WO2023215560A1 - Tumor cell/immune cell multivalent receptor engager – bio-nanoparticle (timre-bnp) - Google Patents

Abstract

Engineered multivalent bacteriophage are described that can express proteins or protein fragments that can engage a targeted cell cancer cell and also engage and activate an immune cell such as a cytotoxic T-cell and thereby form a cancer cell/ phage/ immune cell complex with a highly responsive immune synapse. Additional proteins or protein fragments can optionally be expressed that can engage more than one type of immune cell, block or activate multiple immune checkpoints, block or activate pathways within the cancer cell, and/or control immunogenicity against the phage by downregulating presentation by antigen presenting cells.

Description

TUMOR CELL/IMMUNE CELL MULTIVALENT RECEPTOR ENGAGER - BIO-NANOPARTICLE (TIMRE-BNP)

Cross Reference to Related Application

[0001 ] This application claims filing benefit of United States Provisional Patent Application Serial No. 63/338,657 having a filing date of May 5, 2022, entitled, “Tumor Cell/lmmune Cell Multivalent Receptor Engager - Bio-Nanoparticle (TIMRE-BNP),” which is incorporated herein by reference in their entirety for all purposes.

Background

[0002] Cancer is a devastating disease in which an individual’s cells acquire a series of genetic mutations and become transformed into a variant cell type which is capable of uncontrolled growth and proliferation as well as metastatic potential - the ability to break away from the tissue of origin and spread to other parts of the body. There are many different types of cancers and these can be categorized by the tissue of origin, by the resulting phenotype and morphological features and/or by the molecular genetic changes that underlie the transformative process. Cancerous cells often grow into tumors of varying sizes and metastasize to other sites within the body. If left unchecked, this uncontrolled growth and metastasis can lead to death due to physical disruption of normal organ function, depletion of nutrients and resources, release of toxic agents, disruption of normal physiology and/or interference with normal cellular communication.

[0003] The mammalian immune system is primarily designed to respond to foreign infectious agents with a mission of search-and-destroy, but not to attack normal host cells. Given that cancer cells are an outgrowth of normal host cells, this presents a challenge for the mounting of a sufficient immune response. To the extent that cancer cells are abnormal they can present anomalies to the immune system that can stimulate an immune response to the cancer. At the same time, because they are derivatives of normal host cells, many of the antigens that they present are those of normal cells to which the immune system has been tolerized. Furthermore, cancer cells often upregulate surface signaling proteins that activate checkpoints in immune cells and downregulate their responses. These are failsafe mechanisms used by normal cells to prevent autoimmune function but can be upregulated in tumor cells. [0004] Cancer immunotherapeutics encompass a broad class of therapeutic agents that mobilize the immune system to attack and kill cancer cells. These agents include a number of different modalities such as: antibodies that can label a cancer cell and mark it for antibody-dependent cellular cytotoxicity (ADCC) or complement dependent cytotoxicity (CDC); vaccines, which can break selftolerance and induce both the cellular and humoral immune arms of the immune system to specifically target the cancer cells; checkpoint inhibitors, which can block the regulatory mechanisms preventing a robust generalized immune response; and CAR T-cells, which are host immune cells that have been genetically reengineered to target cancer cells.

[0005] Recent research has focused on the use of bispecific antibodies to enhance T-cell activation. This so called BiTE (Bispecific T-cell Engager - also known as T-Cell Redirecting Bispecific Antibodies (TRBA)) technology, utilizes engineered bispecific antibodies that combine one single-chain variable fragment (scFv) that binds to a target cancer cell and another scFv that binds to and stimulates T-cell activity. For example, the BiTE can bind to both a tumor specific antigen (TSA) on a cancer cell and to CD3 on a T-cell. In this manner the BiTE brings together the tumor cell and the T-cell and activates the T-cell to kill the tumor cell. An example of a BiTE is the FDA-approved drug, blinatumomab, which binds to CD19 on (benign and malignant) B-cells and CD3 on T-cells resulting in the formation of an immune synapse between the T-cell and the tumor cell, and activation of the T-cell to lyse the tumor cell. This particular BiTE is approved for the treatment of B-cell acute lymphoblastic leukemia (B-cell ALL). A second BiTE, catumaxomab for the treatment of malignant ascites, was approved in 2009 by the EMA, but never by the US FDA. Catumaxomab was not actively marketed after 2014 and was voluntarily discontinued in 2017 due to high immunogenicity rates in humans as it was a fully rodent antibody.

[0006] Unfortunately, BiTEs have suffered from several disadvantages. While the BiTE can engage both the T-cell and the targeted cancer cell, the immune synapse formed is not necessarily equivalent to that of a natural T-cell synapse. Specifically, while the equivalent of signal 1 (the TCR-MHC interaction) is present, signal 2, the costimulatory signal, is often missing. In addition, as BiTEs present each component as a monovalent agent toward both the T-cell and the targeted cancer cell, they may lack sufficient affinity for either or both cells, requiring a significant increase in dose. However, too high a dose can lead to the coating of the two cell types with the agent separately from each other and actually prevent engagement and may induce cytokine release syndrome (CRS). A third issue relates to the activation of immune inhibitory checkpoints in the T-cell upon interaction with a tumor cell. Tumor cells often upregulate ligands that activate such checkpoint pathways in T-cells. Most BiTEs interact with CD3 and thus may recruit both helper T-cells and/or cytotoxic T-cells. Research has suggested that both may be necessary to achieve sufficient and complete killing of all target cells. Further, it may be necessary to engage other immune cells as well, including B- cells and NK cells. While some BiTEs do engage NK cells alone, to date these reagents have been incapable of bringing the entirety of the immune system to bear on the target cancer cells.

[0007] Bacteriophage (or more simply phage) are viruses that infect bacterial cells. These viruses consist of a protein coat which encapsulates a DNA or RNA genome. When phage infect a bacterial cell, they can coopt the host bacterial system to produce large numbers of phage copies and ultimately lyse the bacterial cell, releasing the new phage to the surrounding environment.

[0008] It has been demonstrated that phage can be used to display large numbers of peptide or protein fragments. For example, phage display systems have been used to map the epitopes of antibodies and to identify single chain fragments of antibodies (scFv) that bind to specific antigens. These phage display systems gain their selection power from the ability to display many copies of a protein or protein fragment on the surface of the phage. By way of example, when using bacteriophage , the displayed protein is often engineered as an extension of the phage gpD coat protein. 400 copies of the gpD protein are used by the phage to construct its coat and as such up to 400 copies of the desired protein can be displayed on the phage surface. In the case of bacteriophage X, proteins of up to 300 amino acids can be displayed without disrupting the ability of the phage coat to form. This ability of phage to present on their surfaces large numbers of proteins or protein fragments qualifies them as bio-nanoparticles (BNPs). [0009] What are needed in the art are materials and methods that can more efficiently and successfully enhance response of subject’s immune system against cancer cells.

Summary

[0010] According to one embodiment, disclosed is an engineered multivalent bacteriophage that includes multiple fusion coat proteins. A first fusion coat protein can include an exogenous cancer cell targeting polypeptide directly or indirectly fused to a coat protein of the bacteriophage. This cancer cell targeting polypeptide can include a binding sequence that binds a cancer cell surface antigen. A second fusion coat protein can include an exogenous immune cell targeting polypeptide directly or indirectly fused to a second coat protein of the bacteriophage. This immune cell targeting polypeptide can include a binding sequence that binds an immune cell surface antigen. In embodiments, a bacteriophage can exhibit multiple exogenous cancer cell targeting polypeptides that can bind different epitopes of a cancer cell surface antigen and/or multiple different cancer cell surface antigens. In embodiments, a bacteriophage can exhibit additional exogenous polypeptides that can improve an immune system response against the cancer cell, e.g., providing additional immune cell binding, interacting with one or more costimulatory receptors on immune cells, interacting with one or more checkpoint receptors on immune cells, interacting with one or more immune receptor ligands on cancer cells, etc.

