticles, having a reduced propensity to aggregate such that no more than 5% of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets, and having a potency of at least 1.5 thrombin generation potency units (TGPU) per 10⁶ platelet derivatives.

7. A plurality of containers each containing a platelet derivative composition in the form of a powder, wherein the platelet derivative composition comprises a population of platelet derivatives comprising CD 41 -positive platelet derivatives, wherein less than 5% of the CD 41 -positive platelet derivatives are microparticles having a diameter of less than 0.5 pm, having a reduced propensity to aggregate such that no more than 5% of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets, and having a potency of at least 1.5 thrombin generation potency units (TGPU) per 10⁶ platelet derivatives.

8. The plurality of containers of claim 7, wherein some platelet derivatives of the platelet derivative composition have different amino acid sequences for at least one protein associated with or part of the platelet derivatives.

9. The plurality of containers of claim 7, wherein the different amino acid sequences differ at one or more residues corresponding to amino acid residues encoded by a non-synonymous single nucleotide polymorphism (SNP).

10. The plurality of containers of claim 7, wherein the plurality of containers comprises the platelet derivative composition from at least 2 different lots in separate containers, and wherein one or more of: a) the amount of plasma protein in the powder of any two containers chosen from different lots, differs by less than 10%, and b) the amount of microparticles in the powder of any two containers chosen from different lots, differs by less than 10%.

11. The plurality of containers of claim 10, wherein the platelet derivative composition in at least one of the plurality of containers comprises or is associated with a first protein from a first gene that has a different amino acid sequence than found in all the versions of the first protein from the first gene in the platelet derivative composition in one or more other containers of the plurality.

12. The plurality of containers of claim 10, wherein the platelet derivative composition in each container comprises trehalose in the range of 20-35% by weight, polysucrose in the range of 45-60% by weight, and platelet derivatives in the range of 0.5-20% by weight.

196

13. The plurality of containers of claim 7, wherein plurality of containers comprises the platelet derivative composition from at least 3 different lots, and wherein the platelet derivative composition in at least 2 of the lots comprises a first protein from a first gene that has a different amino acid sequence than found in all the versions of the first protein from the first gene in the platelet derivative composition in one or more other containers of the plurality.

14. The plurality of containers of claim 7, wherein the amount of plasma protein in the powder of any two containers chosen from different lots, differs by less than 5%.

15. The plurality of containers of claim 7, wherein a percent of microparticles in the powder of any two containers chosen from different lots, differs by less than 10%.

16. The plurality of containers of claim 7, wherein an amount of platelet derivatives in the powder of any two containers chosen from different lots, differs by less than 10%.

17. The plurality of containers of claim 7, wherein each of the plurality of containers are purged with at least one inert gas.

18. The plurality of containers of claim 7, wherein the platelet derivative composition comprises trehalose in the range of 20-35% by weight, polysucrose in the range of 45-60% by weight, and platelet derivatives in the range of 0.5-20% by weight.

19. A process for preparing a platelet derivative composition comprising a population of platelet derivatives, the process comprising performing tangential flow filtration (TFF) of a platelet composition in a solution to at least partially exchange the solution with a preparation agent having a pH in the range of 5.5 to 8.0 and comprising 0.4 to 35% trehalose and 2% to 8% polysucrose, wherein said TFF is performed using a 0.3 to 1 micron filter, thereby preparing a TFF-treated composition comprising 10,000 x 10³ to 20,000 x 10³ platelets/pl in an aqueous medium having less than or equal to 15% plasma protein, and having less than 5.0% microparticles having a radius less than 0.5 pm, by scattering intensity; and freeze drying the TFF-treated composition comprising platelets in the aqueous medium to form a freeze-dried composition comprising platelet derivatives to form the platelet derivative composition, wherein the platelet derivatives in the platelet derivative composition display

197 a potency of at least 1.5 thrombin generation potency units (TGPU) per 10⁶ platelet derivatives, and a reduced propensity to aggregate such that no more than 5% of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets.

20. The process for preparing a platelet derivative composition of 19, wherein the process further comprises after the freeze drying, heating the freeze-dried composition at a temperature in the range of 60°C to 90°C for at least 1 hour to not more than 36 hours to thermally treat the platelet derivatives in the freeze-dried composition to form the platelet derivative composition.

21. The process for preparing a platelet derivative composition of 20, wherein the heating the freeze-dried composition is performed at a temperature in the range of 60°C to 85°C.

22. The process for preparing a platelet derivative composition of 20, wherein the heating the freeze-dried composition is performed at a temperature in the range of 60°C to 80°C.

23. The process for preparing a platelet derivative composition of 19, wherein the TFF-treated composition comprises platelets in the range of 15,000 X 10³ to 20,000 X 10³ platelets/pl.

