CN118139882A

CN118139882A - Treatment of skeletal muscle system diseases

Info

Publication number: CN118139882A
Application number: CN202380013776.4A
Authority: CN
Inventors: 刘晓峰; 刘坤锋; 袁葆直; 李沐宇; 柯华珠
Original assignee: Anjisheng Biopharmaceutical Co ltd
Current assignee: Anjisheng Biomedical Technology Guangzhou Co ltd
Priority date: 2022-03-24
Filing date: 2023-03-24
Publication date: 2024-06-04
Also published as: WO2023179791A9; WO2023179791A1; AR128897A1

Abstract

The present invention provides novel therapeutic molecules for musculoskeletal disorders. Such molecules include bone anabolic promoters such as anti-sclerostin constructs (e.g., anti-sclerostin antibodies) and bone resorption inhibitors that bind to sclerostin. The invention also provides amino acid sequences and methods of making these therapeutic molecules, pharmaceutical compositions comprising these therapeutic molecules, and methods of using these molecules or compositions.

Description

Treatment of skeletal muscle system diseases

Cross Reference to Related Applications

The present application claims priority from international application PCT/CN2022/082878 filed on month 3 of 2022, 24, the contents of which are incorporated herein by reference in their entirety for all purposes.

Technical Field

The present disclosure relates to the treatment of musculoskeletal diseases, bispecific constructs such as anti-Sclerostin (anti-Sclerostin) and anti-RANKL bispecific antibodies, and uses thereof.

Submitting sequence list with ASCII text file

The following contents of the submission of an XML file are incorporated herein by reference in their entirety: computer Readable Form (CRF) of the sequence Listing (file name: MTP220153-1.Seqlist. Xml, date of record: 2023, 3, 24 days, size: 50.1 bytes).

Background

The function of SOST gene product Sclerostin (Sclerostin) as a human bone formation inhibitor was found by genetic profiling studies, which showed that loss of function mutations in SOST gene were responsible for high bone mass osteosclerosis (HBM). In mice, loss of SOST gene results in increased bone mass and bone strength due to increased bone formation, while overexpression of human sclerostin transgene results in decreased bone mass and bone strength.

The disclosures of all publications, patents, patent applications, and published patent applications mentioned herein are incorporated by reference in their entirety.

Disclosure of Invention

The following summary is illustrative only and is not intended to be in any way limiting. That is, the following summary is provided to introduce the bright spots, benefits and advantages of the new molecules and their use. Thus, the following summary is not intended to identify essential features of the claimed subject matter, nor is it intended to be used to determine the scope of the claimed subject matter.

In one aspect, the application provides a bispecific construct comprising an antibody moiety that specifically recognizes sclerostin (e.g., human sclerostin) and a second moiety that specifically recognizes RANKL, wherein the molar ratio of the first antibody moiety to the second antibody moiety is greater than 1:1. In some embodiments, the molar ratio of the first antibody moiety to the second antibody moiety is from 2:1 to 5:1; preferably 2:1 or 3:1. In some embodiments, the antibody moiety is an antibody or antigen-binding fragment thereof selected from the group consisting of a full-length antibody, a bispecific antibody, a single chain Fv (scFv) fragment, a Fab 'fragment, a F (ab') ₂, a Fv fragment, a disulfide stabilized Fv fragment (dsFv), a dsscFv, (dsFv) ₂, an Fv-Fc fusion, a scFv-Fv fusion, a diabody, a triabody, and a tetrabody. In some embodiments, the construct is a full length antibody comprising an Fc fragment. In some embodiments, the antibody moiety is an scFv fragment. In some embodiments, the second moiety comprises a half-life extending moiety (e.g., an Fc fragment). In some embodiments, the second moiety comprises an agent selected from the group consisting of parathyroid hormone (PTH), selective Estrogen Receptor Modulator (SERM), bisphosphonate, prostaglandin E (PGE) receptor agonist, vascular Endothelial Growth Factor (VEGF), transforming growth factor-beta (tgfβ), growth factor (myostatin), and calcitonin.

In some embodiments, the second moiety comprises a second antibody moiety that specifically recognizes an antigen. In some embodiments, bispecific constructs are provided that include a first antibody moiety that specifically recognizes sclerostin (including, but not limited to, the anti-sclerostin antibody moiety described herein) and a second antibody moiety that specifically recognizes a receptor activation factor (RANKL) of a nuclear factor κβ ligand. The antibody moiety that recognizes RANKL may be any anti-RANKL antibody moiety (including but not limited to those described herein). In some embodiments, the second antibody moiety is a full length antibody, fab ', (Fab') ₂, fv, single chain Fv (scFv) fragment, scFv-scFv, minibody, diabody, or sdAb. In some embodiments, the second antibody moiety is a full length antibody comprising an Fc fragment, and wherein the anti-sclerostin antibody moiety is a single chain Fv (scFv) fragment. In some embodiments, the second antibody moiety is a scFv fragment, and wherein the anti-sclerostin antibody moiety is a full length antibody comprising an Fc fragment. In some embodiments, the scFv fragment is fused (with or without a linker) to the heavy and/or light chain (e.g., N-terminal and/or C-terminal) of the full-length antibody. In some embodiments, the construct comprises: a) A first polypeptide comprising a first light chain comprising, from N-terminus to C-terminus, i) V _L, ii) a first light chain constant domain ("first CL domain"); b) A second polypeptide comprising a first heavy chain comprising, from N-terminus to C-terminus, i) V _H, ii) a first heavy chain constant domain ("first CH1 domain"), and iii) a first Fc domain; or i) a heavy chain variable region (V _H), ii) a heavy chain constant domain, iii) a second Fc domain; and iv) an scFv fragment comprising V _H and V _L; c) A third polypeptide comprising a second heavy chain comprising, from N-terminus to C-terminus, i) V _H-2, ii) a second heavy chain constant domain ("second CH1 domain"), and iii) a second Fc domain; and d) a fourth polypeptide comprising a second light chain comprising, from N-terminus to C-terminus, i) V _L-2, ii) a second light chain constant domain ("second CL domain"), wherein the first and second Fc domains form an Fc fragment. The first or second CH1 and/or the first or second Fc domain may have various modifications described herein. In some embodiments, the construct comprises: a) First and second polypeptides comprising a common light chain comprising, from N-terminus to C-terminus, i) a light chain variable region (V _L), ii) a light chain constant domain; b) A third polypeptide comprising a first heavy chain comprising, from N-terminus to C-terminus, i) a heavy chain variable region (V _H), ii) a heavy chain constant domain, iii) a first Fc domain, iv) a heavy chain variable region (V _H), and V) a heavy chain constant domain; or i) a heavy chain variable region (V _H), ii) a heavy chain constant domain, iii) a heavy chain variable region (V _H), iv) a heavy chain constant domain, V) a first Fc domain; c) A fourth polypeptide comprising a second heavy chain comprising, from N-terminus to C-terminus, i) a V _H-2, ii) a heavy chain constant domain, and iii) a second Fc domain; or i) V _H-2, ii) a heavy chain constant domain, and iii) a second Fc domain, iv) a heavy chain variable region (V _H), and V) a heavy chain constant domain; d) A fifth polypeptide comprising a second light chain comprising, from the N-terminus to the C-terminus, i) V _L-2, ii) a light chain constant domain; wherein the first and second Fc domains form an Fc fragment. The first or second CH1 and/or the first or second Fc domain may have various modifications described herein.

Another aspect of the application provides bispecific constructs that competitively specifically bind to sclerostin with any of the bispecific constructs described herein.

In another aspect, the application provides a pharmaceutical composition comprising any of the bispecific constructs described herein and a pharmaceutically acceptable carrier (carrier). In some embodiments, the composition further comprises an agent selected from the group consisting of parathyroid hormone (PTH), selective Estrogen Receptor Modulator (SERM), VEGF, tgfβ, growth factor (myostatin), and calcitonin.

In another aspect, the application provides an isolated nucleic acid encoding any of the bispecific constructs described herein or portions thereof (e.g., one or more polypeptides thereof).

Another aspect of the application provides vectors comprising any of the isolated nucleic acids described herein.

Another aspect of the application provides an isolated host cell comprising any of the isolated nucleic acids and/or any vector described herein.

The application provides in another aspect a method of producing a bispecific construct comprising: a) Culturing any of the isolated host cells described herein under conditions effective to express the bispecific construct or a portion thereof (e.g., one or more polypeptides thereof); and b) obtaining the expressed bispecific construct or part thereof from the host cell.

In another aspect, the application provides a method of treating a disease or condition in an individual comprising administering to the individual an effective amount of a bispecific construct, such as any of the bispecific constructs described herein, or any of the pharmaceutical compositions described herein. In some embodiments, the disease or condition is a bone-related disorder. In some embodiments, the bone-related disorder is osteogenesis imperfecta, osteosclerosis, osteoporosis (in men and/or women), senile osteoporosis, delayed bone healing, delayed or non-healing fractures, paget's disease, inactivity-induced bone loss, glucocorticoid-induced bone loss, inflammation-induced bone loss, including arthritis-induced bone loss or other diseases or conditions associated with a) quantity or quality or both of bone loss and/or b) abnormalities in bone structure and mass. In some embodiments, the bispecific construct or pharmaceutical composition is administered to the subject parenterally. In some embodiments, the method further comprises administering a second agent or therapy (e.g., an anti-RANKL antibody). In some embodiments, the second agent or therapy comprises an agent selected from the group consisting of parathyroid hormone (PTH), selective Estrogen Receptor Modulator (SERM), bisphosphonates, prostaglandin E (PGE) receptor agonists, VEGF, and tgfβ, growth factors (myostatin), and calcitonin. In some embodiments, the individual is a human.

Drawings

FIG. 1 shows the sequence and conformational 'IGRGKWWR' motif on the second loop of sclerostin to illustrate the interaction between sclerostin and LDL receptor associated protein 6 (LRP 6).

FIG. 2 shows a schematic representation of an exemplary bispecific antibody structure.

Detailed Description

The present application provides novel bispecific constructs that specifically bind to sclerostin and other antigens, such as anti-sclerostin and anti-RANKL antibodies or multispecific antibodies, methods of making the bispecific constructs, methods of using the constructs (e.g., methods of treating a disease or condition). The exemplary bispecific constructs described herein achieve advantageous effects.

I. Definition of the definition

The term "antibody" is used in its broadest sense and encompasses a variety of antibody structures, including but not limited to monoclonal antibodies, polyclonal antibodies, multispecific antibodies (e.g., bispecific antibodies), full-length antibodies, and antigen-binding fragments thereof, so long as they exhibit the desired antigen-binding activity. The term "antibody moiety" refers to a full-length antibody or antigen-binding fragment thereof.

Full length antibodies include two heavy chains and two light chains. The variable regions of the light and heavy chains are responsible for antigen binding. The variable domains of the heavy and light chains may be referred to as "V _H" and "V _L", respectively. The variable region in both chains typically comprises three highly variable loops, known as Complementarity Determining Regions (CDRs) (light chain (LC) CDRs including LC-CDR1, LC-CDR2 and LC-CDR3, heavy Chain (HC) CDRs including HC-CDR1, HC-CDR2 and HC-CDR 3). CDR boundaries of the antibodies and antigen binding fragments disclosed herein may be defined or identified by the convention Kabat, chothia or Al-Lazikani. The three CDRs of the heavy or light chain are inserted between flanking regions called Framework Regions (FR), which are more highly conserved than the CDRs and form a scaffold to support the hypervariable loops. The constant regions of the heavy and light chains do not participate in antigen binding, but exhibit various effector functions. Antibodies are classified based on the amino acid sequence of the heavy chain constant region of the antibody. The five main classes or isotypes of antibodies are IgA, igD, igE, igG and IgM, which are characterized by the presence of the alpha, delta, epsilon, gamma and mu heavy chains, respectively. Several major antibody classes are classified into subclasses, such as IgG1 (gamma 1 heavy chain), igG2 (gamma 2 heavy chain), igG3 (gamma 3 heavy chain), igG4 (gamma 4 heavy chain), igA1 (alpha 1 heavy chain), or IgA2 (alpha 2 heavy chain).

The term "antigen-binding fragment" as used herein refers to an antibody fragment, including, for example, diabodies, fab ', F (ab ') ₂, fv fragments, disulfide-stabilized Fv fragments (dsFv), (dsFv) ₂, bispecific dsFv (dsFv-dsFv '), disulfide-stabilized diabodies (dsdiabodies), single chain Fv (scFv), dsscFv, scFv dimers (diabodies), multispecific antibodies formed from a portion of an antibody comprising one or more CDRs, camelized single domain antibodies, nanobodies, domain antibodies, bivalent domain antibodies, or any other antibody fragment that binds an antigen but does not comprise the complete antibody structure. The antigen binding fragment is capable of binding to the same antigen to which the parent antibody or parent antibody fragment (e.g., parent scFv) binds. In some embodiments, an antigen binding fragment may include one or more CDRs from a particular human antibody grafted to a framework region from one or more different human antibodies.

"Fv" is the smallest antibody fragment that includes the complete antigen recognition and binding site. The fragment consists of a dimer of one heavy chain and one light chain variable region domain in close, non-covalent association. Folding of these two domains produces 6 hypervariable loops (3 loops for each of the heavy and light chains) that provide amino acid residues for antigen binding and confer specificity to antibody antigen binding. However, even a single variable domain (or half of an Fv comprising only three antigen-specific CDRs) has the ability to recognize and bind antigen, although with less affinity than the entire binding site.