[0011 ] Therapeutic compositions including the engineered multivalent bacteriophage as described in conjunction with a delivery system are also described.

[0012] Also disclosed are methods for forming the multivalent engineered bacteriophage. A method can include transfecting a bacterial cell with one or more expression plasmids and also infecting the bacterial cell with a phage. The expression plasmid(s) can include a first hybrid nucleic acid sequence that encodes the first fusion coat protein designed for targeting the bacteriophage to a cancer cell and a second hybrid nucleic acid sequence that encodes the second fusion coat protein designed for targeting the bacteriophage to an immune system cell. The expression plasmid can also include regulatory sequences such that following the transfection, the fusion coat proteins are transiently expressed by the bacterial cell. Upon the infection and the transfection, an engineered phage can be produced by the bacterial cell that includes multiple copies of both of the fusion coat proteins. The method can form a multivalent phage with high affinity and binding avidity for the targeted cancer cells as well as immune system cells and can create a highly effective immune synapse between cancer cells and immune system cells.

Brief Description of the Figures

[0013] A full and enabling disclosure of the present subject matter, including the best mode thereof to one of ordinary skill in the art, is set forth more particularly in the remainder of the specification, including reference to FIG. 1 , which schematically illustrates one embodiment of a multivalent, multiplexed immunotherapeutic bacteriophage as described herein.

Detailed Description

[0014] Reference will now be made in detail to various embodiments of the disclosed subject matter, one or more examples of which are set forth below. Each embodiment is provided by way of explanation of the subject matter, not limitation thereof. In fact, it will be apparent to those skilled in the art that various modifications and variations may be made in the present disclosure without departing from the scope or spirit of the subject matter. For instance, features illustrated or described as part of one embodiment, may be used in another embodiment to yield a still further embodiment. Moreover, it is noted that all US patent and published patent applications mentioned herein are incorporated by reference thereto.

[0015] In general, the present disclosure is directed to engineered multivalent phage that can be utilized to encourage and enhance the host immune response to cancer cells. The engineered phage can function as bio-nanoparticles (BNP) with the presentation of two or more proteins or protein fragments that can engage a targeted cell cancer cell and also engage and activate an immune cell such as a cytotoxic T-cell. Through inclusion of additional proteins or protein fragments, disclosed phage can provide one or more additional functions including, without limitation, engage more than one type of immune cell, block or activate multiple immune checkpoints preventing downregulation of an immune cell, block or activate pathways within the cancer cell to enhance its susceptibility to killing by an immune effector cell, and/or control immunogenicity against the phage by downregulating presentation by antigen presenting cells (APCs). As such, disclosed multivalent engineered phage are synonymously referred to herein as Tumor cell I Immune cell Multivalent Receptor Engager - Bio-Nanoparticles (TIMRE-BNPs).

[0016] Disclosed engineered bacteriophage can display high copy numbers of a targeting polypeptide that can bind a surface antigen of a targeted cancer cell, and as such can achieve high affinity/avidity for the targeted cancer cell. Disclosed materials can also display high copy numbers of one or more immune system targeting/activation components and as such can provide a high functioning immune synapse between immune system components and the targeted cancer cell. This can provide for increased efficiency of a cancer immunotherapy. Moreover, by supplying multiple different immune system components in high copy number, more than one approach for cancer cell recognition and clearance by the immune system can be delivered.

[0017] Beneficially, a single phage can include multiple copies of both a cancer cell targeting polypeptide and an immune cell targeting polypeptide as well as, in some embodiments, multiple different cancer cell targeting polypeptides and/or multiple different and immune system related polypeptides. A targeting polypeptide can be directly or indirectly fused to coat proteins of the phage. In some embodiments multiple targeting polypeptides of a single phage can be directly or indirectly bonded to one another, for instance as multiple targeting polypeptides directly or indirectly (e.g., via linking polypeptides) bonded to a terminal end of a single phage coat protein. Such capabilities can further increase the specificity of the engineered phage for the targeted cancer cell and by targeting two or more low abundant antigens with inclusion of two or more different targeting polypeptides can increase the available number of target sites.

[0018] Due to the large number of coat proteins available on a phage, the engineered phage can be further supplied with polypeptides that can provide other uses, e.g., labeling, control of immunogenicity against the phage during use by downregulating presentation by antigen presenting cells (APCs), or any other useful purpose. [0019] In addition to the above advantages, disclosed engineered phage can also be free of nucleic acid encoding the exogenous polypeptides, and as such, there is no concern of transfer of foreign DNA or RNA to a host, which can be particularly beneficial in cancer immunotherapy. In some embodiments, the DNA and/or RNA of the phage genome encased within the capsid of the engineered phage, which will still be present in the bacterially produced product, can include a modification from wild-type phage, e.g., a stop codon that can prevent further replication of the phage following production, an insert to control immunogenicity, etc.

[0020] The use of phage as BNPs as compared to other synthetic nanoparticles or bio-nanoparticles is especially advantageous. Phage are simple to genetically engineer and are easy to purify. Furthermore, phage can be produced at extremely high yield in readily available biofermenters. As such, the development and manufacturing processes can be rapid and highly cost-effective. In vivo, phage are known to have long half-lives and their size allows for easy tissue penetration. In general, phage have demonstrated only low levels of immunogenicity in mammals, including humans, likely due to early exposure and partial acquired immune tolerance due to the abundance of phage in the natural environment. Moreover, recent developments in phage formation have provided phage as potential starting materials for disclosed TIMRE-BNP that are even less immunogenic that previously known phage due to genetic modification of certain phage proteins (e.g. Merril CR, et al. 1996 Proc. Natl. Acad. Sci. USA, 93:3188- 92), contain a conditional expression of a wildtype phage protein (e.g. phage A gpD as in Nicastro J, et al. 2013 Appl Microbiol Biotechnol 97:7791-804) and/or incapable of further reproduction, which can be advantageous in some embodiments. Additionally, as the phage are BNP, they can optionally be irradiated prior to use to prevent any potential infectivity to a subject.

[0021] Phage that may be modified to provide disclosed TIMRE-BNP may be any bacteriophage known to those skilled in the art, including but not limited to A, M13, T4, T7, and cpX174. The coat proteins to which the exogenous polypeptides are fused in forming a fused coat protein will depend on the type of phage employed as well as the number of exogenous polypeptides desired for each phage. For A phage, the gpD, gpE or gpC proteins can be used, with over 400 copies of each of the gpD and gpE in each phage. For M13 phage, the pVIII, pill, pVI, pVII or pIX proteins can be used. For T4 phage, the gp23 or gp24 proteins can be used and for T7 phage the gp1 OA or gp1 OB proteins can be used. For phage cpX174, the gpF or gpG proteins can be used. The numbers of copies of each of these proteins within the specific phage type varies from tens of copies to hundreds of copies, as is known. For example, bacteriophage A have two major capsid proteins, gpD and gpE, which are incorporated in over 400 copies each in the phage.