24. The process for preparing a platelet derivative composition of 19, wherein the aqueous medium has 0.01 to 15% plasma protein.

25. The process for preparing a platelet derivative composition of 19, wherein the aqueous medium has 1 to 5% plasma protein.

26. The process of preparing the platelet derivative composition of 19, wherein the process does not involve contacting the platelets or platelet derivatives with a fixative agent.

27. The platelet derivative composition of any one of claims 1 to 6, wherein the effective dose of the platelet derivatives is in the range of 1.0 X 10⁷ to 1.0 X 10¹²/kg of the subject.

28. The platelet derivative composition of any one of claims 1 to 6, wherein the effective dose of the platelet derivatives is in the range of 1.0 X 10⁷ to 1.0 X 10^u/kg of the subject.

198

29. The platelet derivative composition of any one of claims 1 to 6, wherein the effective dose of the platelet derivatives is in the range of 1.0 X 10⁷ to 1.0 X 10¹⁰/kg of the subject.

30. The platelet derivative composition of any one of claims 1 to 6, wherein the effective dose of the platelet derivatives is in the range of 1.6 x 10⁷ to 1.0 x 10¹⁰/kg of the subject.

31. The platelet derivative composition of any one of claims 1 to 6, wherein the effective dose of the platelet derivatives is in the range of 1.6 x 10⁷to 5.1 x 10⁹/kg of the subject.

32. The platelet derivative composition of any one of claims 1 to 6, wherein the effective dose of the platelet derivatives is in the range of 1.6 x 10⁷ to 3.0 x 10⁹/kg of the subject.

33. The platelet derivative composition of any one of claims 1 to 6, wherein the effective dose of the platelet derivatives is in the range of 1.5 x 10⁹ to LlxlO^lo /kg of the subject.

34. The platelet derivative composition of any one of claims 1 to 6, wherein the effective dose of the platelet derivatives is in the range of 3.0 x 10⁹to 1.0 X 10¹²/kg of the subject.

35. The platelet derivative composition of any one of claims 1 to 6, wherein the effective dose of the platelet derivatives is in the range of 3.0 x 10⁹to 1.0 x 10ⁿ /kg of the subject.

36. The platelet derivative composition of any one of claims 1 to 6, wherein the effective dose of the platelet derivatives is in the range of 3.0 x 10⁹to 1.0 x 10¹⁰/kg of the subject.

37. The platelet derivative composition of any one of claims 1 to 6, wherein the effective dose of the platelet derivatives is in the range of 1.0 x 10¹⁰ to 1.5xlO^lo/kg of the subject.

38. The platelet derivative composition of any one of claims 1 to 6, wherein the effective dose of the platelet derivatives is in the range of 250 to 5000 TGPU/kg of the subject.

39. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the platelet derivatives have an inability to increase expression of a platelet activation marker in the presence of an agonist as compared to the expression of the platelet activation marker in the absence of the agonist.

199

40. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the presence of thrombospondin (TSP) on the surface of the platelet derivatives is at a level that is greater than on the surface of resting platelets.

41. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the presence of von Willebrand factor (vWF) on the surface of the platelet derivatives is at a level that is greater than on the surface of resting platelets.

42. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the platelet derivatives have one or both of: thrombospondin (TSP) on their surface at a level that is at least 50% higher than on the surface of resting platelets; and von Willebrand factor (vWF) on their surface at a level that is at least 50% higher than on the surface of resting platelets.

43. The platelet derivative composition of claim 42, wherein at least 80% of the platelet derivatives are positive for CD42.

44. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein at least 80% of the platelet derivatives are positive for CD42.

45. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein at least 85% of the platelet derivatives in the platelet derivative composition are positive for CD42.

46. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the platelet derivatives are positive for at least one platelet activation marker selected from the group consisting of Annexin V, and CD 62.

200

47. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the platelet derivatives have an inability to increase expression of a platelet activation marker in the presence of an agonist as compared to the expression of the platelet activation marker in the absence of the agonist, and wherein the platelet activation marker is selected from the group consisting of Annexin V, and CD 62.

48. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the platelet derivatives when analyzed for the binding of anti-thrombospondin (TSP) antibody to the platelet derivatives using flow cytometry exhibit at least 2-folds higher mean fluorescent intensity (MFI) in the absence of an agonist as compared to the MFI of binding of anti-TSP antibody to the resting platelets.

49. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the platelet derivatives when analyzed for the binding of anti-von Willebrand factor (vWF) antibody to the platelet derivatives using flow cytometry exhibits at least 1.5-folds higher mean fluorescent intensity (MFI) in the absence of an agonist as compared to the MFI of binding of anti-vWF antibody to the resting platelets.

50. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the platelet derivatives are incapable of retaining more than 50% of lactate dehydrogenase as compared to lactate dehydrogenase retained in fresh platelets, cold stored platelets, or cryopreserved platelets.

51. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the platelet derivatives have at least 50% higher fibrinogen on their surface as compared to resting platelets, or activated platelets.

52. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the platelet derivatives when analyzed for the binding of anti-fibrinogen antibody to the platelet derivatives using flow cytometry exhibit at least 2-fold higher mean fluorescent intensity (MFI) in the absence of an agonist as compared to the MFI of binding of anti-fibrinogen antibody to the lyophilized fixed platelets in the presence of the agonist.

201

53. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the platelet derivatives exhibit coaggregation under conditions comprising the agonist and fresh platelets.

54. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the platelet derivative composition comprises microparticles having a diameter less than 0.5 pm and present in an amount in the range of 0. 1 to 4.9%.

55. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the platelet derivative composition comprises a population of platelet derivatives comprising CD41 -positive platelet derivatives, wherein less than 0.1% of the CD41-positive platelet particles are microparticles having a diameter of less than 0.5pm.

56. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the platelet derivative composition comprises platelet derivatives having a diameter of at least 0.5 pm and microparticles having a diameter less than 0.5 pm, in a ratio of at least 95: 1.

57. The platelet derivative composition of any one of claims 1, 5, or 6 wherein the platelet derivative composition is in a container, and wherein the container is fdled with at least one inert gas.

58. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the platelet derivative composition comprises protein in the range of 0.01-15%.

59. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the platelet derivative composition comprises polysucrose in the range of 45-60% by weight.

60. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the platelet derivative composition comprises trehalose in the range of 20-35% by weight.

202

61. The platelet derivative composition of any of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the agonist is selected from the group consisting of collagen, epinephrine, ristocetin, adenosine di-phosphate, and thrombin receptor associated protein (TRAP).

62. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the platelet derivative composition is: a) negative for HLA Class I antibodies based on a regulatory agency approved test for HLA Class I antibodies; b) negative for HLA Class II antibodies based on a regulatory agency approved test for HLA Class II antibodies; and c) negative for HNA antibodies based on a regulatory agency approved test for HNA antibodies.

63. The platelet derivative composition of claim 6, wherein the indication is Von Willebrand disease, and wherein the indication is not treatable by administering unmodified platelets.

64. The platelet derivative composition of claim 6, wherein the indication is Immune thrombocytopenia, and wherein the indication is not treatable by administering unmodified platelets.

65. The platelet derivative composition of claim 6, wherein the indication is Fetal and neonatal alloimmune thrombocytopenia, and wherein the indication is not treatable by administering unmodified platelets.

66. The platelet derivative composition of claim 6, wherein the indication is intracranial hemorrhage (ICH), and wherein the indication is not treatable by administering unmodified platelets.

67. The platelet derivative composition of claim 6, wherein the indication is traumatic brain injury (TBI), and wherein the indication is not treatable by administering unmodified platelets.

68. A method, comprising rehydrating the platelet derivative composition of any one of claims 1 to 18, or the platelet derivative composition prepared by the process of any one of claims 19 to 26.

203

69. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the platelet derivatives exhibit coaggregation of at least 50% under conditions comprising the agonist and fresh platelets.

70. The platelet derivative composition or the process for preparing of claim 42, wherein the platelet derivatives exhibit co-aggregation of at least 50% under conditions comprising the agonist and fresh platelets.

71. The platelet derivative composition or the process for preparing of claim 43, wherein the platelet derivatives exhibit co-aggregation of at least 50% under conditions comprising the agonist and fresh platelets.

72. The platelet derivative composition or the process for preparing of claim 44, wherein the platelet derivatives exhibit co-aggregation of at least 50% under conditions comprising the agonist and fresh platelets.

73. The platelet derivative composition or the process for preparing of claim 45, wherein the platelet derivatives exhibit co-aggregation of at least 50% under conditions comprising the agonist and fresh platelets.

74. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the platelet derivatives are freeze- dried platelet derivatives.

75. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of claim 20, wherein the platelet derivatives are thermally-treated freeze- dried platelet derivatives.

76. The platelet derivative composition or the process for preparing of claim 71, wherein the platelet derivatives are thermally-treated freeze-dried platelet derivatives.

204

77. The platelet derivative composition of claim 75, wherein the population of platelet derivatives have a reduced propensity to aggregate such that no more than 3% of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets.

78. The platelet derivative composition of any one of claims 1 to 18, or the process for preparing a platelet derivative composition of any one of claims 19 to 26, wherein the population of platelet derivatives have a reduced propensity to aggregate such that no more than 3% of the platelet derivatives in the population aggregate under aggregation conditions comprising an agonist but no platelets.

205