"Single chain Fv" also abbreviated "sFv" or "scFv" is an antibody fragment comprising V _H and V _L antibody domains linked in a single polypeptide chain. In some embodiments, the scFv polypeptide further comprises a polypeptide linker between the V _H and V _L domains that allows the scFv to form the structure required for antigen binding.

The term "CDR" or "complementarity determining region" as used herein refers to a discontinuous antigen binding site found within the variable regions of heavy and light chain polypeptides. However, the application of either definition to CDRs referring to an antibody or a grafted antibody or variant thereof is intended to be within the scope of the terms as defined and used herein. Amino acid residues comprising CDRs defined by each of the above references are listed as comparisons in table 1 below. The content of the references cited in this paragraph are incorporated herein by reference in their entirety for the purposes of the present application and may be included in one or more of the claims herein. In some embodiments, CDR sequences provided herein are based on IMGT definitions. For example, CDR sequences can be determined by the VBASE2 tool (http:// www.vbase2.org/VBASE2. Php.).

The term "osteoporosis" as used herein refers to pre-menopausal idiopathic osteoporosis, post-menopausal osteoporosis, post-ovariectomy osteoporosis, disuse osteoporosis, drug induced osteoporosis, malabsorption-induced osteoporosis, post-operative malabsorption osteoporosis, and/or senile osteoporosis.

The term "reduced bone mass" as used herein refers to a reduction in premenopausal idiopathic bone mass, post-menopausal bone mass, senile bone mass, drug-induced bone mass, disuse bone mass, neonatal bone mass, and/or space bone mass due to gravity reduction.

The term "metabolic bone disease" as used herein includes, but is not limited to, renal osteodystrophy, primary and secondary hyperparathyroidism, familial hyperparathyroidism syndrome, parathyroid disease, osteodystrophy, osteochondrosis, hyperphosphatemia.

The term "osteonecrosis" as used herein refers to ischemic necrosis of bone, ischemic necrosis secondary to diving, osteonecrosis of jaw.

The term "bone loss" as used herein refers to postmenopausal bone loss, inactivity-related bone loss, weight loss-related bone loss, disease-related facial bone loss, disease-related skull bone loss, disease-related jaw bone loss, disease-related skull bone loss, space travel-related bone loss, glucocorticoid-related bone loss, drug-related bone loss, organ-graft-related bone loss, kidney-graft-related bone loss, HIV-related bone loss, growth hormone loss-related bone loss, cystic fibrosis-related bone loss, chemotherapy-related bone loss, tumor-related bone loss, cancer-related bone loss, hormone ablative bone loss, oral bone loss, heparin-related bone loss, inflammation-related bone loss, bone loss including arthritis-related bone loss, or other diseases or conditions related to a) abnormal mass or quality, or both, and/or b) abnormal bone structure and quality. The weight loss results in bone loss.

The term "non-union" or "delayed bone healing" as used herein refers to delayed or non-union fractures, hip fractures, pseudoarthritis after fusion or arthrodesis, osteolysis, post-operative osteolysis, non-union after spinal arthrodesis, enhancement/acceleration of spinal fusion, chronic pain after arthroplasty.

The term "osteomalacia" as used herein refers to osteomalacia against vitamin D, calcium deficiency, sarcopenia, cancer sarcopenia, tumor-induced osteomalacia.

The term "fracture" as used herein includes, but is not limited to, compression fractures, brittle fractures, pathological fractures, stress fractures, hip fractures, femoral neck fractures, atypical hip fractures, intertrochanteric fractures, fractures in neoplastic disease.

The term "hypercalcemia" as used herein includes hypercalcemia of malignant tumor, myopathy caused by hypercalcemia, hypercalcemia in chronic kidney disease.

The term "multiple myeloma-related bone disorder" as used herein refers to multiple myeloma bone disease and osteoporosis in multiple myeloma.

The term "primary osteotumor" as used herein includes osteosarcoma, osteochondrioma, osteoblastoma, osteochondromyxoma, osteoclast tumor, osteoma, osteoblastoma, chondrosarcoma, chondroblastoma, chondromyxoid fibroma, myxoid chondrosarcoma, sarcoma, ewing's sarcoma, kaposi's sarcoma, periosteum sarcoma, vascular fibrosarcoma, giant cell tumor, giant cell sarcoma, giant cell vascular fibroma, vascular endothelial sarcoma, undifferentiated sarcoma, fibrosarcoma, bone cyst, aneurysm bone cyst, multiple endocrine tumors.

The term "malignant tumor" of "bone metastasis of malignant tumor" includes breast cancer, lung cancer, liver cancer, ovarian cancer, pancreatic cancer, colorectal cancer, gastric cancer, prostate cancer, thyroid cancer, thymus cancer.

The term "inflammatory or infectious bone disease" as used herein refers to osteomyelitis, suppurative osteomyelitis, ankylosing spondylitis.

The term "bone marrow or hematological disorder" as used herein refers to leukemia, malignant lymphoma, hematological malignancy, hematological disorder, bone marrow disease.

The term "musculoskeletal rare disease" as used herein includes osteogenesis imperfecta, stone-like disease (Albers-Schonberg disease), congenital tibial prosthetic joint disease, endophytic osteomatosis, fibrodysplasia, gaucher's disease, marfan's syndrome, multiple hereditary exotoses, neurofibromatosis, osteogenesis imperfecta, osteosclerosis, bone spotting, sclerosing lesions, pseudoarthropathy, lacrimal disease, juvenile arthritis, thalassemia, mucopolysaccharidosis, tenna's syndrome, payne's syndrome, klarfert's syndrome, leprosy, paget's disease, adolescent idiopathic scoliosis, winterchester's syndrome, mandshurdle's disease, ischemic bone diseases (e.g., leg-neck-skin disease, regional migratory osteoporosis), idiopathic infant hypercalcemia, acromegaly hypogonadism, albright-McCune-Sternberg syndrome, aluminum bone disease, ka-Endi's disease (Camurati-ENGELMANN DISEASE), osteoporosis and infant neurite dystrophy, abnormal osteosclerosis, compact osteogenesis imperfecta, gorham-stout syndrome, cystic hemangiomatosis, paget's disease, juvenile Paget's disease, osteoporosis-eyelid hypopigmentation syndrome, osteoporosis in classical or atypical fibrosis, arcuate tibia-radial abnormality-reduced bone mass-fracture, X-linked hypophosphatemia osteomalacia, familial swelling osteolysis, bone spotting, wax tear-like bone disease, skull metaphysis, osteoporosis-pseudoglioma syndrome, skull collarbone dysplasia, hajdu-Cheney syndrome, wincher-Torg syndrome, bone loss in classical or atypical cystic fibrosis, cole-Carpenter syndrome, hypophosphatasia, hereditary hyperphosphatemia, progressive ossified fibrodysplasia, familial hypocalcuria hypercalcemia, pseudo-hypoparathyroidism, acrohypoplasia, eiken syndrome, multiple endogenous osteomatosis, vitamin D hydroxyl deficiency rickets, hypophosphatemic rickets.

The term "cartilage related disorders" as used herein includes, but is not limited to, chondrimatosis, cartilage dysplasia, cartilage dystrophy myotonia, near cortical chondrioma, knee cartilage tearing, osteoarthritis, osteochondral dystrophy.

The term "muscle-related disorder" as used herein includes sarcopenia and cancer sarcopenia.

The term "surgery" as used in "promoting healing after bone or joint surgery" refers to orthopedic surgery, dental surgery, implant surgery, joint replacement, joint maintenance surgery, distraction osteogenesis, bone extension, bone grafting, bone cosmetic surgery, and bone repair such as fracture healing, healing of non-healing, healing of delayed healing, and facial reconstruction.

Table 1: CDR definition

The expression "variable domain residue number in Kabat" or "amino acid position number in Kabat" and variants thereof refers to the numbering system for the heavy chain variable domain or the light chain variable domain of antibody editing in the Kabat numbering scheme system. Using this numbering system, the actual linear amino acid sequence may include fewer or additional amino acids corresponding to shortening or insertion of the FR or hypervariable region (HVR) of the variable domain. For example, the heavy chain variable domain may include a single amino acid insertion following residue 52 of H2 (residue 52A according to Kabat) and an insertion residue following heavy chain FR residue 82 (e.g., residues 82A, 82B, 82C according to Kabat, etc.). For a given antibody, the Kabat numbering of residues may be determined by aligning the homologous regions of the antibody sequence with a "standard" Kabat numbering sequence.

Unless otherwise indicated herein, numbering of residues in the heavy chain of an immunoglobulin is that of the EU index as in the Kabat numbering scheme. The "EU index in Kabat" refers to the residue numbering of the human IgG1 EU antibody.

"Framework" or "FR" residues are those variable domain residues that differ from the CDR residues defined herein.

A "humanized" form of a non-human (e.g., rodent) antibody is a chimeric antibody that includes minimal sequences derived from the non-human antibody. To a large extent, humanized antibodies are human immunoglobulins (recipient antibody) in which residues from a hypervariable region (HVR) of the recipient are replaced by residues from a hypervariable region of a non-human species (donor antibody) such as mouse, rat, rabbit or non-human primate having the desired antibody specificity, affinity and capacity. In some cases, framework Region (FR) residues of the human immunoglobulin are replaced with corresponding non-human residues. In addition, humanized antibodies may include residues not found in the recipient antibody or the donor antibody. These modifications were made to further improve antibody performance. In general, a humanized antibody will comprise substantially all of at least one, and typically two, variable domains, in which all or substantially all of the hypervariable loops correspond to those of a non-human immunoglobulin and all or substantially all of the FR is that of a human immunoglobulin sequence. Humanized antibodies also optionally include at least a portion of an immunoglobulin constant region (Fc), typically that of a human immunoglobulin.

A "human antibody" is an antibody having an amino acid sequence corresponding to a human-produced antibody and/or an antibody prepared using any of the techniques disclosed herein for preparing a human antibody. The definition of human antibodies specifically excludes humanized antibodies that include non-human antigen binding residues. Human antibodies can be prepared by administering an antigen to a transgenic animal that has been modified to produce such antibodies in response to antigen challenge, but whose endogenous loci have been disabled, e.g., immunized xenogeneic mice.

"Percent (%) amino acid sequence identity" or "homology" with respect to the polypeptide and antibody sequences identified herein is defined as the percentage of amino acid residues in a candidate sequence that are identical to the amino acid residues in the polypeptide being compared after aligning the sequences with any conservative substitutions as part of the sequence identity. The alignment used to determine the percent amino acid sequence identity may be accomplished by a variety of methods known to those skilled in the art, for example using publicly available computer software such as BLAST, BLAST-2, ALIGN, megalign (DNASTAR), or MUSCLE software. One skilled in the art can determine appropriate parameters for measuring the alignment, including any algorithms needed to achieve maximum alignment over the full length of the sequences being compared. However, for the purposes herein, the sequence comparison computer program mulce was used to generate amino acid sequence identity% values.

"Homologous" refers to sequence similarity or sequence identity between two polypeptides or between two nucleic acid molecules. When a position in two compared sequences is occupied by the same base or amino acid monomer subunit, for example, if a position in each of two DNA molecules is occupied by adenine, then the molecules are homologous at that position. The percent homology between two sequences is a function of the number of matching or homologous positions shared by the two sequences divided by the number of comparison positions multiplied by 100. For example, if 6 of the 10 positions in two sequences are matched or homologous, then the two sequences are 60% homologous. For example, the DNA sequences ATTGCC and TATGGC have a homology of 50%. Typically, a comparison is made when two sequences are aligned to give maximum homology.

The term "constant domain" refers to the portion of an immunoglobulin molecule having a more conserved amino acid sequence relative to other portions of the immunoglobulin, i.e., variable domains including antigen binding sites. Constant domains include the C _H1、C_H and C _H 3 domains of the heavy chain (collectively C _H) and the CL (or C _L) domain of the light chain.

The "light chains" of antibodies (immunoglobulins) from any mammalian species can be assigned to one of two distinct types, termed kappa ("kappa") and lambda ("lambda"), based on the amino acid sequences of their constant domains. The CL domains of the light chain may be referred to as CK (or C _κ) and CL (or C _λ), respectively.

The "C _H 1 domain" (also referred to as "C1" of the "H1" domain) generally extends from about amino acid 118 to about amino acid 215 (EU numbering system).

The "hinge region" is generally defined as the region of IgG corresponding to Glu216 through Pro230 of human IgG 1. The hinge region of other IgG isotypes can be aligned with the IgG1 sequence by placing the first and last cysteine residues that form the S-S bond between the heavy chains in the same position.

The "C _H 2 domain" (also referred to as the "C2" domain) of the human IgG Fc region typically extends from about amino acid 231 to about amino acid 340. The C _H 2 domain is unique in that it is not tightly paired with another domain. In contrast, two N-linked branched sugar chains were inserted between the two C _H 2 domains of the intact native IgG molecule. It is speculated that the sugar may provide a substituent for the domain-domain pairing and help stabilize the CH2 domain.

The "C _H 3 domain" (also referred to as the "C3" domain) includes the C-terminal residue piece of the C _H 2 domain in the Fc region (i.e., from about amino acid residue 341 to the C-terminal end of the antibody sequence, typically at amino acid residues 446 or 447 of IgG).