[0022] FIG. 1 schematically illustrates one embodiment of an engineered multivalent bacteriophage designed for cancer immunotherapy as described herein. As illustrated, a bacteriophage can include typical bacteriophage components including tail fiber 10, spikes 12, and a sheath 14. A collar 16 typically separates the sheath 14 from the capsid head 18, which encases the bacteriophage endogenous RNA or DNA genome 20. The capsid head 18 is formed from a plurality of coat proteins, e.g., gpD, gpE and gpC coat protein in the case of bacteriophage A. Multivalent bacteriophage as disclosed herein can include two or more different fusion coat proteins 22, 24 in the capsid head 18 that include an exogenous polypeptide at a terminal end of a coat protein, which can be either or both of an N-terminus or C-terminus of the coat protein. One of the fusion coat proteins 22 can include an exogenous polypeptide that incorporates a cancer cell targeting polypeptide configured to specifically bind a cancer cell surface antigen. Another of the fusion coat proteins 24 can include an exogenous polypeptide incorporates an immune cell targeting polypeptide configured to specifically bind and an immune cell and stimulate an immune response to the cancer cell upon formation of a cancer cell/ phage/ immune cell complex.

[0023] As utilized herein, the term “exogenous” refers to a material that originates external to and is not found as a component of either the phage or the bacterial cell that are used to produce the TIMRE-BNP. As utilized herein, the term “polypeptide” generally refers to a polymeric molecule including two or more amino acid residues, which can include natural and synthetic amino acids as well as combinations thereof and includes proteins as well as fragments. As utilized herein, the term "fragment" generally refers to a continuous part of a full-length protein, with or without mutations, which is separate from and not in the context of a full length protein. A fragment may be a structural/topographical or functional subunit of a full length protein. In some embodiments, a fragment can have an amino acid sequence of about 15 or more amino acids, or about 20 or more amino acids of the parent full-length surface protein.

[0024] The ability to display large copy numbers of the different exogenous polypeptides on the surface of a phage allows for improved effectiveness. Simply put, when a cancer cell, an immune cell, and a TIMRE-BNP interact and form a complex, the existence of multiple binding points can greatly enhance the overall strength of the interaction (avidity). By way of example, when using bacteriophage , the displayed exogenous cancer cell targeting polypeptide can be engineered as an extension of the phage gpD coat protein and the immune cell targeting polypeptide can be an extension of the gpE coat protein. 400 copies of both the gpD and gpE proteins are used by the phage to construct its coat and as such, by utilizing fusion gpD proteins to carry the cancer cell targeting polypeptide and fusion gpE proteins to carry the immune cell targeting polypeptide, up to 400 copies of the cancer cell targeting polypeptide and up to 400 copies of the immune cell targeting polypeptide can be displayed on the phage surface, which can ensure a high likelihood of formation of the immunotherapy complex. Moreover, an exogenous polypeptide of a fusion coat protein can be quite large without disrupting the ability of the phage to form. For instance, in the case of bacteriophage X, relatively large polypeptides (300 amino acids or more) or multiple smaller polypeptides that are the same or different from one another can be ligated to one another and included in a single fusion protein without disrupting the ability of the phage coat to form.

[0025] In general, exogenous polypeptide sequences chosen for inclusion in a fusion coat protein for use as a cancer cell targeting agent, an immune cell targeting agent, an immune system stimulant, a linker, or any other use, may be derived from any source and can include complete proteins, protein fragments, mutants, or homologues thereof. In one embodiment a multivalent bacteriophage can be engineered that can include multiple different fragments (or homologues thereof) of a single protein. For instance, when the natural protein of interest is large and incorporation of the entire protein sequence in a single fusion coat protein could interfere with bacteriophage formation, desired components of the protein can be included on the phage as separate segments, e.g., a first segment that can provide binding to and stimulation of a targeted immune cell and a second segment that can provide a desired co-stimulation or other support of the immune response. As utilized herein, the term "homologue" generally refers to a nucleotide or polypeptide sequence that differs from a reference sequence by modification(s) that do not affect the overall functioning of the sequence. For example, when considering polypeptide sequences, homologues include polypeptides having substitution of one amino acid at a given position in the sequence for another amino acid of the same class (e.g., amino acids that share characteristics of hydrophobicity, charge, pK or other conformational or chemical properties, e.g., valine for leucine, arginine for lysine, etc.). Homologues can include one or more substitutions, deletions, or insertions, located at positions of the sequence that do not alter the conformation or folding of a polypeptide to the extent that the biological activity of the polypeptide is destroyed. Examples of possible homologues include polypeptide sequences and nucleic acids encoding polypeptide sequences that include substitution of one non-polar (hydrophobic) residue such as isoleucine, valine, leucine or methionine for another; the substitution of one polar (hydrophilic) residue for another such as between arginine and lysine, between glutamine and asparagine, or between threonine and serine; the substitution of one basic residue such as lysine, arginine or histidine for another; the substitution of one acidic residue, such as aspartic acid or glutamic acid for the another; or the use of a chemically derivatized residue in place of a non-derivatized residue, as long as the homolog displays substantially similar biological activity to the reference sequence.

[0026] Exogenous polypeptides displayed on a phage surface may be derived from an antibody that specifically recognizes and binds one or more epitopes of a surface antigen of the targeted cell. These displayed polypeptides may correspond to antibodies or any derivative thereof including but not limited to single-chain antibodies (scFv) and/or nanobodies (VH or VHH sequences). The term antibodies and antibody fragments as utilized herein is intended to incorporate all antibody types derived from any species including but not limited to humans, rodents, livestock, camelids, fowl, etc. The sequences of these antibodies and/or antibody fragments may be modified such that potential human B and/or T-cell epitopes have been mutated to reduce potential immunogenicity to non-cancerous cells as is known to one skilled in the art.

[0027] The binding partner of a targeting polypeptide of a TIMRE-BNP can generally be surface expressed on the targeted cell. Furthermore, there can generally be suitable amounts of the binding partner expressed on the cell surface in order to ensure formation of the cancer cell/ phage/ immune cell complex. However, in some embodiments, a targeted cell can include a lesser number of a single binding partner, and the TIMRE-BNP can include multiple different targeting polypeptides, for instance to avoid over-loading a cell type with the multivalent phage and inadvertently preventing formation of the complex. In any case, the exogenous cancer cell and immune cell targeting polypeptides of the TIMRE-BNP, e.g., an antibody or derivative thereof (single chain antibody, scFv, etc.), can afford specificity to the targeted binding partner of a cell and can bind with a relatively high affinity to each type of cell, so as to form a complex with the TIMRE-BNP upon the binding.

[0028] In one embodiment, different targeting polypeptides of a bacteriophage can specifically bind a single protein target, e g., different binding sequences that specifically bind different epitopes of a single surface protein of a cancer cell or an immune cell. For example, a first exogenous polypeptide can include a binding sequence specific for a first epitope of a cancer cell surface protein and a second, different exogenous polypeptide can include a second, different binding sequence specific for a second epitope of the same surface protein. Likewise, a first exogenous polypeptide can include a binding sequence specific for a first epitope of an immune cell surface protein and a second, different exogenous polypeptide can include a second, different binding sequence specific for a second epitope of the same surface protein of the immune cell. In one embodiment, different exogenous targeting polypeptides of a bacteriophage can specifically bind different surface proteins of the same cell type, e.g., a first targeting polypeptide binding sequence can bind a first surface protein and a second targeting polypeptide binding sequence can bind a different surface protein of the same cell. Of course, any combination of cancer cell targeting polypeptides and immune cell targeting polypeptides are encompassed herein as well. Moreover, a single exogenous targeting polypeptide can include multiple binding sequences, which can be the same or different from one another.

[0029] Cancer cells that can be targeted by disclosed materials are not particularly limited, and can include both solid and hematological cancers. Exemplary cancer types that can be targeted by disclosed TIMRE-BNPs can include, without limitation, prostate cancers, multiple myeloma, pancreatic cancers, liver cancers, bile duct cancers, brain cancers, breast cancers, colon cancers, ovarian cancers, lung cancers, leukemias, etc.

[0030] Cancer cell targeting polypeptides can include antibodies or antibody fragments (e.g. scFv) that are known to bind to a tumor specific surface antigen such as, and without limitation to, aspartyl p-hydroxylase (ASPH), prostate specific membrane antigen (PSMA), B-cell maturation antigen (BCMA), melanoma associated antigen (MAGE), NY-ESO1 , carcinoembroyonic antigen (CEA), human epidermal growth factor receptor 2 (HER2), CD33, nectin-4, CD30, DCD22, CD79b, TROP2, etc. However, while a tumor specific surface antigen can be targeted in one embodiment, any tumor associated surface antigen can be targeted by disclosed TI RE-BNP.

[0031 ] PSMA and BCMA are well known tumor targets representing both a solid tumor antigen and a hematological cancer antigen. Clinical applications of these targets include treatment of recurrent prostate cancer and multiple myeloma, respectively. ASPH is a low abundant tumor antigen with broad tumor expression across 20 different cancer types including both solid and hematological cancers. ASPH has been previously used as a target for an anti-cancer vaccine that entered human phase II clinical trials and has also been demonstrated as a promising target for an antibody-drug conjugate (ADC) approach in patient-derived xenograft (PDX) models of pancreatic cancer. ASPH is an enzyme that hydroxylates aspartate or asparagine residues present in EGF-like domains of certain proteins including NOTCH, JAGGED, vimentin, ADAM10/17, and ADAM12/15. The normal function of the enzyme appears to be regulation of signaling pathways during embryonic development and in the case of the NOTCH/JAGGED interaction, the hydroxylation of the EGF domains results in increased downstream signaling. In cancer cells, ASPH has been shown to be translocated to the cellular surface from where it is normally located. This surface re-localization is noteworthy because it allows for, and in fact advocates the use of, disclosed immunotherapies that access the cell surface.

[0032] Antibodies to these as well as other cell surface antigens are known and available in the art. By way of example, known antibody sequences that bind ASPH include, without limitation, FB50, a mouse monoclonal antibody that binds to the membrane proximal domain of ASPH; 622, a fully human antibody targeting the catalytic domain of ASPH; and 15c7, a murine mAb that binds the catalytic domain of ASPH, any of which can be utilized in development of a TIMRE-BNP as disclosed. PSMA antibodies as disclosed in US Pat. App. Pub. No. 2023/0131727 to Goldberg et al., which is incorporated herein by reference thereto, can be utilized in some embodiments. In some embodiments, antibodies or fragments thereof as may be incorporated as targeting polypeptides can include IgG isotype monoclonal antibodies including, without limitation to, chimeric I gG1 , human or humanized IgGlK, and humanized lgG4K, which have been utilized in previously described ADCs.

[0033] Immune cell targeting polypeptides of an engineered phage can include a binding sequence specific for an immune cell surface antigen. In general, the immune cell targeted by a bacteriophage fusion coat protein can be an effector immune cell, which can actively respond upon formation of the immune synapse with the cancer cell and thus activate an immune response against the cancer cell, e.g., a cytotoxic response that can destroy the cancer cell via ADCC modality, CDC modality, or any other approach or combination thereof.

[0034] In one embodiment, an immune cell targeting polypeptide can include a binding sequence specific for a cytotoxic T-cell surface antigen, e.g., CD4⁺ T-cell surface antigens, CD8⁺ T-cell surface antigens, etc. For instance, the immune cell targeting polypeptide can include a binding sequence of an antibody or antibody fragment, e.g., an scFv, that can bind a T-cell surface protein selected from, but not limited to, CD3, CD4, CD8, non-polymorphic MHC class l-related protein MR1 , CD 25, etc.

[0035] Of course, the targeted immune cell of a TIMRE-BNP is not limited to T- cells. Immune cells targeted by disclosed TIMRE-BNP can include one or more immune cells of a host, in addition to or alternative to targeting a T-cell. For instance, in one embodiment, a TIMRE-BNP can include immune cell targeting polypeptide(s) including one or more binding sequences directed to helper T-cells (TH1 helper cells, TH2 helper cells), B-cells, NK cells, etc.

[0036] In those embodiments in which a fusion protein of the engineered bacteriophage includes a binding sequence configured to bind a B-cell, the targeted surface protein engaged might include, but is not limited to CD19, CD20, etc. In those embodiments in which a fusion protein of the engineered bacteriophage includes a binding sequence configured to bind an NK cell the surface protein engaged might include but is not limited to NKp46, CD16, etc. As previously mentioned, a TIMRE-BNP can in some embodiments express multiple binding sequences configured to engage multiple epitopes of a single immune cell surface protein, multiple different immune cell surface proteins, and/or multiple different immune cell types.

[0037] Binding sequences configured to bind a targeted immune cell with high affinity (e.g., T-cell binding, B-cell binding, NK cell binding, etc.) have been described, any of which can be utilized as exogenous polypeptide binding sequences of disclosed TIMRE-BNP. Examples of binding sequences as may be incorporated in disclosed TIMRE-BNP have been described as components of chimeric proteins, superantigens, etc., which include at least one sequence capable of binding and activating an immune cell. Exemplary binding sequences can be found, for example, in U.S. Pat. Nos. 5,858,363; 6,197,299; 6,713,284; 6,692,746; 7,226,595; 7,226,601 ; 7,279,291 ; 7,094,603; 7,087,235; 8,329,181 ; 9,273,141 ; 11 ,623,958; and US Pat. App. Pub. No. 2023/0109275; all of which are incorporated herein by reference thereto.

[0038] In some embodiments, a TIMRE-BNP can include one or more additional exogenous polypeptides that can enhance the immune response against the targeted cancer cell. Such additional components can be configured to further stimulate specific immune effector cell functions (e.g., costimulatory molecules), to block inhibitory pathways in immune effector cells, or any other function that can enhance the immune response generated by use of the TIMRE-BNP. By way of example, an engineered phage can include as components of one or more fusion coat proteins a first scFv or protein that binds to a surface antigen on a targeted cancer cell, a second scFv or protein that binds to a surface marker found on an immune effector cell, and one or more additional scFv or protein(s) that serve to enhance the immune response generated by the TIMRE-BNP. For example a TIMRE-BNP can include an exogenous polypeptide sequence that can block an immune suppressive checkpoint by engaging either a ligand on the tumor cell or a receptor on an immune effector cell.

[0039] Tumor cell ligands that can be targeted for such an effect can include, without limitation, PD-L1 , PD-L2, B7-1 , B7-2, MHC-I, MHC-II, galectin-9, as well as any combination thereof. Binding sequences specific for such ligands are known in the art, see, e.g., US Pat. No. 10,889,648; US Pat. No. 8,552,154; US Pat. App. Pub. No. 2002/0176855; US Pat. No. 6,972,125; US Pat. No. 8,242,398, and US Pat. No. 10,899,838; all of which being incorporated herein by reference thereto. [0040] Immune effector cell receptors that can be targeted for such an effect can include, without limitation, PD-1 , CTLA-4, LAG-3, TIM-3, VISTA, BTLA, as well as any combination thereof. Binding sequences specific for such receptors are known in the art, see, e.g., US Pat. No. 11 ,517,623; US Pat. App. Pub. No.

2022/0064303; US Pat. No. 11 ,285,207; US Pat. No. 10,287,352; US Pat. App. Pub. No. 2021/0038697; US Pat. No. 10,961 ,297; all of which being incorporated herein by reference thereto.