The term "Fc region" or "fragment crystallizable region" is used herein to define the C-terminal region of an immunoglobulin heavy chain, including native sequence Fc regions and variant Fc regions. Although the boundaries of the immunoglobulin heavy chain Fc region may vary, the human IgG heavy chain Fc region is generally defined as extending from the amino acid residue at Cys226 or Pro230 to its carboxy terminus. The C-terminal lysine of the Fc region (residue 447 according to the EU numbering system) may be removed, for example, during production or purification of the antibody, or by recombinant engineering of the nucleic acid encoding the heavy chain of the antibody. Thus, a composition of intact antibodies may include a population of antibodies that have all K447 residues removed, a population of antibodies that have no K447 residues removed, and a population of antibodies that have a mixture of antibodies with and without K447 residues. Native sequence Fc regions suitable for use in the antibodies described herein include human IgG1, igG2 (IgG 2A, igG B), igG3, and IgG4.

"Fc receptor" or "FcR" describes a receptor that binds to the Fc region of an antibody. The preferred FcR is a native sequence human FcR. Furthermore, preferred fcrs are those which bind IgG antibodies (gamma receptors) and include fcyri, fcyrii and fcyriii subclasses, including allelic variants and alternatively spliced forms of these receptors, fcyrii receptors including fcyriia ("activated receptors") and fcyriib ("inhibited receptors") which have similar amino acid sequences differing primarily in their cytoplasmic domains. The activation receptor fcyriia includes an immune receptor tyrosine-based activation motif (ITAM) in its cytoplasmic domain. The inhibitory receptor fcyriib includes an immunoreceptor tyrosine-based inhibitory motif (ITIM) in its cytoplasmic domain. The term "FcR" herein includes other fcrs, including those to be identified in the future.

The term "epitope" as used herein refers to a particular group of atoms or amino acids on an antigen to which an antibody or antibody portion binds. Two antibodies or antibody portions may bind to the same epitope within an antigen if they exhibit competitive binding to the antigen.

As used herein, a first antibody or fragment thereof "competes" with a second antibody or fragment thereof for binding to a target antigen when the first antibody or fragment thereof inhibits the second antibody or fragment thereof from binding to the target antigen by at least about 50% (e.g., at least about any of 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 98%, or 99%) in the presence of an equimolar concentration of the first antibody or fragment thereof, or vice versa. High throughput methods based on their cross-competing "pooled" antibodies are described in PCT publication WO 03/48731.

As used herein, the terms "specific binding," "specific recognition," and "specific for" refer to a measurable and reproducible interaction, such as binding between a target and an antibody or antibody moiety, that determines the presence of the target in the presence of a heterogeneous population of molecules (including biomolecules). For example, an antibody or antibody portion that specifically recognizes a target (which may be an epitope) is one that binds the target with greater affinity, avidity, ease, and/or longer duration than it binds to other targets. In some embodiments, the extent of binding of the antibody to an unrelated target is less than about 10% of the binding of the antibody to the target as measured, for example, by a Radioimmunoassay (RIA). In some embodiments, an antibody that specifically binds to a target has a dissociation constant (K _D) of 10 ^-5M、≤10^-6M、≤10^-7M、≤10^-8M、≤10^-9M、≤10^-10M、≤10^-11 M or 10 ^-12 M. In some embodiments, the antibody specifically binds to an epitope on a protein that is conserved among proteins from different species. In some embodiments, specific binding may include, but is not required to, exclusive binding. The binding specificity of an antibody or antigen binding domain can be determined experimentally by methods known in the art. These methods include, but are not limited to, western blots, ELISA, RIA, ECL, IRMA, EIA, BLI, BIACORE ^TM assays, and peptide scans.

An "isolated" antibody (or construct) is an antibody that has been identified, isolated, and/or recovered from a component (e.g., natural or recombinant) of its production environment. Preferably, the isolated polypeptide does not bind to all other components from its production environment.

An "isolated" nucleic acid molecule encoding a construct, antibody or antigen binding fragment thereof as described herein is a nucleic acid molecule identified and isolated from at least one contaminant nucleic acid molecule to which it is normally bound in the environment in which it is produced. Preferably, the isolated nucleic acid does not bind to all components associated with the production environment. The form of the isolated nucleic acid molecules encoding the polypeptides and antibodies described herein differs from the form or environment found in nature. Thus, an isolated nucleic acid molecule differs from nucleic acids encoding polypeptides and antibodies described herein that naturally occur in a cell. An isolated nucleic acid includes a nucleic acid molecule contained in a cell, which typically includes a nucleic acid molecule, but which exists extrachromosomally or at a chromosomal location different from its natural chromosomal location.

A nucleic acid is "operably linked" when it is in a functional relationship with another nucleic acid sequence. For example, if the DNA of the pre-sequence or secretion leader is expressed as a pre-protein involved in the secretion of the polypeptide, it is operably linked to the DNA of the polypeptide; a promoter or enhancer is operably linked to a coding sequence if it affects the transcription of the sequence; or operably linked to a coding sequence if the ribosome binding site is positioned so as to facilitate translation. Typically, "operably linked" means that the DNA sequences being linked are contiguous and, in the case of a secretory leader, contiguous and in reading frame. However, the enhancers do not have to be contiguous. Ligation is accomplished by ligation at convenient restriction sites. If such sites are not present, synthetic oligonucleotide adaptors or linkers are used in accordance with conventional practice.

The term "vector" as used herein refers to a nucleic acid molecule capable of propagating another nucleic acid to which it is linked. The term includes vectors (vectors) which are self-replicating nucleic acid structures as well as vectors (vectors) which integrate into the genome of a host cell into which they have been introduced. Certain vectors are capable of directing the expression of nucleic acids to which they are operably linked. Such vectors are referred to herein as "expression vectors".

The term "transfected" or "transformed" or "transduced" as used herein refers to the process of transferring or introducing an exogenous nucleic acid into a host cell. A "transfected" or "transformed" or "transduced" cell is a cell that has been transfected, transformed or transduced with an exogenous nucleic acid. Cells include primary test cells and their progeny.

The terms "host cell", "host cell line", and "host cell culture" are used interchangeably and refer to cells into which exogenous nucleic acid has been introduced, including the progeny of such cells. Host cells include "transformants" and "transformed cells" which include primary transformed cells and progeny derived therefrom regardless of the number of passages. The progeny may not be exactly the same nucleic acid content as the parent cell and may contain mutations. Included herein are mutant progeny selected or selected for the same function or biological activity in the initially transformed cells.

As used herein, "treatment" or "treatment" is a method for achieving a beneficial or desired result, including clinical results. For the purposes of the present application, beneficial or desired clinical results include, but are not limited to, one or more of the following: reducing one or more symptoms caused by the disease, reducing the extent of the disease, stabilizing the disease, preventing or delaying the spread of the disease, preventing or delaying the recurrence of the disease, delaying or slowing the progression of the disease, improving the disease state, providing remission (partial or complete) of the disease, reducing the dosage of one or more other drugs required to treat the disease, delaying the progression of the disease, increasing or improving quality of life, increasing weight gain, and/or prolongation of survival. The methods of the application encompass any one or more of these therapeutic aspects.

The term "inhibit" or "inhibition" refers to a decrease or cessation of any phenotypic feature or the occurrence, degree, or likelihood of the feature. "reduce" or "inhibit" refers to reducing, decreasing, or preventing activity, function, and/or amount as compared to a reference. In certain embodiments, "reducing" or "inhibiting" refers to the ability to cause an overall reduction of 20% or greater. In another embodiment, "reducing" or "inhibiting" refers to the ability to cause an overall reduction of 50% or greater. In another embodiment, "reducing" or "inhibiting" refers to the ability to cause an overall reduction of 75%, 85%, 90%, 95% or greater.

As used herein, "reference" refers to any sample, standard or level used for comparison purposes. The reference may be obtained from healthy and/or non-diseased samples. In some examples, it may be obtained from a sample of untreated samples. In some examples, a sample from an individual that is not ill or treated. In some examples, the reference is obtained from one or more healthy individuals who are not individuals or patients.

As used herein, "delay of progression of a disease" means delay, impediment, slowing, delaying, stabilizing, inhibiting, and/or delaying the progression of a disease. Such delays may have different lengths of time, depending on the history of the disease and/or the individual being treated. As will be apparent to those of skill in the art, a sufficient or significant delay may actually include prophylaxis, as the individual does not develop a disease.

As used herein, "preventing" includes providing prophylaxis with respect to the occurrence or recurrence of a disease in an individual who may be susceptible to the disease but who has not yet been diagnosed with the disease.

As used herein, "inhibiting" a function or activity is reducing the function or activity when compared to the same condition other than the condition or parameter of interest or alternatively when compared to another condition. For example, an antibody that inhibits tumor growth reduces the growth rate of a tumor compared to the growth rate of a tumor in the absence of the antibody.

The terms "subject," "individual," and "patient" are used interchangeably herein to refer to a mammal, including but not limited to, a human, cow, horse, cat, dog, rodent, or primate. In some embodiments, the individual is a human.

An "effective amount" of an agent refers to an amount effective to achieve the desired therapeutic or prophylactic result over the necessary dosage and period of time. The specific dosage may vary depending on one or more of the following: the particular agent selected, the dosing regimen followed, whether it is administered in combination with other compounds, the timing of administration, the tissue to be imaged, and the physical delivery system in which it is carried.

The terms "pharmaceutical formulation" and "pharmaceutical composition" refer to formulations in a form such that the biological activity of the active ingredient is effective, and which do not include additional components having unacceptable toxicity to the individual to whom the formulation is to be administered. Such formulations may be sterile.

"Pharmaceutically acceptable carrier" refers to a nontoxic solid, semisolid or liquid filler, diluent, encapsulating material, formulation aid or carrier (carrier) conventional in the art for use with therapeutic agents, which comprises the "pharmaceutical composition" for administration to an individual. A pharmaceutically acceptable carrier (carrier) is non-toxic to the recipient at the dosage and concentration used and is compatible with the other ingredients of the formulation. Pharmaceutically acceptable carriers (carriers) are suitable for the formulation used. The pharmaceutically acceptable carrier (carrier) or excipient preferably meets the required criteria for toxicological and manufacturing testing and/or is included on inactive ingredient guidelines prepared by the U.S. food and drug administration.

"Sterile" formulations are sterile or substantially free of viable microorganisms and spores thereof.

Administration "in combination" with one or more other therapeutic agents includes simultaneous (concurrent) and sequential or sequential administration in any order.

The term "simultaneously" is used herein to refer to the administration of two or more therapeutic agents, wherein at least a portion of the administration overlaps in time or wherein the administration of one therapeutic agent falls within a short period of time relative to the administration of the other therapeutic agent. For example, two or more therapeutic agents are administered at intervals of no more than about 60 minutes, such as no more than any of about 30, 15, 10, 5, or 1 minutes.

The term "sequentially" is used herein to refer to the administration of two or more therapeutic agents, wherein the administration of one or more agents continues after the administration of one or more other agents is discontinued. For example, administration of two or more therapeutic agents is administered at intervals of greater than about 15 minutes, such as about 20, 30, 40, 50, or 60 minutes, 1 day, 2 days, 3 days, 1 week, 2 weeks, or 1 month or more.

As used herein, "in combination with … …" refers to the administration of one therapeutic modality in addition to another therapy. Thus, "in combination" refers to the administration of one form of treatment before, during, or after the administration of other forms of treatment to an individual.

The term "package insert" is used to refer to instructions that are typically included in commercial packages of therapeutic products, including information about the indication, usage, dosage, administration, combination therapy, contraindications, and/or warnings regarding the use of such therapeutic products.

An "article of manufacture" is any article of manufacture (e.g., package or container) or kit comprising at least one agent, e.g., a drug for treating a disease or condition, or a probe for specifically detecting a biomarker described herein. In certain embodiments, the article of manufacture or kit is promoted, distributed, or marketed as a unit for practicing the methods described herein.

It should be understood that embodiments of the application described herein include "consisting of …" and/or "consisting essentially of …" embodiments.

References herein to "about" a value or parameter include (and describe) variations with respect to the value or parameter itself. For example, a description relating to "about X" includes a description of "X".

The term "about X-Y" as used herein has the same meaning as "about X to about Y".

As used herein and in the appended claims, the singular forms "a," "or" and "the" include plural referents unless the context clearly dictates otherwise.

Bispecific constructs (targeting both sclerostin and RANKL)

The present application provides bispecific constructs comprising an anti-sclerostin antibody moiety that specifically binds to sclerostin (a product of SOST) and an anti-RANKL antibody moiety as described herein.

The present application provides multispecific constructs that target sclerostin and RANKL. In some embodiments, a multispecific construct is provided that includes a first antibody portion that specifically recognizes sclerostin and a second antibody portion that specifically recognizes RANKL. In some embodiments, the sclerostin is human sclerostin. In some embodiments, RANKL is human RANKL.

RANKL (receptor activator of nuclear factor kappa-B ligand), also known as tumor necrosis factor ligand superfamily member 11 (TNFSF 11), is a ligand for osteoprotegerin and is a key factor in osteoclast differentiation and activation. The protein proved to be a dendritic cell survival factor and involved in the regulation of T cell dependent immune responses. T cell activation has been reported to induce expression of this gene and to result in increased osteoclastogenesis and bone loss. The protein showed activation of the anti-apoptotic kinase AKT/PKB by a signaling complex involving SRC kinase and tumor necrosis factor receptor-related factor (TRAF 6), suggesting that the protein may have a role in the regulation of apoptosis. Targeted disruption of the relevant genes in mice resulted in severe osteosclerotic disease and osteoclast deficiency. Defective mice exhibit defects in early differentiation of T and B lymphocytes and fail to form lobular-alveolar mammary structures during pregnancy.