[0041] In one embodiment, a TIMRE-BNP can include an exogenous polypeptide sequence that can stimulate an immune activating checkpoint by engaging a receptor on the immune effector cell such as, and without limitation to, 4-1 BB, CD28, IGOS, KIRs, GITR, or any combination thereof. Binding sequences specific for such receptors are known in the art, see, e.g., US Pat. No. 10,875,921 ; US Pat. No. 11 ,530,268; US Pat. No. 8,168,759; US Pat. No. 9,957,323; US Pat. No. 9,193,789; US Pat. No. 10,577,417; US Pat. App. Pub. No. 2020/0079861 ; US Pat. No. 9,701 ,751 ; all of which being incorporated herein by reference thereto. [0042] As discussed previously, due to the number of coat proteins available for modification as described, a TIMRE-BNP can include multiple copies of multiple different sequences, including cancer cell targeting sequences, immune cell targeting sequences, and any number of immune response enhancement sequences.

[0043] A polypeptide linker may be included on the TIMRE-BNP as an extension of a phage coat protein in a fusion coat protein, e.g., linking the coat protein to a fused targeting polypeptide or an immune response enhancement polypeptide and/or between exogenous polypeptide segments of a single fusion coat protein. The length of a polypeptide linker is not critical. For example a polypeptide linker can be from about 5 to about 50 amino acids long, such as from about 10 to about 40 amino acids long, such as from about 10 to about 35 amino acids long, such as from about 10 to about 30 amino acids long, such as from about 10 to about 25 amino acids long, such as from about 10 to about 20 amino acids long, such as from about 15 to about 20 amino acids long, in some embodiments.

[0044] Amino acid residues of a polypeptide linker component can include those occurring naturally as well as minor amino acids and non-naturally occurring amino acid analogs, such as citrulline. Exemplary amino acids that may be included in a linker are Gly, Ser Pro, Thr, Glu, Lys, Arg, lie, Leu, His and The. Exemplary linkers that may be used include Gly rich linkers, Gly and Ser containing linkers, Gly and Ala containing linkers, Ala and Ser containing linkers, and other flexible linkers. In some embodiments, a polypeptide linker can include a dipeptide, a tripeptide, a tetrapeptide or a pentapeptide. Exemplary dipeptides include valine-citrulline (vc orval-cit), alanine-phenylalanine (af or alaphe). Exemplary tripeptides include: glycine-valine-citrulline (gly-val-cit) and glycine- glycine-glycine (gly-gly-gly). In one embodiment, a polypeptide linker can include portions of an immunoglobulin hinge area, CL or CH1 derived from any immunoglobulin heavy or light chain isotype. Exemplary polypeptides as may be incorporated in an engineered phage as described herein include those described in US Pat. App. Pub. No. 2023/0125881 to Grinstaff et al., and US Pat. App. Pub. No. 2023/0126689 to Schnabel et al., which are incorporated herein by reference thereto.

[0045] Due to the large number of coat proteins of a phage, all of which can be substituted in some embodiments for fusion coat proteins in forming disclosed TIMRE-BNP, an engineered phage can be designed to include additional beneficial materials at the surface, in addition to the targeting and immunotherapy polypeptides.

[0046] In one embodiment, a TIMRE-BNP can include at the surface via a fusion coat protein a material that can decrease the chances of an immunogenic response by a subject. By way of example, a TIMRE-BNP can include an IL-10 protein on the surface of the phage. IL-10 is known to suppress antigen presentation by professional antigen presenting cells (APCs) including dendritic cells and macrophages. By supplying IL-10 on the phage, rather than systemically, only APCs that are likely to endocytose and present phage derived proteins can be suppressed rather than all APC function.

[0047] In some embodiments, an imaging agent or other detectable marked can be included on a TIMRE-BNP. For example, a fluorescent protein such as green fluorescent protein (GFP) can be expressed on a phage as an extension of a coat protein for use as a marker.

[0048] In some embodiments a radioactive metal can be incorporated on a TIMRE-BNP as an imaging agent or detectable label. Radionuclides used to radiolabel a phage can include, but are not limited to, ¹¹C, ¹³N, ¹⁵O, ¹⁸F,⁶⁴Cu, ⁶⁷Cu, ⁶⁷Ga, ⁶⁸Ga, ^{81 m}Kr, ⁸²Ru, "Tc, ¹¹¹ Ir, ¹²³l, ¹²⁴l, ¹²⁵l, ¹³¹l, ¹³³Xe, ²⁰¹Th, ⁸⁹Zr, ⁹⁰Y, ¹⁷⁷Lu, ²¹¹At, ²¹²Pb, ²¹²Bi, ²¹³Bi, ¹³⁴Ce, and ²²⁵Ac, or any combination thereof. Such radioactive materials can be bonded to the phage via a linking agent, such as those described previously, generally in conjunction with a chelator.

[0049] A chelator can generally include a macrocyclic chelating moiety that can bond a linking agent of an exogenous polypeptide. Examples of macrocyclic chelating moieties include, without limitation, 1 ,4,7,10-tetraazacyclododecane- 1 ,4,7, 10, tetraacetic acid (DOTA), S-2-(4-isothiocyanatobenzyl)-1 ,4,7- triazacyclononane-1 ,4,7-triacetic acid (NOTA), 1 ,4,8,11-tetraazacyclodocedan- 1 ,4,8,11 -tetraacetic acid (TETA), 3,6,9,15-tetraazabicyclo[9.3.1]-pentadeca- 1 (15),11 ,13-triene-4-(S)-(4-isothiocyanatobenzyl)-3,6,9-triacetic acid (PCTA), 5-S- (4-aminobenzyl)-1-oxa-4,7,10-triazacyclododecane-4,7,10-tris(acetic acid) (DO3A), or a derivative thereof. Additional examples of chelators suitable for use in accordance with the present invention are described in US Pat. Nos. 11 ,554,182 and 1 1 ,279698, which are incorporated by reference herein. In those embodiments in which the TIMRE-BNP includes multiple different chelators, any combination of chelators can be utilized.

[0050] In one embodiment, and in order to promote proper folding and disulfide bond formation of proteinaceous components, modified coat proteins of the engineered phage can co-express the yeast ervl p protein (FAD-linked sulfhydryl oxidase) and mammalian protein disulfide isomerase (PDI), which together have been demonstrated to afford mammalian-like disulfide bond formation in proteins expressed in bacteria. The versatility of this design makes it amenable to the incorporation of a large number of binding proteins onto a single phage while retaining the high copy number of each displayed protein.

[0051] In forming the engineered phage, a bacterial production system can be utilized in which the bacteria of choice can produce the phage that include multiple fusion coat proteins. In some embodiments, the coat protein of the starting phage may be silenced such that all coat protein of the product phage are fusion coat proteins. Alternatively, a portion of the native coat protein of the starting phage may be maintained to allow better separation/distribution of the fusion coat protein copies on the phage surface.

[0052] The engineered phage can be manufactured in bacterial cultures that can be grown at large scale in standard bio-fermenters. Expression plasmids, produced by recombinant DNA technology and encoding a phage fusion coat protein with an added extension encoding the desired exogenous polypeptide is transfected into the bacterial cells prior to infection with phage. By supplying multiple plasmids encoding different protein extensions added to the phage coat sequence or multiple copies of the gene encoding the phage coat protein with different added extensions encoding varying proteins of interest on the same plasmid, phage can be produced with the different proteins displayed on their coat. [0053] Expression of the fusion coat proteins is achieved through stable transfection of bacteria with expression plasmids containing the sequences for the altered coat proteins prior to infection of the same bacteria with the starting phage. Specifically, a DNA sequence encoding a phage coat protein is ligated to a DNA sequence encoding the cancer cell targeting polypeptide such that the latter sequence is in frame with the former. DNA encoding a short linker sequence may be placed between the two sequences if desired. In addition, a DNA sequence encoding the same or a different phage coat protein is ligated to a DNA sequence encoding the immune cell targeting polypeptide such that the two are in frame with one another, optionally in conjunction with a short linker sequence. In those embodiments in which additional targeting or immune system functional polypeptides are to be expressed on the phage surface, additional sequences can likewise be formulated. [0054] The hybrid nucleic acid (e.g., DNA) sequences are placed into one or more bacterial expression plasmids under the control of a bacterial expression promoter. A single bacterial expression plasmid can be utilized for both the cancer cell targeting and immune cell targeting hybrid DNA sequences or each hybrid DNA sequence can be placed into a separate bacterial expression plasmid. In an embodiment in which a TIMRE-BNP is formed that includes multiple targeting polypeptides and/or other immune system functional polypeptides, any combination thereof can be utilized, e.g., one or more bacterial expression plasmids that contain a single hybrid DNA sequence as well as one or more bacterial expression plasmids that contain multiple different hybrid DNA sequences. Moreover, variant copies of a hybrid DNA sequence encoding the different protein extensions desired may be expressed within the same or different expression plasmids. Transient expression systems have been used as tools of recombinant technology for many years and as such is not described in detail herein. By way of example and without limitation, suitable transient expression systems can include the pETDuet™ family of vectors from Novagen/EMD Millipore. [0055] Promoters used for the expression plasmid(s) can be the same or different in different expression plasmids. Promoters can be an inducible promoter, a copy of the native phage promoter or any promoter deemed appropriate by one skilled in the art. When using different plasmids, it is generally recommended to use different selection markers to ensure that selected bacteria have incorporated all plasmid types. It is also possible for the different plasmids to use different strength promoters, thus allowing for the coat proteins with different extensions to be produced at varying levels which should allow for incorporation into the phage at different ratios. The plasmids are transfected into host bacterial cells that are infectable by the chosen phage. Host bacteria harboring the expression plasmids are subsequently infected with the starting phage and grown until lysis of the bacteria. If an inducible promoter is used in the expression plasmids, the inducing agent must be supplied during phage infection. Once bacterial cell lysis has occurred the product engineered phage can be purified and characterized using standard techniques. It should be noted that loss of infectivity by the modified phage is not a problem for the use of these TIMRE-BNPs and in fact may be considered advantageous. [0056] By way of example, when forming an engineered A phage, an expression plasmid can include DNA encoding one or more fusion coat proteins based on one or more of the gpD, gpE or gpC coat proteins in conjunction with the encoding of one or more exogenous polypeptides in any combination. For example DNA of one or more plasmids can encode a cancer cell targeting polypeptide in conjunction with a gpD coat protein, as well an immune cell targeting polypeptide and/or a polypeptide linker in conjunction with a gpD coat protein. In another embodiment, DNA of one or more plasmids can encode a cancer cell targeting polypeptide in conjunction with a gpD coat protein as well as and immune cell targeting and/or a polypeptide linker in conjunction with a different, e.g., gpE, coat protein, or any combination thereof.

[0057] If an engineered M13 phage is to be formed, one or more of the pVIII, pill, pVI, pVII or pIX proteins can generally be encoded in an expression plasmid in conjunction the exogenous polypeptides. Similarly, the gp23 and/or gp24 proteins can generally be encoded when forming an engineered T4 bacteriophage and the gp10A and/or gp1 OB proteins can be encoded in an expression plasmid when forming an engineered T7 phage. For phage cpX174 the gpF and/or gpG proteins can generally be encoded in conjunction with the exogenous polypeptides.

[0058] When using different expression plasmids to carry different fusion coat protein DNA, the regulatory components of the expression plasmids can be the same or differ from one another. For instance, in one embodiment, different expression plasmids can be essentially the same as one another, other than the fusion coat protein DNA sequences. In one embodiment, different selection markers can be incorporated on the different expression plasmids, which can be used to ensure that selected production bacteria have incorporated all plasmid types. In one embodiment, different plasmids or different expression components of a single plasmid can incorporate different promotors driving expression of the fusion coat proteins, for instance, different strength promoters, thus allowing for the fusion coat proteins with different exogenous polypeptide extensions to be produced at varying levels which can also allow for incorporation of the different fusion coat proteins into an engineered phage at different ratios.

[0059] The host bacterial cell can be any suitable type that can be transfected by the plasm id(s) and is also infectable by the phage that is to be the basis for the engineered phage product. For instance, when forming an engineered bacteriophage A, the host bacterial cell can be an E. coli and an E. coli can thus be transfected with the expression plasmid(s) according to standard transfection practice. Suitable bacterial hosts for phage infection are known to those in the art. Depending upon the transfection/expression system utilized, additional components as necessary can be supplied to the bacterial host. For instance, if an inducible promoter is incorporated in the expression plasmid(s), the inducing agent can also be supplied to the bacterial host during phage infection.

[0060] Upon transfection and infection, the bacterial host can produce the engineered bacteriophage that incorporate the fusion coat proteins. Beneficially, because the fusion coat proteins are produced from plasm id(s) transiently expressed in the bacteria during phage production, the DNA encoding the exogenous polypeptide is not incorporated into the phage.

[0061 ] The amount of fusion coat proteins incorporated into an engineered bacteriophage can be controlled in one embodiment, such as through selection of the promoter strength of an expression plasmid. Such an approach can be used to control relative amount of different fusion coat protein in a bacteriophage as well as relative amount of the starting, e.g., wild type, coat protein vs. the fusion coat protein. In such an embodiment, the phage coat protein upon which the fusion coat protein is based can be maintained to a controlled extent on the engineered phage. Thus, the engineered phage can include a portion of the coat protein lacking any fused exogenous polypeptide in addition to the fused coat protein. [0062] In one embodiment, the bacterial cell can be infected with a knock-out phage in which the wild-type coat protein expression has been silenced or deleted. In this case, all of the coat protein of the type incorporated in the expression plasmid (e.g., all gpD coat protein of a bacteriophage A) can be present in the expressed engineered phage as fusion coat protein.

[0063] In one embodiment, the bacterial cell can be infected with a phage that has been genetically altered as compared to a wild-type phage. For instance, the starting phage that infect the bacteria can be modified to include a stop codon that prevents formation of a coat protein. In such a case, the bacterial host can include a genetic modification to avoid that stop codon, but the product engineered phage can still include the stop codon and as such, will be less infective during use. In another embodiment, the phage can be genetically altered as compared to a wildtype phage so as to be less immunogenic in the intended use, e.g., to a subject to be treated by use of the TIMRE-BNP.

[0064] Following lysis, engineered bacteriophage may be purified by any number of methods known to those skilled in the art for bacteriophage purification. These methods include, but are not limited to polyethylene glycol (PEG) precipitation, tangential flow filtration, affinity chromatography, etc. By way of example, phage can be isolated via a series of steps involving centrifugation of lysed cultures, tangential flow filtration for concentration and buffer exchange, ethanol and triton X-114 precipitation to remove endotoxin followed by additional filtration, concentration and washing of the material. Engineered bacteriophage characterized by standard methods known to those skilled in the art. Phage yields can be on the order of 5x10¹³ - 5x10¹⁴ particles/liter.

[0065] Product characterization methods can include, without limitation:

Purity: pH; potentiometric determination; visual appearance, sterility; spectrophotometry and ELISA to determine level of chemical impurities. The goal is to achieve >95% purity.

Microbial contaminants: Limulus Amebocyte Lysate test to determine level of endotoxins.

Particle count and size: Particle numbers and size are determined by NTA using a NS300 instrument (Malvern Panalytical) equipped with a blue laser (488nm). Phage size is -70-1 OOnm.

Identity: SDS-PAGE, Dot and Western blotting with specific antibodies to detect antigen presence on phage particles.