Exemplary anti-RANKL antibody portions

In some embodiments, an anti-RANKL antibody portion (e.g., scFv) for the multispecific bispecific constructs described herein comprises an antibody portion comprising a heavy chain variable region (V _H) and a light chain variable region (V _L), wherein the antibody portion competes for binding epitopes of RANKL with an antibody or antibody fragment comprising a second heavy chain variable region (V _H-2) and a second light chain variable region (V _L-2), wherein V _H-2 comprises a polypeptide comprising the amino acid sequence of SEQ ID NO:7, comprising the amino acid sequence of SEQ ID NO:8, comprising the amino acid sequence of SEQ ID NO:9, and V _L-2 comprises an HC-CDR3 comprising the amino acid sequence of SEQ ID NO:10, comprising the amino acid sequence of SEQ ID NO:11, comprising the amino acid sequence of SEQ ID NO:12, and LC-CDR3 of the amino acid sequence of seq id no.

In some embodiments, the anti-RANKL antibody portion (e.g., scFv or Fab) for the multispecific bispecific construct comprises an antibody portion comprising a heavy chain variable region (V _H) and a light chain variable region (V _L), wherein V _H comprises an amino acid sequence comprising SEQ ID NO:7, comprising the amino acid sequence of SEQ ID NO:8 and an HC-CDR2 comprising the amino acid sequence of SEQ ID NO:9, and V _L comprises an HC-CDR3 comprising the amino acid sequence of SEQ ID NO:10, comprising the amino acid sequence of SEQ ID NO:11 and an LC-CDR2 comprising the amino acid sequence of SEQ ID NO:12, and LC-CDR3 of the amino acid sequence of seq id no. In some embodiments, V _H comprises SEQ ID NO:13, or a variant comprising an amino acid sequence having at least about 80% (e.g., any of at least about 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99%) sequence identity; and V _L comprises SEQ ID NO:14, or a variant comprising an amino acid sequence having at least about 80% (e.g., any of at least about 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99%) sequence identity.

In some embodiments, the anti-RANKL moiety comprises HC-CDR1, HC-CDR2, and HC-CDR3, each comprising a polypeptide having the amino acid sequence of SEQ ID NO:13, the amino acid sequences of CDR1, CDR2 and CDR3 within the V _H chain region of the sequence shown in seq id no; and LC-CDR1, LC-CDR2 and LC-CDR3, comprising a polypeptide having the amino acid sequence of SEQ ID NO:14, CDR1, CDR2, and CDR3 within the V _L chain region of the sequence shown in seq id no.

In some embodiments, a multispecific construct is provided that includes a first antibody portion that specifically recognizes RANKL and a second antibody portion that specifically recognizes sclerostin, wherein the first antibody portion includes an anti-RANKL single domain antibody (sdAb) portion, and wherein the second antibody portion includes a full-length antibody that includes a heavy chain variable region (V _H) and a second light chain variable region (V _L) and an Fc fragment. In some embodiments, the anti-RANKL sdAb is fused to one or both heavy chains of a full-length antibody comprising an Fc fragment. In some embodiments, the anti-RANKL sdAb is fused to one or both light chains of the full-length antibody. In some embodiments, the anti-RANKL sdAb is fused to the N-terminus of one or both heavy or light chains of the full-length antibody. In some embodiments, the anti-RANKL sdAb is fused to the C-terminus of one or both heavy or light chains of the full-length antibody. In some embodiments, the anti-RANKL sdAb is fused to the full-length antibody through a linker (e.g., any of the linkers described herein). In some embodiments, the anti-RANKL sdAb is not fused to the full-length antibody through a linker.

In some embodiments, a multispecific construct is provided comprising a first antibody portion that specifically recognizes RANKL and a second antibody portion that specifically recognizes sclerostin, wherein the first antibody portion comprises an anti-RANKL single domain antibody (sdAb) portion, wherein the second antibody portion comprises a heavy chain variable region (V _H) and a second light chain variable region (V _L), wherein the construct comprises: a) Two chimeric heavy chains each comprising, from N-terminus to C-terminus, i) V _H, ii) a first heavy chain constant domain ("C _H 1 domain"), iii) an anti-RANKL sdAb, and iv) an Fc domain, wherein the two Fc domains form an Fc fragment; b) Two light chains comprising V _L and a light chain constant domain ("C _L domain"). In some embodiments, the anti-RANKL sdAb is fused to the Fc domain through a first linker. In some embodiments, the anti-RANKL sdAb is fused to V _H via a second linker.

In some embodiments, a multispecific construct is provided that includes a first antibody portion that specifically recognizes RANKL and a second antibody portion that specifically recognizes sclerostin, wherein the first antibody portion includes an anti-RANKL single domain antibody (sdAb) portion, wherein the second antibody portion includes a heavy chain variable region (V _H) and a second light chain variable region (V _L), and wherein the construct includes: a) A first heavy chain comprising, from N-terminus to C-terminus, i) an anti-RANKL sdAb, and ii) a first Fc domain; b) A second heavy chain comprising, from the N-terminus to the C-terminus, i) V _H, ii) a first heavy chain constant domain ("C _H domain"), and iii) a second Fc domain; and C) a light chain comprising V _L and a light chain constant domain ("C _L domain"), wherein the first and second Fc domains form an Fc fragment.

In some embodiments, one of the first and second Fc domains comprises a T366W mutation and optionally an S354C mutation, and wherein the other Fc domain comprises a T366S mutation, an L368A mutation, a Y407V mutation, and optionally a Y349C mutation.

In some embodiments, wherein the second antibody portion competes for binding epitope of RANKL with a third antibody portion comprising a second heavy chain variable region (V _H-2) and a second light chain variable region (V _L-2), wherein V _H-2 comprises a polypeptide comprising SEQ ID NO:7, comprising the amino acid sequence of SEQ ID NO:8 and an HC-CDR2 comprising the amino acid sequence of SEQ ID NO:9, and V _L-2 comprises an HC-CDR3 comprising the amino acid sequence of SEQ ID NO:10, comprising the amino acid sequence of SEQ ID NO:11 and an LC-CDR2 comprising the amino acid sequence of SEQ ID NO:12, and LC-CDR3 of the amino acid sequence of seq id no. In some embodiments, V _H comprises a polypeptide comprising SEQ ID NO:7, comprising the amino acid sequence of SEQ ID NO:8 and an HC-CDR2 comprising the amino acid sequence of SEQ ID NO:9, and V _L comprises an HC-CDR3 comprising the amino acid sequence of SEQ ID NO:10, comprising the amino acid sequence of SEQ ID NO:11 and an LC-CDR2 comprising the amino acid sequence of SEQ ID NO:12, and LC-CDR3 of the amino acid sequence of seq id no.

In some embodiments, the bispecific construct is a multispecific (e.g., bispecific) bispecific construct comprising a) an anti-sclerostin antibody moiety according to any one of the anti-sclerostin antibody moieties described herein; b) A second antibody moiety that specifically recognizes RANKL (an anti-RANKL antibody moiety, e.g., any of the anti-RANKL antibody moieties described herein). In some embodiments, anti-sclerostin V _H comprises i) a polypeptide comprising SEQ ID NO:1, ii) an HC-CDR1 comprising the amino acid sequence of SEQ ID NO:2, and iii) an HC-CDR2 comprising the amino acid sequence of SEQ ID NO:3 or a variant thereof comprising up to 5, 4, 3,2 or 1 amino acid substitutions in the HC-CDR, and anti-sclerostin V _L comprises i) a polypeptide comprising SEQ ID NO:4, ii) LC-CDR1 comprising the amino acid sequence of SEQ ID NO:5, and iii) an LC-CDR2 comprising the amino acid sequence of SEQ ID NO:6, or a variant thereof comprising up to 5, 4, 3,2 or 1 amino acid substitutions in the LC-CDR.

In some embodiments, anti-sclerostin V _H comprises i) a polypeptide comprising SEQ ID NO:1, ii) an HC-CDR1 comprising the amino acid sequence of SEQ ID NO:2, and iii) an HC-CDR2 comprising the amino acid sequence of SEQ ID NO:3 or a variant thereof comprising up to 5, 4, 3, 2 or 1 amino acid substitutions in the HC-CDR, and anti-sclerostin V _L comprises i) a polypeptide comprising SEQ ID NO:26, and a LC-CDR1 of the amino acid sequence of seq id no. ii) comprises SEQ ID NO:5, and iii) an LC-CDR2 comprising the amino acid sequence of SEQ ID NO:6, or a variant thereof comprising up to 5, 4, 3, 2 or 1 amino acid substitutions in the LC-CDR.

In some embodiments, the amino acid substitutions described above are limited to the "exemplary substitutions" shown in table 2 of the present application. In some embodiments, amino acid substitutions are limited to the "preferred substitutions" shown in table 2 of the present application.

In some embodiments, the bispecific construct comprises a) an anti-sclerostin full-length antibody comprising two heavy chains and two light chains, wherein the two heavy chains each comprise a heavy chain variable region (V _H) and the two light chains each comprise a light chain variable region (V _L), b) an anti-RANKL antibody portion (e.g., any of the antibody portions described herein) fused to at least one or both heavy chains of the anti-sclerostin full-length antibody. In some embodiments, the anti-RANKL antibody moiety is fused to the N-terminus of one or both heavy chains. In some embodiments, the anti-RANKL antibody moiety is fused to the C-terminus of one or both heavy chains.

In some embodiments, the bispecific construct comprises a) an anti-RANKL antibody portion comprising a full length antibody comprising two heavy chains and two light chains, wherein the two heavy chains each comprise a heavy chain variable region (V _H) and the two light chains each comprise a light chain variable region (V _L), b) an anti-sclerostin antibody portion fused to at least one or both heavy chains of the anti-RANKL full length antibody (e.g., any of the anti-sclerostin antibody portions described herein). In some embodiments, the anti-sclerostin antibody moiety is fused to the N-terminus of one or both heavy chains. In some embodiments, the anti-sclerostin antibody moiety is fused to the C-terminus of one or both heavy chains.

In some embodiments, the bispecific construct comprises a) an anti-sclerostin full-length antibody comprising two heavy chains and two light chains, wherein the two heavy chains each comprise a heavy chain variable region (V _H) and the two light chains each comprise a light chain variable region (V _L), b) an anti-RANKL antibody portion (e.g., any of the antibody portions described herein) fused to at least one or both light chains of the anti-sclerostin full-length antibody. In some embodiments, the anti-RANKL antibody moiety is fused to the N-terminus of one or both light chains. In some embodiments, the anti-RANKL antibody moiety is fused to the C-terminus of one or both light chains.

In some embodiments, the bispecific construct comprises a) an anti-RANKL antibody portion comprising a full length antibody comprising two heavy chains and two light chains, wherein the two heavy chains each comprise a heavy chain variable region (V _H) and the two light chains each comprise a light chain variable region (V _L), b) an anti-sclerostin antibody portion (e.g., any of the antibody portions described herein) fused to at least one or both light chains of the anti-RANKL full length antibody. In some embodiments, the anti-sclerostin antibody moiety is fused to the N-terminus of one or both light chains. In some embodiments, the anti-sclerostin antibody moiety is fused to the C-terminus of one or both light chains.

In some embodiments, a multispecific construct is provided that includes a first antibody portion that specifically recognizes sclerostin and a second antibody portion that specifically recognizes RANKL, wherein the first antibody portion includes a single chain Fv fragment (scFv) comprising a first heavy chain variable region (V _H-1) and a first light chain variable region (V _L-1), and wherein the second antibody portion is a full-length antibody that includes a second heavy chain variable region (V _H-2), a second light chain variable region (V _L-2), and an Fc fragment. In some embodiments, the first antibody moiety is fused to one or both heavy chains of a full length antibody. In some embodiments, the first antibody moiety is fused to one or both light chains of the full length antibody. In some embodiments, the first antibody moiety is fused to the N-terminus of one or both of the heavy chain or the light chain of the full length antibody. In some embodiments, the first antibody moiety is fused to the C-terminus of one or both heavy or light chains of the full length antibody. In some embodiments, the first antibody moiety is fused to the full length antibody by a first linker (e.g., any of the linkers described herein). In some embodiments, the first antibody moiety is not fused to the full length antibody through a linker. In some embodiments, V _H-1 is fused to V _L-1 by a second linker (e.g., any of the linkers described herein).

In some embodiments, a multispecific construct is provided that includes a first antibody portion that specifically recognizes sclerostin and a second antibody portion that specifically recognizes RANKL, wherein the first antibody portion is a full-length antibody that includes a first heavy chain variable region (V _H-1), a first light chain variable region (V _L-1), and an Fc fragment, and wherein the second antibody portion includes a single chain Fv fragment (scFv) that includes a second heavy chain variable region (V _H-2) and a second light chain variable region (V _L-2). In some embodiments, the second antibody moiety is fused to one or both heavy chains of the full length antibody. In some embodiments, the second antibody moiety is fused to one or both light chains of the full length antibody. In some embodiments, the second antibody moiety is fused to the N-terminus of one or both of the heavy chain or the light chain of the full length antibody. In some embodiments, the second antibody moiety is fused to the C-terminus of one or both heavy or light chains of the full length antibody. In some embodiments, the second antibody moiety is fused to the full-length antibody via a first linker (e.g., any of the linkers described herein). In some embodiments, the second antibody moiety is not fused to the full length antibody through a linker. In some embodiments, V _H-2 is fused to V _L-2 by a second linker (e.g., any of the linkers described herein) to achieve proper scFv assembly. In some embodiments, V _H-2 is not fused to V _L-2 by a linker.