Determination of numbers of displayed proteins per phage: An important aspect of characterization of the TIMRE-BNP will be to determine the relative numbers of each protein displayed per phage. To accomplish this, we will develop a novel method employing mass spectrometrybased parallel reaction monitoring (PRM) applying the recent methodology of Lavado-Garcla, et al.50. Briefly, concentrations of phage as determined by NTA are subjected to trypsin digestion. Target peptides of interest are selected based on the locations of known variant mutations, and corresponding peptides are synthesized to incorporate 13C or 15N for rapid identification and quantitation. Synthesized peptides are added to tryptic digestions and purified by reverse phase HPLC on a C18 column. Resulting peptide mixtures are analyzed by LC/MS-MS. Numbers of resulting peptides for specific antigens can be divided by original particle numbers determined by NTA to calculate the number of antigens per phage. A control peptide from gpD and/or gpE will be used to obtain the total number of gpD/gpE and modified gpD/gpE proteins per phage.

[0066] Subsequent to construction, purification, and characterization of TIMRE- BNPs, they may be formulated for human administration using standard protocols well known to those skilled in the art. Generally, bacteriophage are highly soluble in saline solutions. Routes of administration may include, but are not limited to, intravenous, intramuscular, intraperitoneal and/or intradermal.

[0067] A therapeutic composition including the TIMRE-BNP can be formed according to protocols as are known to those skilled in the art. For instance, purified engineered bacteriophage can be transferred into a buffered saline solution with commonly used preservatives and filter sterilized. Because of the high stability of bacteriophage, a therapeutic composition incorporating an engineered bacteriophage can be stable at ambient and room temperatures for long periods, e.g., one week to several months.

[0068] A therapeutic composition can be prepared in one embodiment as an injectable, either as a liquid solution or suspension. A solid form suitable for solution in, or suspension in, liquid prior to injection may also be prepared. The preparation may also be emulsified, or the ingredients can be mixed with excipients that are pharmaceutically acceptable and compatible with the bacteriophage. Suitable excipients are, for example, saline or buffered saline (pH 7 to 8), or other physiologic, isotonic solutions that may also contain dextrose, glycerol or the like and combinations thereof. In addition, a therapeutic composition can contain minor amounts of auxiliary substances such as wetting or emulsifying agents, pH buffering agents that can enhance the effectiveness of the vaccine. [0069] A therapeutic composition can be prepared in one embodiment as an inhalable composition. For instance, an inhalable therapeutic composition can include the engineered bacteriophage as individual particles or as a component of a larger particle or droplet in which the particle/droplet size facilitates penetration throughout the lungs. In one embodiment, a therapeutic composition designed to be inhaled from a dry powder inhaler can include dry particles comprising engineered bacteriophage as described. In one embodiment, an inhalable composition can include particles or droplets comprising engineered bacteriophage suspended in a propellant, e.g., in the form of an aerosol. In one embodiment, an inhalable composition can be a suspension of droplets or particles comprising engineered bacteriophage held in a liquid carrier that can be intended for administration by use of a liquid nebulizer system. In such an embodiment, a therapeutic composition can incorporate an aqueous liquid carrier, a nonaqueous liquid carrier, or can include a combination of an aqueous and nonaqueous carrier. [0070] A pharmaceutical composition can include individual particles or droplets having a size that can permit penetration into the alveoli of the lungs, generally about 10 pm or less in size, about 7.5 pm or less in size, or about 5 pm or less in size in some embodiments. For instance, when considering aerodynamically light particles (e.g., having a bulk density of about 0.5 g/cm3 or less) for delivery as a dry powder formulation, a pharmaceutical composition can carry larger particles, for instance having a size of from about 5 pm to about 30 pm.

[0071] A therapeutic composition can be delivered by any of the standard routes including but not limited to intramuscular, intravenous, subcutaneous, intradermal, inhalation, etc. A therapeutic composition can be applied or instilled into body cavities, absorbed through the skin (e.g., via a transdermal patch), inhaled, ingested, topically applied to tissue, or administered parenterally via, for instance, intravenous, peritoneal, or intraarterial administration.

[0072] A delivery device can be utilized that allows controlled or sustained release, such as a sponge, biocompatible meshwork, mechanical reservoir, or mechanical implant. Implants and devices as can be useful for administration of a therapeutic composition have been described and are known in the art (see, e.g., U.S. Pat. No. 5,443,505 and U.S. Pat. No. 4,863,457). A therapeutic composition can be administered in the form of sustained-release formulations (see, e.g., U.S. Pat. No. 5,378,475) comprising, for example, gel foam, hyaluronic acid, gelatin, chondroitin sulfate, a polyphosphoester, such as bis-2-hydroxyethyl-terephthalate (BHET), and/or a polylactic-glycolic acid.

[0073] An engineered phage can be used to control and/or treat existing disease and or prophylactically to prevent disease when an individual is concerned about being exposed to a pathogen.

[0074] The dosage of a therapeutic composition administered to a subject can depend on a number of factors, including the extent of any side-effects, the particular route of administration, and the like. The dose ideally comprises an "effective amount" of a therapeutic composition, i.e. , a dose of the binding agent polypeptide carried on an engineered bacteriophage that can prevent activity of the pathogen of interest or otherwise interfere with the disease process.

[0075] The present invention may be better understood with reference to the Examples set forth below.

Prophetic Example 1

[0076] Bispecific TIMRE-BNP for the treatment of prostate cancer

[0077] A TIMRE-BNP can incorporate a first scFv against PSMA and a second scFv against CD3. Use lambda phage as BNP. PSMA is a tumor specific surface antigen on prostate cancer cells. CD3 is a surface antigen on T-cells.

Alternatively or additionally, CD8, which would only recruit cytotoxic T-cells, or CD4 which would only recruit helper T-cells could be targeted.

Prophetic Example 2

[0078] Bispecific TIMRE-BNP w/co-stimulation for the treatment of prostate cancer

[0079] A TIMRE-BNP can incorporate a first scFv against PSMA and a second scFv against CD3 using lambda phage as BNP. PSMA is a tumor specific surface antigen on prostate cancer cells. CD3 is a surface antigen on T-cells. A fragment of B7-1 (CD80), B7-2 (CD86) and/or 41 BBL can also be presented on TIMRE-BNP to induce further T-cell activation.

Prophetic Example 3

[0080] Bispecific TIMRE-BNP with checkpoint inhibition for the treatment of prostate cancer [0081] A TIMRE-BNP can incorporate a first scFv against PSMA and a second scFv against CD3 using lambda phage as BNP. PSMA is a tumor specific surface antigen on prostate cancer cells. CD3 is a surface antigen on T-cells. scFv that block PD-1 on T-cell or PD-L1 on tumor cell can also be presented on the TIMRE- BNP to prevent T-cell de-activation/exhaustion.

Prophetic Example 4

[0082] Bispecific TIMRE-BNP with co-stimulation and checkpoint inhibition for the treatment of prostate cancer

[0083] A TIMRE-BNP can incorporate a first scFv against PSMA and a second scFv against CD3 using lambda phage as BNP. PSMA is a tumor specific surface antigen on prostate cancer cells. CD3 is a surface antigen on T-cells. A fragment of B7-1 (CD80), B7-2 (CD86) and/or 41 BBL can also be presented on TIMRE-BNP to induce further T-cell activation.

Prophetic Example 5

[0084] Bispecific TIMRE-BNP with co-stimulation and checkpoint inhibition and with IL-10 to reduce antigenicity for the treatment of prostate cancer.

[0085] A TIMRE-BNP can incorporate a first scFv against PSMA and a second scFv against CD3 using lambda phage as BNP. PSMA is a tumor specific surface antigen on prostate cancer cells. CD3 is a surface antigen on T-cells. A fragment of B7-1 (CD80), B7-2 (CD86) and/or 41 BBL can also be presented on TIMRE-BNP to induce further T-cell activation. IL-10 can also be presented on the TIMRE- BNP.

Prophetic Example 6

[0086] Bispecific TIMRE-BNP for the treatment of multiple myeloma

[0087] A TIMRE-BNP can incorporate a first scFv against BCMA and a second scFv against CD3 using lambda phage as BNP. B cell maturation antigen (BCMA) can be expressed at significantly higher levels in all patient MM cells but not on other normal tissues except normal plasma cells. CD3 is a surface antigen on T- cells.

Prophetic Example 7

[0088] Bispecific TIMRE-BNP for the treatment of prostate cancer by recruitment of B-cells and helper T-cells [0089] A TIMRE-BNP can incorporate a first scFv against PSMA, a second scFv against CD19, and a third scFv against CD4 using lambda phage as BNP. PSMA is a tumor specific surface antigen on prostate cancer cells. CD19 is a surface antigen on B-cells. CD4 is a surface antigen on helper T-cells.

Prophetic Example 8

[0090] Bispecific TIMRE-BNP for the treatment of prostate cancer by recruiting NK cells.

[0091] A TIMRE-BNP can incorporate a first scFv against BCMA and a second scFv against CD16 using lambda phage as BNP. PSMA is a tumor specific surface antigen on prostate cancer cells. CD16 is a surface antigen on NK cells.

Prophetic Example 9

[0092] Bispecific TIMRE-BNP based on M13 phage for the treatment of prostate cancer.

[0093] A TIMRE-BNP can incorporate a first scFv against BCMA and a second scFv against CD3 using M13 phage as BNP. PSMA is a tumor specific surface antigen on prostate cancer cells. CD3 is a surface antigen on T-cells. Alternatively, CD8, which would only recruit cytotoxic T-cells, or CD4 which would only recruit helper T-cells can be targeted.

[0094] While certain embodiments of the disclosed subject matter have been described using specific terms, such description is for illustrative purposes only, and it is to be understood that changes and variations may be made without departing from the spirit or scope of the subject matter.

Claims

WHAT IS CLAIMED IS:

1 . An engineered multivalent bacteriophage comprising: a first fusion coat protein that includes a first exogenous polypeptide fused to a first bacteriophage coat protein, the first exogenous polypeptide comprising a first targeting polypeptide that includes a binding sequence that binds a first cancer cell surface antigen; a second fusion coat protein that includes a second exogenous polypeptide fused to a second bacteriophage coat protein, the second exogenous polypeptide comprising a second targeting polypeptide that includes a binding sequence that binds a first immune cell surface antigen; wherein the engineered multivalent bacteriophage includes multiple copies of the first fusion coat protein and multiple copies of the second fusion coat protein, the engineered multivalent bacteriophage is free of nucleic acids that encode the first and second exogenous polypeptides, and the engineered multivalent bacteriophage includes the bacteriophage genome.

2. The engineered multivalent bacteriophage of claim 1 , wherein the first exogenous polypeptide comprises a first linking agent between the first bacteriophage coat protein and the first targeting polypeptide, and/or wherein the second exogenous polypeptide comprises a second linking agent between the second bacteriophage coat protein and the second targeting polypeptide.

3. The engineered multivalent bacteriophage of claim 1 or claim 2, wherein the bacteriophage is selected from the group consisting of bacteriophage A, bacteriophage M13, bacteriophage T4, bacteriophage T7, and bacteriophage cpX174.

4. The engineered multivalent bacteriophage of any of the preceding claims, further comprising one or more additional targeting polypeptides that include a binding sequence that binds one or more additional cancer cell surface antigens.

5. The engineered multivalent bacteriophage of any of the preceding claims, wherein the first cancer cell surface antigen is associated with a solid tumor or a hematological tumor, for instance where the first cancer cell surface antigen is selected from the group consisting of aspartyl p-hydroxylase, prostate specific membrane antigen, B-cell maturation antigen, melanoma associated antigen, NY- ESO1 , carcinoembroyonic antigen, human epidermal growth factor receptor 2, CD33, nectin-4, CD30, DCD22, CD79b, and TROP2, and/or wherein the first targeting polypeptide comprises FB50, 622, 15c7, chimeric lgG1 or a fragment thereof, human or humanized lgG1 K or a fragment thereof, or humanized lgG4i , or a fragment thereof.

6. The engineered multivalent bacteriophage any of the preceding claims, wherein the first immune cell surface antigen is a T-cell surface antigen, a B-cell surface antigen, or an NK cell surface antigen, for instance wherein the first immune cell surface antigen is selected from the group consisting of CD3, CD4, CD8, non-polymorphic MHC class l-related protein MR1 , CD25, CD19, CD20, NKp46, and CD16; or wherein the first immune cell surface antigen is a T-cell surface antigen, the engineered multivalent bacteriophage further comprising one or more additional targeting polypeptides that include a binding sequence that binds one or more of a B-cell surface antigen and an NK-cell surface antigen.

7. The engineered multivalent bacteriophage of any of the preceding claims, further comprising a third exogenous polypeptide directly or indirectly fused to the first bacteriophage coat protein, the second bacteriophage coat protein, or a third bacteriophage coat protein, the third exogenous polypeptide comprising an immune response enhancement polypeptide .

8. The engineered multivalent bacteriophage of claim 7, the immune response enhancement polypeptide being configured to block an immune response suppressive checkpoint or being configured to stimulate an immune response activating checkpoint, for instance the immune response enhancement polypeptide comprising a binding sequence that binds PD-L1 , PD-L2, B7-1 , B7-2, MHC-I, MHC-II, or galectin-9 of a cancer cell; or that binds PD-1 , CTLA-4, LAG-3, TIM-3, VISTA, or BTLA of an immune effector cell; or any combination thereof; or that binds 4-1 BB, CD28, ICOS, KIRs, GITR, or any combination thereof

9. The engineered multivalent bacteriophage of any of the preceding claims, further comprising one or more additional exogenous polypeptides, the one or more additional exogenous polypeptides including an Interleukin 10 protein or a fragment thereof, or being directly or indirectly bonded to a detectable label.

10. A therapeutic composition comprising the engineered multivalent bacteriophage of any of the preceding claims and a delivery system, for instance wherein the delivery system is configured to be delivered via an intramuscular, intravenous, subcutaneous, intradermal, or inhalation route.

11. A method for forming an engineered multivalent bacteriophage comprising: transfecting a bacterial cell with one or more expression plasmids, the one or more expression plasmids comprising a first hybrid nucleic acid sequence including a sequence that encodes a first bacteriophage coat protein ligated to and in frame with a sequence that encodes a first targeting polypeptide that includes a binding sequence that binds a cancer cell surface antigen, the one or more expression plasmids further comprising a second hybrid nucleic acid sequence including a sequence that encodes a second bacteriophage coat protein ligated to and in frame with a sequence that encodes a second targeting polypeptide that includes a binding sequence that binds an immune cell surface antigen, the one or more expression plasmids comprising regulatory sequences such that first and second fusion coat proteins encoded by the first and second hybrid nucleic acid sequences are transiently expressed by the bacterial cell following the transfection; and infecting the bacterial cell with a bacteriophage; wherein upon the transfection and the infection, the engineered multivalent, multiplexed bacteriophage is produced by the bacterial cell, the engineered multivalent, multiplexed bacteriophage including the first and second fusion coat proteins at a surface thereof.

12. The method of claim 1 1 , wherein the first hybrid nucleic acid sequence is a component of a first expression plasmid and the second hybrid nucleic acid sequence is a component of a second expression plasmid.

13. The method of claim 11 or claim 12, wherein the regulator sequences comprise a first promoter driving expression of the first fusion coat protein and a second promoter driving expression of the second fusion coat protein, and wherein the first promoter and the second promoter are independently selected from an inducible promoter and a native phage promoter.