In some embodiments, a multispecific construct is provided that includes a first antibody portion that specifically recognizes sclerostin and a second antibody portion that specifically recognizes RANKL, wherein the first antibody portion is a full-length antibody that includes a first heavy chain variable region (V _H-1), a first light chain variable region (V _L-1), and an Fc fragment, and wherein the second antibody portion includes a single chain Fv fragment (scFv) that includes a second heavy chain variable region (V _H-2) and a second light chain variable region (V _L-2). In some embodiments, the second antibody moiety is fused to only one of the heavy chains of the full length antibody. In some embodiments, the second antibody moiety is fused to the full-length antibody via a first linker (e.g., any of the linkers described herein). In some embodiments, the second antibody moiety is not fused to the full length antibody through a linker. In some embodiments, V _H-2 is fused to V _L-2 by a second linker (e.g., any of the linkers described herein) to achieve proper scFv assembly. In some embodiments, V _H-2 is not fused to V _L-2 by a linker.

In some embodiments, a multispecific construct that specifically recognizes sclerostin and RANKL is provided that includes a first antibody portion and a second antibody, wherein the first antibody portion includes a first heavy chain variable region (V _H-1) and a first light chain variable region (V _L-1), and wherein the second antibody portion includes a second heavy chain variable region (V _H-2) and a second light chain variable region (V _L-2), wherein the construct includes: a) A first polypeptide comprising a first light chain comprising, from N-terminus to C-terminus, i) V _L-1, ii) a first light chain constant domain ("first CL domain"); b) A second polypeptide comprising a first heavy chain from N-terminus to C-terminus, i) V _H-1, ii) a first heavy chain constant domain ("first CH1 domain"), and iii) a first Fc domain; or i) a heavy chain variable region (V _H), ii) a heavy chain constant domain, iii) a second Fc domain; and iv) an scFv fragment comprising V _H and V _L; c) A third polypeptide comprising a second heavy chain comprising, from N-terminus to C-terminus, i) V _H-2, ii) a second heavy chain constant domain ("second CH1 domain"), and iii) a second Fc domain; and d) a fourth polypeptide comprising, from N-terminus to C-terminus, a second light chain, i) V _L-2, ii) a second light chain constant domain ("second CL domain"), wherein the first and second Fc domains form an Fc fragment. In some embodiments, the first antibody moiety specifically recognizes sclerostin and the second antibody moiety specifically recognizes RANKL. In some embodiments, the first antibody moiety specifically recognizes RANKL and the second antibody moiety specifically recognizes sclerostin.

In some embodiments, one of the first and second Fc domains comprises a T366W mutation, and optionally an S354C mutation, and wherein the other Fc domain comprises a T366S mutation, an L368A mutation, a Y407V mutation, and optionally a Y349C mutation, wherein numbering is according to the EU index.

In some embodiments, a multispecific construct is provided comprising a first antibody portion that specifically recognizes sclerostin and a second antibody portion that specifically recognizes RANKL, wherein the first antibody portion is an anti-sclerostin antibody comprising two fabs and one Fc fragment, wherein the two fabs each comprise a first heavy chain variable region (V _H-1) and a first light chain variable region (V _L-1), wherein the second Fab fragment is fused to the N-terminus of V _H-1 of the first Fab or to the C-terminus of the Fc region to which the first Fab is linked, and wherein the second antibody portion comprises an anti-RANKL half antibody, it includes a second heavy chain variable region (V _H-2) and a second light chain variable region (V _L-2). In some embodiments, V _H-1 comprises SEQ ID NO:27 or a variant comprising an amino acid sequence having at least about 80% (such as at least about any one of 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99%) sequence identity; and V _L-1 comprises SEQ ID NO:28 or 29, or a variant comprising an amino acid sequence having at least about 80% (e.g., any of at least about 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99%) sequence identity. In some embodiments, V _H-2 comprises a polypeptide comprising SEQ ID NO:7, comprising the amino acid sequence of SEQ ID NO:8 and an HC-CDR2 comprising the amino acid sequence of SEQ ID NO:9, and V _L-2 comprises an HC-CDR3 comprising the amino acid sequence of SEQ ID NO:10, comprising the amino acid sequence of SEQ ID NO:11 and an LC-CDR2 comprising the amino acid sequence of SEQ ID NO:12, and LC-CDR3 of the amino acid sequence of seq id no. In some embodiments, V _H-2 comprises SEQ ID NO:13 or a variant comprising an amino acid sequence having at least about 80% (such as at least about any one of 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99%) sequence identity; and V _L-2 comprises SEQ ID NO:14, or a variant comprising an amino acid sequence having at least about 80% (e.g., any of at least about 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99%) sequence identity.

In some embodiments, multi-specific (e.g., bispecific) anti-sclerostin constructs are provided that include: a) A first antibody portion that specifically recognizes sclerostin, comprising a first heavy chain variable region (V _H-1) and a first light chain variable region (V _L-1), wherein V _H-1 comprises a polypeptide comprising SEQ ID NO:1 comprising the amino acid sequence of SEQ ID NO:2 and an HC-CDR2 comprising the amino acid sequence of SEQ ID NO:3, V _L-1 comprises an HC-CDR3 comprising the amino acid sequence of SEQ ID NO:4, LC-CDR1 of the amino acid sequence of seq id no, comprising SEQ ID NO:5, and an LC-CDR2 comprising the amino acid sequence of SEQ ID NO:6, and b) a second antibody portion that specifically recognizes RANKL, comprising a second heavy chain variable region (V _H-2) and a second light chain variable region (V _L-2), wherein V _H-2 comprises a polypeptide comprising the amino acid sequence of SEQ ID NO:7, comprising the amino acid sequence of SEQ ID NO:8, comprising the amino acid sequence of SEQ ID NO:9, HC-CDR3 of the amino acid sequence of, v _L-2 comprises a polypeptide comprising SEQ ID NO:10, comprising the amino acid sequence of SEQ ID NO:11, comprising the amino acid sequence of SEQ ID NO:12, and LC-CDR3 of the amino acid sequence of seq id no. In some embodiments, V _H-1 comprises SEQ ID NO:27, and V _L-1 comprises the amino acid sequence of SEQ ID NO:28, and a sequence of amino acids. In some embodiments, the first antibody portion is a full length antibody comprising two heavy chains and two light chains, and the second antibody portion is an scFv comprising V _H-2 and V _L-2. In some embodiments, V _H-2 is fused to the N-terminus of V _L-2. In some embodiments, V _H-2 is fused to the C-terminus of V _L-2, optionally with the addition of a single alanine amino acid at the C-terminus of V _H-2. In some embodiments, V _H-2 and V _L-2 are fused by a linker (e.g., a GS linker, such as (GGGGS) ₄). In some embodiments, the second antibody moiety is fused to the N-terminus of one or both heavy chains of the full length antibody. In some embodiments, the second antibody moiety is fused to the C-terminus of one or both heavy chains of the full length antibody. In some embodiments, the second antibody moiety is fused to the N-terminus of one or both light chains of the full length antibody. In some embodiments, the second antibody moiety is fused to the C-terminus of one or both light chains of the full length antibody. In some embodiments, the second antibody portion is a full length antibody comprising two heavy chains and two light chains, and the first antibody portion is a scFv comprising V _H-1 and V _L-1. In some embodiments, V _H-1 is fused to the N-terminus of V _L-1. In some embodiments, V _H-1 is fused to the C-terminus of V _L-1, optionally with the addition of a single alanine amino acid at the C-terminus of V _H-1. In some embodiments, V _H-1 and V _L-1 are fused by a linker (e.g., a GS linker, such as (GGGGS) ₄). In some embodiments, the first antibody moiety is fused to the N-terminus of one or both heavy chains of the full length antibody. In some embodiments, the first antibody moiety is fused to the C-terminus of one or both heavy chains of the full length antibody. In some embodiments, the first antibody moiety is fused to the N-terminus of one or both light chains of the full length antibody. In some embodiments, the first antibody moiety is fused to the C-terminus of one or both light chains of the full length antibody. In some embodiments, the first antibody moiety and the second antibody moiety are fused by a linker (e.g., a GS linker, such as (GGGGS) ₃). In some embodiments, the first antibody moiety and the second antibody moiety are not fused by a linker.

In some embodiments, multi-specific (e.g., bispecific) anti-sclerostin constructs are provided that include: a) A first antibody portion that specifically recognizes sclerostin, comprising a first heavy chain variable region (V _H-1) and a first light chain variable region (V _L-1), wherein V _H-1 comprises a polypeptide comprising SEQ ID NO:1 comprising the amino acid sequence of SEQ ID NO:2 and an HC-CDR2 comprising the amino acid sequence of SEQ ID NO:3, V _L-1 comprises an HC-CDR3 comprising the amino acid sequence of SEQ ID NO:4, LC-CDR1 of the amino acid sequence of seq id no, comprising SEQ ID NO:5, and an LC-CDR2 comprising the amino acid sequence of SEQ ID NO:6, and b) a second antibody portion that specifically recognizes RANKL, comprising a second heavy chain variable region (V _H-2) and a second light chain variable region (V _L-2), wherein V _H-2 comprises a polypeptide comprising the amino acid sequence of SEQ ID NO:7, comprising the amino acid sequence of SEQ ID NO:8, comprising the amino acid sequence of SEQ ID NO:9, HC-CDR3 of the amino acid sequence of, v _L-2 comprises a polypeptide comprising SEQ ID NO:10, comprising the amino acid sequence of SEQ ID NO:11, comprising the amino acid sequence of SEQ ID NO:12, and LC-CDR3 of the amino acid sequence of seq id no. In some embodiments, V _H-1 comprises SEQ ID NO:27, and V _L-1 comprises the amino acid sequence of SEQ ID NO: 29. In some embodiments, the first antibody portion is a full length antibody comprising two heavy chains and two light chains, and the second antibody portion is an scFv comprising V _H-2 and V _L-2. In some embodiments, V _H-2 is fused to the N-terminus of V _L-2. In some embodiments, V _H-2 is fused to the C-terminus of V _L-2, optionally with the addition of a single alanine amino acid at the C-terminus of V _H-2. In some embodiments, V _H-2 and V _L-2 are fused by a linker (e.g., a GS linker, such as (GGGGS) ₄). In some embodiments, the second antibody moiety is fused to the N-terminus of one or both heavy chains of the full length antibody. In some embodiments, the second antibody moiety is fused to the C-terminus of one or both heavy chains of the full length antibody. In some embodiments, the second antibody moiety is fused to the N-terminus of one or both light chains of the full length antibody. In some embodiments, the second antibody moiety is fused to the C-terminus of one or both light chains of the full length antibody. In some embodiments, the second antibody portion is a full length antibody comprising two heavy chains and two light chains, and the first antibody portion is a scFv comprising V _H-1 and V _L-1. In some embodiments, V _H-1 is fused to the N-terminus of V _L-1. In some embodiments, V _H-1 is fused to the C-terminus of V _L-1, optionally with the addition of a single alanine amino acid at the C-terminus of V _H-1. In some embodiments, V _H-1 and V _L-1 are fused by a linker (e.g., a GS linker, such as (GGGGS) ₄). In some embodiments, the first antibody moiety is fused to the N-terminus of one or both heavy chains of the full length antibody. In some embodiments, the first antibody moiety is fused to the C-terminus of one or both heavy chains of the full length antibody. In some embodiments, the first antibody moiety is fused to the N-terminus of one or both light chains of the full length antibody. In some embodiments, the first antibody moiety is fused to the C-terminus of one or both light chains of the full length antibody. In some embodiments, the first antibody moiety and the second antibody moiety are fused by a linker (e.g., a GS linker, such as (GGGGS) ₃). In some embodiments, the first antibody moiety and the second antibody moiety are not fused by a linker.

In some embodiments, a multispecific (e.g., bispecific) construct is provided comprising a first antibody portion that specifically recognizes sclerostin and a second antibody portion that specifically recognizes RANKL, wherein the multispecific construct comprises two heavy chains and two light chains, wherein the two light chains comprise the amino acid sequence of SEQ ID NO:30, the first heavy chain comprises the amino acid sequence of SEQ ID NO:33, and the second heavy chain comprises the amino acid sequence of SEQ ID NO:34, and a sequence of amino acids.

In some embodiments, a multispecific (e.g., bispecific) construct is provided comprising a first antibody portion that specifically recognizes sclerostin and a second antibody portion that specifically recognizes RANKL, wherein the multispecific construct comprises two heavy chains and two light chains, wherein the two light chains comprise the amino acid sequence of SEQ ID NO:30, the first heavy chain comprises the amino acid sequence of SEQ ID NO:36, and the second heavy chain comprises the amino acid sequence of SEQ ID NO:37, and a sequence of amino acids thereof.

In some embodiments, a multispecific (e.g., bispecific) construct is provided comprising a first antibody portion that specifically recognizes sclerostin and a second antibody portion that specifically recognizes RANKL, wherein the multispecific construct comprises two heavy chains and two light chains, wherein the two light chains comprise the amino acid sequence of SEQ ID NO:30, the first heavy chain comprises the amino acid sequence of SEQ ID NO:42, and the second heavy chain comprises the amino acid sequence of SEQ ID NO: 43.

In some embodiments, a multispecific (e.g., bispecific) construct is provided comprising a first antibody portion that specifically recognizes sclerostin and a second antibody portion that specifically recognizes RANKL, wherein the multispecific construct comprises two heavy chains and two light chains, wherein the two light chains comprise the amino acid sequence of SEQ ID NO:30, the first heavy chain comprises the amino acid sequence of SEQ ID NO:46, and the second heavy chain comprises the amino acid sequence of SEQ ID NO: 47.

In some embodiments, the anti-RANKL antibody moiety and the anti-sclerostin antibody moiety are fused to each other via a linker, such as any of the linkers described herein, in any operable form that allows for proper function of the binding moiety.

In some embodiments, a multispecific construct is provided comprising a first antibody portion that specifically recognizes endostatin and a second antibody portion that specifically recognizes RANKL, wherein the first antibody portion is an anti-endostatin full length antibody comprising two heavy chains and two light chains, wherein the two heavy chains each comprise a first heavy chain variable region (V _H-1), wherein the two light chains each comprise a first light chain variable region (V _L-1), and wherein the second antibody portion comprises an anti-RANKL single chain Fv fragment (scFv) comprising a second heavy chain variable region (V _H-2) and a second light chain variable region (V _L-2), wherein the second antibody moiety is fused to the C-terminus of one of the two heavy chains of the full-length anti-sclerostin antibody. In some embodiments, V _H-1 comprises SEQ ID NO:27 or a variant comprising an amino acid sequence having at least about 80% (such as at least about any one of 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99%) sequence identity; and V _L-1 comprises SEQ ID NO:28 or 29, or a variant comprising an amino acid sequence having at least about 80% (e.g., any of at least about 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99%) sequence identity. In some embodiments, V _H-2 comprises a polypeptide comprising SEQ ID NO:7, comprising the amino acid sequence of SEQ ID NO:8 and an HC-CDR2 comprising the amino acid sequence of SEQ ID NO:9, and V _L-2 comprises an HC-CDR3 comprising the amino acid sequence of SEQ ID NO:10, comprising the amino acid sequence of SEQ ID NO:11 and an LC-CDR2 comprising the amino acid sequence of SEQ ID NO:12, and LC-CDR3 of the amino acid sequence of seq id no. In some embodiments, V _H-2 comprises SEQ ID NO:13 or a variant comprising an amino acid sequence having at least about 80% (such as at least about any one of 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99%) sequence identity; and V _L-2 comprises SEQ ID NO:14, or a variant comprising an amino acid sequence having at least about 80% (e.g., any of at least about 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99%) sequence identity.

In some embodiments, a multispecific (e.g., bispecific) construct is provided comprising a first antibody portion that specifically recognizes sclerostin and a second antibody portion that specifically recognizes RANKL, wherein the multispecific construct comprises two heavy chains and three light chains, wherein the first and second light chains comprise the amino acid sequence of SEQ ID NO:31 and the third light chain comprises the amino acid sequence of SEQ id no:32, the first heavy chain comprises the amino acid sequence of SEQ ID NO:38, and the second heavy chain comprises the amino acid sequence of SEQ ID NO:39, and a sequence of amino acids.

In some embodiments, a multispecific (e.g., bispecific) construct is provided comprising a first antibody portion that specifically recognizes sclerostin and a second antibody portion that specifically recognizes RANKL, wherein the multispecific construct comprises two heavy chains and three light chains, wherein the first and second light chains comprise the amino acid sequence of SEQ ID NO:31 and the third light chain comprises the amino acid sequence of SEQ ID NO:32, the first heavy chain comprises the amino acid sequence of SEQ ID NO:38, and the second heavy chain comprises the amino acid sequence of SEQ ID NO: 41.

In some embodiments, a multispecific (e.g., bispecific) construct is provided comprising a first antibody portion that specifically recognizes sclerostin and a second antibody portion that specifically recognizes RANKL, wherein the multispecific construct comprises two heavy chains and three light chains, wherein the first and second light chains comprise the amino acid sequence of SEQ ID NO:31 and the third light chain comprises the amino acid sequence of SEQ ID NO:32, the first heavy chain comprises the amino acid sequence of SEQ ID NO:40, and the second heavy chain comprises the amino acid sequence of SEQ ID NO: 41.

In some embodiments, a multispecific (e.g., bispecific) construct is provided comprising a first antibody portion that specifically recognizes sclerostin and a second antibody portion that specifically recognizes RANKL, wherein the multispecific construct comprises two heavy chains and three light chains, wherein the first and second light chains comprise the amino acid sequence of SEQ ID NO:31 and the third light chain comprises the amino acid sequence of SEQ ID NO:32, the first heavy chain comprises the amino acid sequence of SEQ ID NO:44, and the second heavy chain comprises the amino acid sequence of SEQ ID NO: 45.

In some embodiments, the construct comprises or is an antibody or antigen-binding fragment thereof selected from the group consisting of a full-length antibody, a bispecific antibody, a single chain Fv (scFv) fragment, a Fab 'fragment, a F (ab') ₂, a Fv fragment, a disulfide stabilized Fv fragment (dsFv), a dsscFv, (dsFv) ₂, a VHH, a Fv-Fc fusion, a scFv-Fv fusion, a diabody, a triabody, and a tetrabody.

In some embodiments, the anti-sclerostin antibody and/or the anti-RANKL antibody moiety is a full length antibody.

In some embodiments, the anti-sclerostin antibody and/or anti-RANKL antibody moiety is an scFv or a dsscFv.

In some embodiments, the above-described anti-sclerostin antibody moiety and/or anti-RANKL antibody comprises an Fc fragment of an immunoglobulin selected from the group consisting of IgG, igA, igD, igE, igM and combinations and hybrids thereof. In some embodiments, the anti-sclerostin antibody described above comprises an Fc fragment of an immunoglobulin selected from the group consisting of IgG1, igG2, igG3, igG4, and combinations and hybrids thereof. In some embodiments, the Fc fragment has reduced effector function compared to a corresponding wild-type Fc fragment. In some embodiments, the Fc fragment has enhanced effector function as compared to a corresponding wild-type Fc fragment.

In some embodiments, the antibody moiety comprises a humanized antibody of any of the antibody moieties described herein.

In some embodiments, the bispecific construct comprises a fusion protein or fusion protein.

In some embodiments, the bispecific construct comprises or is a multispecific bispecific construct (e.g., a bispecific antibody).

In some embodiments, the sclerostin is human sclerostin and/or the RANKL is human RANKL.

A) Affinity for antibodies

The binding specificity of the antibody moiety can be determined experimentally by methods known in the art. These methods include, but are not limited to, western blots, ELISA, RIA, ECL, IRMA, EIA, BLI, BIACORE ^TM assays, and peptide scans.

In some embodiments, the K _D for binding between the antibody moiety and sclerostin and/or RANKL is from about 10 ^-7 M to about 10 ^-12 M, from about 10 ^-7 M to about 10 ^-8 M, from about 10 ^-8 M to about 10 ^-9 M, from about 10 ^-9 M to about 10 ^-10 M, from about 10 ^-10 M to about 10 ^-11 M, from about 10 ^-11 M to about 10 ^-12 M, About 10 ^-7 M to about 10 ^-12 M, about 10 ^-8 M to about 10 ^-12 M, about 10 ^-9 M to about 10 ^-12 M, about 10 ^-10 M to about 10 ^- ¹² M, about 10 ^-7 M to about 10 ^-11 M, about 10 ^-8 M to about 10 ^-11 M, about 10 ^-9 M to about 10 ^-11 M, About 10 ^-7 M to about 10 ^-10 M, about 10 ^-8 M to about 10 ^-10 M, or about 10 ^-7 M to about 10 ^-9 M. In some embodiments, the K _D of the binding between the antibody moiety and sclerostin is greater than about either 10 ^-7M、10^-8M、10^-9M、10^-10M、10^-11 M or 10 ^-12 M. In some embodiments, the sclerostin is human sclerostin and/or the RANKL is human RANKL. In some embodiments, the sclerostin is cynomolgus monkey sclerostin.

In some embodiments, the K _on for the binding between the antibody moiety and sclerostin and/or RANKL is from about 10 ³M^- ¹s^-1 to about 10 ⁸M^-1s^-1, from about 10 ³M^-1s^-1 to about 10 ⁴M^-1s^-1, from about 10 ⁴M^-1s^-1 to about 10 ⁵M^-1s^-1, from about 10 ⁵M^-1s^-1 to about 10 ⁶M^- ¹s^-1, from about 10 ⁶M^-1s^-1 to about 10 ⁷M^-1s^-1, or from about 10 ⁷M^-1s^-1 to about 10 ⁸M^-1s^-1. In some embodiments, the K _on for binding between the antibody moiety and the sclerostin is about 10 ³M^-1s^-1 to about 10 ⁵M^-1s^-1, about 10 ⁴M^-1s^-1 to about 10 ⁶M^-1s^-1, about 10 ⁵M^-1s^-1 to about 10 ⁷M^-1s^-1, about 10 ⁶M^-1s^-1 to about 10 ⁸M^-1s^-1, about 10 ⁴M^-1s^-1 to about 10 ⁷M^-1s^-1, or about 10 ⁵M^-1s^-1 to about 10 ⁸M^-1s^-1. In some embodiments, the K _on of the binding between the antibody moiety and sclerostin does not exceed either about 10³M^-1s^-1、10⁴M^-1s^-1、10⁵M^-1s^-1、10⁶M^-1s^-1、10⁷M^-1s^-1 or 10 ⁸M^-1s^-1. In some embodiments, the sclerostin is human sclerostin and/or the RANKL is human RANKL. In some embodiments, the sclerostin is cynomolgus monkey sclerostin.

In some embodiments, the K _off for binding between the antibody moiety and sclerostin and/or RANKL is from about 1s ^-1 to about 10 ^-6s^-1, from about 1s ^-1 to about 10 ^-2s^-1, from about 10 ^-2s^-1 to about 10 ^-3s^-1, from about 10 ^-3s^-1 to about 10 ^-4s^-1, from about 10 ^-4s^-1 to about 10 ^- ⁵s^-1, from about 10 ^-5s^-1 to about 10 ^-6s^-1, from about 1s ^-1 to about 10 ^-5s^-1, About 10 ^-2s^-1 to about 10 ^-6s^-1, about 10 ^-3s^-1 to about 10 ^-6s^-1, about 10 ^-4s^-1 to about 10 ^-6s^-1, about 10 ^-2s^-1 to about 10 ^-5s^-1, or about 10 ^-3s^-1 to about 10 ^-5s^-1. In some embodiments, the Koff of the binding between the antibody moiety and sclerostin and/or RANKL is at least about any one of 1s ^-1、10^-2s^-1、10^-3s^-1、10^-4s^-1、10^-5s^-1 or 10 ^-6s^-1. In some embodiments, the sclerostin and/or RANKL is human RANKL or human sclerostin. In some embodiments, the sclerostin is cynomolgus monkey sclerostin.

In some embodiments, the binding affinity of the anti-sclerostin antibody portion and/or the anti-RANKL antibody portion or bispecific construct is higher (e.g., has a smaller KD value) than the existing anti-sclerostin antibody (e.g., luo Moshan antibodies).

B) Chimeric or humanized antibodies

In some embodiments, the bispecific construct (e.g., an anti-sclerostin antibody moiety) is a chimeric antibody. Certain chimeric antibodies are described. In some embodiments, the chimeric antibody comprises a non-human variable region (e.g., a mouse-derived variable region) and a human constant region. In some embodiments, the chimeric antibody is a "class switch" antibody, wherein a class or subclass has been switched from the class of the parent antibody. Chimeric antibodies include antigen-binding fragments thereof.

In some embodiments, the bispecific construct (e.g., an anti-sclerostin antibody moiety) is a humanized antibody. Typically, the non-human antibodies are humanized to reduce immunogenicity to humans while maintaining the specificity and affinity of the parent non-human antibody. Typically, a humanized antibody comprises one or more variable domains in which the HVRs, e.g., CDRs (or portions thereof) are derived from a non-human antibody and the FRs (or portions thereof) are derived from a human antibody sequence. The humanized antibody optionally comprises at least a portion of a human constant region. In some embodiments, some FR residues in a humanized antibody are substituted with corresponding residues from a non-human antibody (e.g., an antibody from which HVR residues are derived), e.g., to restore or improve antibody specificity or affinity.

Human framework regions useful for humanization include, but are not limited to: a framework region selected using a "best fit" method; framework regions derived from consensus sequences of human antibodies of a particular subset of light or heavy chain variable regions; human mature (somatic mutation) framework regions or human germline framework regions; framework regions from screening FR libraries.

It will be appreciated that humanisation of mouse derived antibodies is a common and routinely used technique. Thus, it is understood that the humanized structural forms of any and all of the anti-sclerostin antibodies disclosed in the sequence listing may be used in a preclinical or clinical setting. If any humanized structural form of an anti-sclerostin antibody or antigen-binding region thereof is used in such a preclinical or clinical setting, the humanized form is expected to have the same or similar biological activity and properties as the original non-humanized structural form.

C) Human antibodies

In some embodiments, the bispecific construct (e.g., an anti-sclerostin antibody moiety) is a human antibody (referred to as a human domain antibody or a human dAb). Various techniques known in the art may be used to produce human antibodies.

Human antibodies (e.g., human dabs) can be prepared by administering an immunogen to a transgenic animal that has been modified to produce a fully human antibody or a fully antibody having a human variable region that is responsive to antigen challenge. These animals typically include all or part of the human immunoglobulin loci that replace endogenous immunoglobulin loci, either present extrachromosomally or randomly integrated into the animal chromosome. In such transgenic mice, the endogenous immunoglobulin loci have typically been inactivated. The human variable regions of the whole antibodies produced by these animals may be further modified, for example by combining with different human constant regions.

Human antibodies (e.g., fv clone variable domain sequences selected from phage display libraries of human origin to produce human antibodies (e.g., human dabs). Such variable domain sequences can then be combined with desired human constant domains. Techniques for selecting human antibodies from antibody libraries are described below.

D) Library derived antibodies

The anti-sclerostin antibody portions described herein can be isolated by screening a combinatorial library of antibodies having the desired activity. For example, a variety of methods are known in the art for generating phage display libraries and screening those libraries for antibodies having the desired binding characteristics.

In some phage display methods, all components of the V _H and V _L genes are cloned by Polymerase Chain Reaction (PCR) and randomly recombined into phage libraries, and then screened for phage binding to antigen. Phage typically display antibody fragments in the form of scFv fragments or Fab fragments. Libraries from immunogens provide high affinity antibodies to immunogens without the need to construct hybridomas. Alternatively, the original repertoire (e.g., from a human) may be cloned to provide a single source of antibodies against multiple non-self and self-antigens without any immunization. Finally, natural libraries can also be prepared synthetically by cloning unrearranged V-gene fragments from stem cells, and encoding highly variable CDR3 regions using PCR primers comprising random sequences and completing the rearrangement in vitro.

Antibodies or antibody fragments isolated from a human antibody library are considered herein to be human antibodies or human antibody fragments.

E) Substitutions, insertions, deletions and variants

In some embodiments, antibody variants having one or more amino acid substitutions are provided. Sites of interest for substitution mutagenesis include HVRs (or CDRs) and FRs. Conservative substitutions are shown under the heading of "preferred substitutions" in table 2. More substantial changes are provided under the heading of "exemplary substitutions" in table 2, and as further described below with respect to the amino acid side chain class. Amino acid substitutions may be introduced into the antibody of interest and products of the desired activity selected, e.g., to retain/improve antigen binding, reduce immunogenicity or improve ADCC or CDC.

TABLE 2 amino acid substitutions

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Amino acids can be grouped according to common side chain characteristics: (1) hydrophobic: norleucine Met, ala, val, leu, ile; (2) neutral hydrophilicity: cys, ser, thr, asn, gln; (3) acidity: asp, glu; (4) alkaline: his, lys, arg; (5) residues that affect chain orientation: gly, pro; and (6) aromatic: trp, tyr, phe.

Non-conservative substitutions will require the exchange of members of one of these classes for another class.

One type of substitution variant involves substitution of one or more hypervariable region residues of a parent antibody (e.g., a humanized or human antibody). Typically, the resulting variants selected for further investigation will have modifications (e.g., improvements) in certain biological properties (e.g., increased affinity, reduced immunogenicity) and/or will substantially retain certain biological properties of the parent antibody relative to the parent antibody. Exemplary surrogate variants are affinity matured antibodies, which can be conveniently generated, for example, using phage display-based affinity maturation techniques, such as those described herein. Briefly, one or more HVR residues are mutated and variant antibodies are displayed on phage and screened for a particular biological activity (e.g., binding affinity).

Alterations (e.g., substitutions) may be made in the HVR, for example, to improve antibody affinity. Such changes may be made in HVR "hot spots", i.e. residues encoded by codons that undergo high frequency mutations during somatic maturation, and/or SDR (α -CDRs), wherein the resulting variants V _H or V _L are tested for binding affinity. Affinity maturation can be achieved by constructing and reselecting secondary libraries. In some embodiments of affinity maturation, diversity is introduced into the variable gene selected for maturation by any of a variety of methods (e.g., error-prone PCR, strand shuffling, or oligonucleotide-directed mutagenesis). A secondary library is then created. The library is then screened to identify any antibody variants with the desired affinity. Another approach to introducing diversity involves HVR-directed approaches in which several HVR residues (e.g., 4-6 residues at a time) are randomized. HVR residues involved in antigen binding can be specifically identified, for example, using alanine scanning mutagenesis or modeling. CDR-H3 and CDR-L3 are especially often targeted.

In some embodiments, substitutions, insertions, or deletions may occur within one or more HVRs, provided that such alterations do not substantially reduce the ability of the antibody to bind to an antigen. For example, conservative changes (e.g., conservative substitutions as provided herein) may be made in the HVR that do not substantially reduce binding affinity. Such changes are outside of the HVR "hot spot" or CDR.

A useful method for identifying antibody residues or regions that can be targeted for mutagenesis is referred to as "alanine scanning mutagenesis". In this method, a residue or set of target residues (e.g., charged residues such as Arg, asp, his, lys and Glu) are identified and replaced with neutral or negatively charged amino acids (e.g., alanine or polyalanine) to determine whether the interaction of the antibody with the antigen is affected. Further substitutions may be introduced at amino acid positions, demonstrating functional sensitivity to the initial substitutions. Alternatively or additionally, the crystal structure of the antigen-antibody complex at the contact point between the antibody and the antigen is identified. Such contact residues and neighboring residues may be targeted or eliminated as candidates for substitution. Variants may be screened to determine whether they include the desired properties.

Amino acid sequence insertions include amino and/or carboxy-terminal fusions ranging from one residue to polypeptide lengths comprising one hundred or more residues, as well as intrasequence insertions of single or multiple amino acid residues. Examples of terminal insertions include antibodies with an N-terminal methionyl residue. Other insertional variants of antibody molecules include fusion of the N-or C-terminus of an antibody with an enzyme (e.g., for ADEPT) or polypeptide that increases the serum half-life of the antibody.

F) Glycosylation variants

In some embodiments, bispecific constructs (e.g., anti-sclerostin antibody moieties) are altered to increase or decrease the extent of glycosylation of the construct. The addition or deletion of an antibody glycosylation site can be conveniently accomplished by altering the amino acid sequence so as to create or remove one or more glycosylation sites.

When the antibody moiety includes an Fc region, the sugar to which it is attached may be altered. Natural antibodies produced by mammalian cells typically include branched double-antennary oligosaccharides, which are typically linked by an N-bond to Asn297 of the C _H 2 domain of the Fc region. Oligosaccharides may include various carbohydrates such as mannose, N-acetylglucosamine (GlcNAc) \galactose and sialic acid, as well as fucose linked to GlcNAc in the "stem" of a double-antennary oligosaccharide structure. In some embodiments, oligosaccharides in the antibody moiety may be modified to produce antibody variants with certain improved properties.

In some embodiments, the bispecific construct (e.g., an anti-sclerostin antibody moiety) has a carbohydrate structure lacking fucose linked (directly or indirectly) to the Fc region. For example, the amount of fucose in such antibodies may be 1% to 80%, 1% to 65%, 5% to 65%, or 20% to 40%. The amount of fucose is determined by calculating the average amount of fucose within the sugar chains at Asn297 relative to the sum of all sugar structures (e.g. complex, hybrid and high mannose structures) attached to Asn297, as measured by MALDI-TOF mass spectrometry, for example as in WO 2008/077546. Asn297 refers to an asparagine residue at about position 297 in the Fc region (EU numbering of Fc region residues); however, asn297 may also be located about ±3 amino acids upstream or downstream of position 297, i.e. between 294 and 300, due to minor sequence variations in antibodies. Such fucosylated variants may have improved ADCC function. See, for example, U.S. patent publication US2003/0157108 (Presta, l.); US 2004/0093621 (Kyowa Hakko Kogyo co., ltd). Examples of publications related to "defucosylation" or "fucose deficient" antibody variants include ：US 2003/0157108;WO 2000/61739;WO 2001/29246;US 2003/0115614;US 2002/0164328;US 2004/0093621;US 2004/0132140;US 2004/0110704;US 2004/0110282;US 2004/0109865;WO 2003/085119;WO 2003/084570;WO 2005/035586;WO 2005/035778;WO 2005/053742;WO 2002/031140. examples of cell lines capable of producing fucosylated antibodies include Lec13 CHO cells lacking protein fucosylation (U.S. patent application US2003/0157108 A1,Presta,L; and WO 2004/056312 a1, adams et al, in particular example 11), and knockout cell lines such as the alpha-1, 6-fucosyltransferase gene, FUT8, knockout CHO cells (WO 2003/085107).

In some embodiments, the bispecific construct (e.g., an anti-sclerostin antibody moiety) has an bisecting oligosaccharide, e.g., a double antennary oligosaccharide wherein the antibody Fc region is bisected by GlcNAc. Such antibody variants may have reduced fucosylation and/or improved ADCC function. Examples of such antibody variants are described, for example, in WO 2003/011878 (Jean-Maiset et al); U.S. Pat. No. 6,602,684 (Umana et al); and US 2005/0123946 (Umana et al). Also provided are antibody variants having at least one galactose residue in the oligosaccharide attached to the Fc region. Such antibody variants may have improved CDC function. Such antibody variants are described, for example, in WO 1997/30087 (Patel et al); WO 1998/58964 (Raju, s.); and WO 1999/22764 (Raju, S.).

G) Fc region variants and light chain constant region variants

In some embodiments, the bispecific construct (e.g., an anti-sclerostin antibody moiety) comprises an Fc fragment.

The terms "Fc region", "Fc domain", "Fc fragment" or "Fc" refer to the C-terminal non-antigen binding region of an immunoglobulin heavy chain that includes at least a portion of a constant region. The term includes both native and variant Fc regions. In some embodiments, the human IgG heavy chain Fc region extends from Cys226 to the carboxy terminus of the heavy chain. However, the C-terminal lysine (Lys 447) of the Fc region may or may not be present without affecting the structure or stability of the Fc region. Unless otherwise indicated herein, numbering of amino acid residues in an IgG or Fc region is according to the EU numbering system of antibodies, also known as the EU index, e.g., kabat et al, protein sequence of immunological significance (Sequences of Proteins of Immunological Interest), 5 th edition, public health agency, national institutes of health, bethesda, MD,1991.

In some embodiments, the Fc fragment is from a group selected from: igG, igA, igD, igE, igM and combinations and hybrids thereof. In some embodiments, the Fc fragment is from an immunoglobulin selected from the group consisting of IgG1, igG2, igG3, igG4, and combinations and hybrids thereof.

In some embodiments, the Fc fragment has reduced effector function (e.g., at least about 30%, 40%, 50%, 60%, 70%, 80%, 85%, 90%, or 95% reduced effector function as measured by Antibody Dependent Cellular Cytotoxicity (ADCC) levels) as compared to a corresponding wild-type Fc fragment.

In some embodiments, the Fc fragment is an IgG1Fc fragment. In some embodiments, the IgG1Fc fragment comprises an L234A mutation and/or an L235A mutation. In some embodiments, the Fc fragment is an IgG2 or IgG4 Fc fragment. In some embodiments, the Fc fragment is an IgG4 Fc fragment comprising the S228P, F234A and/or L235A mutation. In some embodiments, the Fc fragment comprises an N297A mutation. In some embodiments, the Fc fragment comprises an N297G variant.

In some embodiments, one or more amino acid modifications may be introduced into the Fc region of the antibody portion, thereby producing an Fc region variant. The Fc region variant may include a human Fc region sequence (e.g., a human IgG1, igG2, igG3, or IgG4 Fc region) that includes amino acid modifications (e.g., substitutions) at one or more amino acid positions. In some embodiments, the Fc fragment is derived from a rat Fc region sequence (e.g., a rat IgG2 Fc) or a mouse Fc region sequence (e.g., a mouse IgG1 Fc).

In some embodiments, the Fc fragment comprises a human IgG2 Fc region.

In some embodiments, the Fc fragment comprises a human IgG4 Fc region. In some embodiments, the Fc fragment comprises a modified human IgG4 heavy chain Fc region comprising one or more (e.g., two, three, or four) substitutions selected from S228P, T W and optionally H435R and optionally Y436F. Unless otherwise indicated, the numbering of the modifications described herein is according to the EU index. In some embodiments, the Fc fragment comprises a modified human IgG4 heavy chain Fc region comprising S228P, T366W and optionally H435R and optionally Y436F. In some embodiments, the Fc fragment comprises a modified human IgG4 heavy chain Fc region comprising one or more (e.g., two, three, four, five, or six) substitutions selected from F126C, L128C, C131S, F170C, P161C, V173C, S228P, T366S, L a and Y407V, and optionally H435R and optionally Y436F. In some embodiments, the Fc fragment comprises a modified human IgG4 heavy chain Fc region comprising a) C131S, S228P, T366S, L368A and Y407V, and b) one of the substitutions selected from F126C, L128C, F170C, P161C and V173C, and C) optionally H435R and optionally Y436F. In some embodiments, the Fc fragment comprises a modified human IgG4 heavy chain Fc region comprising one or more (e.g., two, three, four, five, or six) substitutions selected from F126C, C131S, S228P, T366S, L368A and Y407V, and optionally H435R and optionally Y436F. In some embodiments, the Fc fragment comprises a modified human IgG4 heavy chain Fc region comprising F126C, C131S, S228P, T366S, L a and Y407V, and optionally H435R and optionally Y436F. In some embodiments, the Fc fragment comprises a modified human IgG4 heavy chain Fc region comprising L128C, C131S, S228P, T366S, L368A and Y407V, and optionally H435R and optionally Y436F. In some embodiments, the Fc fragment comprises a modified human IgG4 heavy chain Fc region comprising C131S, F170C, S228P, T366S, L a and Y407V, and optionally H435R and optionally Y436F. In some embodiments, the Fc fragment comprises a modified human IgG4 heavy chain Fc region comprising C131S, V173C, S228P, T366S, L368A and Y407V, and optionally H435R and optionally Y436F. In some embodiments, the Fc fragment comprises a modified human IgG4 heavy chain Fc region comprising C131S, P171C, S228P, T366S, L368A and Y407V, and optionally H435R and optionally Y436F.

In some embodiments, the bispecific construct comprises an Fc fragment comprising a) a first modified human IgG4 heavy chain Fc region comprising S228P, T366W, and b) a second modified human IgG4 heavy chain Fc region comprising a) C131S, S228P, T366S, L a and Y407V, and optionally H435R and optionally Y436F, and b) one of the substitutions selected from F126C, L128C, F C, P161C and V173C.

In some embodiments, the bispecific construct comprises an Fc fragment comprising a) a first modified human IgG4 heavy chain Fc region comprising S228P, T366W, and b) a second modified human IgG4 heavy chain Fc region comprising F126C, C131S, S228P, T366S, L A, Y407V, H R and Y436F.

In some embodiments, the bispecific construct comprises an Fc fragment comprising a) a first modified human IgG4 heavy chain Fc region comprising S228P, T366W, and b) a second modified human IgG4 heavy chain Fc region comprising L128C, C131S, S228P, T366S, L A, Y407V, H R and Y436F.

In some embodiments, the bispecific construct comprises an Fc fragment comprising a) a first modified human IgG4 heavy chain Fc region comprising S228P, T366W, and b) a second modified human IgG4 heavy chain Fc region comprising C131S, F170C, S228P, T366S, L A, Y407V, H R and Y436F.

In some embodiments, the bispecific construct comprises an Fc fragment comprising a) a first modified human IgG4 heavy chain Fc region comprising S228P, T366W, and b) a second modified human IgG4 heavy chain Fc region comprising C131S, V173C, S228P, T366S, L A, Y407V, H R and Y436F.

In some embodiments, the bispecific construct comprises an Fc fragment comprising a) a first modified human IgG4 heavy chain Fc region comprising S228P, T366W, and b) a second modified human IgG4 heavy chain Fc region comprising C131S, P171C, S228P, T366S, L A, Y407V, H R and Y436F.

In some embodiments, the bispecific construct comprises a human igkappa light chain constant region. In some embodiments, the bispecific construct comprises a modified human Ig kappa light chain constant region comprising F118C, S121C, Q160C, S162C, S176C and/or C214S. In some embodiments, the bispecific construct comprises a modified human igkappa light chain constant region comprising S121C and C214S. In some embodiments, the bispecific construct comprises a modified human igkappa light chain constant region comprising F118C and C214S. In some embodiments, the bispecific construct comprises a modified human igkappa light chain constant region comprising S176C and C214S. In some embodiments, the bispecific construct comprises a modified human igkappa light chain constant region comprising Q160C and C214S. In some embodiments, the bispecific construct comprises a modified human igkappa light chain constant region comprising S162C and C214S.

In some embodiments, the Fc fragment has some, but not all, effector functions, making it an ideal candidate for applications where the half-life of the antibody moiety in vivo is important and certain effector functions (such as complement and ADCC) are unnecessary or detrimental. In vitro and/or in vivo cytotoxicity assays may be performed to confirm reduction/depletion of CDC and/or ADCC activity. For example, an Fc receptor (FcR) binding assay may be performed to ensure that the antibody lacks FcR binding (and thus may lack ADCC activity), but retains FcRn binding capacity. Primary cells mediating ADCC NK cells express fcyriii only, whereas monocytes express fcyri, fcyrii and fcyriii. Non-limiting examples of in vitro assays for assessing ADCC activity of a molecule of interest are described in U.S. patent No. 5,500,362. Alternatively, non-radioactive assays (see, e.g., ACTI ^TM flow cytometry, non-radioactive cytotoxicity assays (CellTechnology, inc.Mountain View, CA; andNon-radioactive cytotoxicity assay (Promega, madison, wis.). Effector cells useful in such assays include Peripheral Blood Mononuclear Cells (PBMC) and Natural Killer (NK) cells. Alternatively or additionally, ADCC activity of the target molecule may be assessed in vivo. A C1q binding assay may also be performed to confirm that the antibody is unable to bind C1q and thus lacks CDC activity. See, e.g., C1q and C3C binding ELISA in WO 2006/029879 and WO 2005/100402. To assess complement activation, CDC assays may be performed. FcRn binding and in vivo clearance/half-life assays may also be performed using methods known in the art.

Antibodies with reduced effector function include antibodies with one or more substitutions in Fc region residues 238, 265, 269, 270, 297, 327 and 329 (U.S. patent No. 6,737,056). Such Fc mutants include Fc mutants having substitutions at two or more of amino acid positions 265, 269, 270, 297 and 327, including so-called "DANA" Fc mutants in which residues 265 and 297 are substituted with alanine (U.S. Pat. No. 7,332,581). In some embodiments, the Fc fragment comprises an N297A mutation. In some embodiments, the Fc fragment comprises an N297G variant.

Certain antibody variants with improved or reduced binding to FcRs are described. ( See, for example, U.S. Pat. nos. 6,737,056; WO 2004/056312 )

In some embodiments, the Fc fragment is an IgG1 Fc fragment. In some embodiments, the IgG1 Fc fragment comprises an L234A mutation and/or an L235A mutation. In some embodiments, the Fc fragment is an IgG2 or IgG4 Fc fragment. In some embodiments, the Fc fragment is an IgG4 Fc fragment comprising the S228P, F234A and/or L235A mutation.

In some embodiments, the antibody moiety comprises an Fc region with one or more amino acid substitutions that improve ADCC, e.g., substitutions at positions 298, 333, and/or 334 of the Fc region (EU numbering of residues).

In some embodiments, the alteration in the Fc region results in altered (i.e., improved or reduced) C1q binding and/or Complement Dependent Cytotoxicity (CDC), e.g., as in U.S. patent No. 6,194,551, WO 99/51642.

In some embodiments, the antibody moiety variant comprises a variant Fc region comprising one or more amino acid substitutions that alter half-life and/or alter binding to neonatal Fc receptor (FcRn). Antibodies with increased half-lives and improved binding to neonatal Fc receptor (FcRn) responsible for transfer of maternal IgG to the fetus are described in US2005/0014934A1 (Hinton et al). These antibodies include an Fc region having one or more substitutions therein that alter the binding of the Fc region to FcRn. Such Fc variants include those having substitutions at one or more Fc region residues at positions 250, 252, 254, 256, 307, 308, 428, 434 (U.S. patent 7,371,826), including so-called "LS" Fc mutants comprising M428L and N434S (WO 2009/086320) and so-called "YTE" Fc mutants comprising M252Y, S T and T256E (WO 2002/060919).

See also U.S. Pat. nos. 5,648,260; U.S. Pat. No. 5,624,821; WO 94/29351 relates to other examples of variants of the Fc region.

H) Cysteine engineered antibody variants

In some embodiments, it may be desirable to generate cysteine engineered antibody moieties, such as "thioMAbs", in which one or more residues of the antibody are substituted with cysteine residues. In certain embodiments, the substituted residue occurs at an accessible site of the antibody. By replacing those residues with cysteines, reactive thiol groups are thus located at accessible sites of the antibody, and can be used to conjugate the antibody to other moieties, such as drug moieties or linker-drug moieties, to produce antibody-drug conjugates, as described further herein. In some embodiments, any one or more of the following residues may be substituted with a cysteine: a118 (EU numbering) of heavy chain; and S400 (EU numbering) of the heavy chain Fc region. Cysteine engineered antibody moieties may be produced as in, for example, U.S. patent 7,521,541.

I) Antibody derivatives

In some embodiments, the antibody moieties described herein can be further modified to include additional non-protein moieties known and readily available in the art. Moieties suitable for derivatization of antibodies include, but are not limited to, water-soluble polymers. Non-limiting examples of water soluble polymers include, but are not limited to, polyethylene glycol (PEG), ethylene glycol/propylene glycol copolymers, carboxymethyl cellulose, dextran, polyvinyl alcohol, polyvinylpyrrolidone, poly-1, 3-dioxolane, poly-1, 3, 6-trioxane, ethylene/maleic anhydride copolymers, polyaminoacids (homo-or random copolymers) and dextran or poly (n-vinylpyrrolidone) polyethylene glycol, propylene glycol homopolymers, polypropylene oxide/ethylene oxide copolymers, polyoxyethylated polyols (e.g., glycerol), polyvinyl alcohol, and mixtures thereof. Polyethylene glycol propionaldehyde has advantages in manufacturing due to its stability in water. The polymer may have any molecular weight and may be branched or unbranched. The number of polymers attached to the antibody may vary, and if more than one polymer is attached, they may be the same or different molecules. In general, the number and/or type of polymers used for derivatization may be determined based on considerations including, but not limited to, the particular properties or functions of the antibody to be improved, whether the antibody derivative will be used for diagnosis under defined conditions, and the like.

In some embodiments, the antibody moiety may be further modified to include one or more biologically active proteins, polypeptides, or fragments thereof. As used interchangeably herein, "bioactive" or "bioactive" means that the bioactivity is exhibited in vivo to perform a particular function. For example, it may refer to a combination with a specific biomolecule such as a protein, DNA, etc., and then promote or inhibit the activity of such a biomolecule. In some embodiments, the biologically active protein or fragment thereof includes proteins and polypeptides administered to a patient as active pharmaceutical substances for preventing or treating a disease or condition, as well as proteins and polypeptides for diagnostic purposes, such as enzymes for diagnostic testing or in vitro assays, and proteins and polypeptides administered to a patient to prevent a disease, such as a vaccine.

Bispecific fusion proteins or antibody-drug conjugates

In some embodiments, the bispecific construct is a fusion protein or antibody-drug conjugate comprising an anti-sclerostin antibody moiety (e.g., an anti-sclerostin scFv) and a second moiety (e.g., an anti-RANKL SCFV).

In some embodiments, the second moiety comprises a half-life extending moiety. In some embodiments, the half-life extending moiety is an albumin binding moiety (e.g., an albumin binding antibody moiety).

In some embodiments, the second moiety comprises an agent selected from the group consisting of parathyroid hormone (PTH), selective Estrogen Receptor Modulator (SERM), bisphosphonate, prostaglandin E (PGE) receptor agonist, VEGF, tgfβ, growth factor (myostatin), and calcitonin.

In some embodiments, the anti-sclerostin antibody moiety and the second moiety are fused by a linker (e.g., any of the linkers described in the "linker" moiety). In some embodiments, the anti-sclerostin antibody moiety and the second moiety are not fused by a linker.

Joint

In some embodiments, the bispecific constructs described herein include one or more linkers between two moieties (e.g., an anti-sclerostin antibody moiety and a half-life extending moiety, an anti-sclerostin antibody moiety and a second binding moiety in the multispecific constructs described above). The length, degree of flexibility, and/or other properties of the linker for the anti-sclerostin construct may have some effect on properties, including but not limited to affinity, specificity, or avidity for one or more particular antigens or epitopes. For example, longer linkers can be selected to ensure that two adjacent domains do not spatially interfere with each other. In some embodiments, the linker (e.g., peptide linker) includes flexible residues (e.g., glycine and serine) such that adjacent domains are free to move relative to each other. For example, glycine-serine duplex may be a suitable peptide linker. In some embodiments, the linker is a non-peptide linker. In some embodiments, the linker is a peptide linker. In some embodiments, the linker is a non-cleavable linker. In some embodiments, the linker is a cleavable linker.

Other linker considerations include effects on the physical or pharmacokinetic properties of the resulting compound, such as solubility, lipophilicity, hydrophilicity, hydrophobicity, stability (more or less stable and planned degradation), rigidity, flexibility, immunogenicity, modulation of antibody binding, ability to incorporate micelles or liposomes, and the like.

Peptide linker

The peptide linker may have a naturally occurring sequence or a non-naturally occurring sequence. For example, sequences from the hinge region of heavy chain-only antibodies may be used as linkers.

The peptide linker may be of any suitable length. In some embodiments, the peptide linker is at least about any one of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 25, 30, 35, 40, 50, 75, 100, or more amino acids in length. In some embodiments, the peptide linker is no more than about any one of 100, 75, 50, 40, 35, 30, 25, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, or less amino acids in length. In some embodiments, the peptide linker is any of about 1 amino acid to about 10 amino acids, about 1 amino acid to about 20 amino acids, about 1 amino acid to about 30 amino acids, about 5 amino acids to about 15 amino acids, about 10 amino acids to about 25 amino acids, about 5 amino acids to about 30 amino acids, about 10 amino acids to about 30 amino acids long, about 30 amino acids to about 50 amino acids, about 50 amino acids to about 100 amino acids, or about 1 amino acid to about 100 amino acids in length.

The basic technical feature of such peptide linkers is that the peptide linker does not include any polymerization activity. Features of peptide linkers, including not promoting secondary structures, are known and described in the art. In the context of "peptide linkers", a particularly preferred amino acid is Gly. In addition, peptide linkers that do not promote any secondary structure are preferred. The linking of domains to each other may be provided by, for example, genetic engineering. Methods for preparing fused and operatively linked bispecific single chain constructs and expressing them in mammalian cells or bacteria are well known in the art.

The peptide linker may be a stable linker that is not cleavable by proteases, particularly Matrix Metalloproteinases (MMPs).

The joint may also be a flexible joint. Exemplary flexible linkers include glycine polymer (G) _n (SEQ ID NO: 19), glycine-serine polymers (including, for example, (GS) _n(SEQ ID NO：20)、(GSGGS)_n(SEQ ID NO：21)、(GGGGS)_n (SEQ ID NO: 22) and (GGGS) _n (SEQ ID NO: 23), where n is an integer of at least 1), glycine-alanine polymers, alanine-serine polymers, and other flexible linkers known in the art. Glycine and glycine-serine polymers are relatively unstructured and therefore can be used as neutral tethers between components. Glycine enters significantly more phi-psi space than alanine and is less limiting than residues with longer side chains. One of ordinary skill in the art will recognize that the design of an antibody fusion protein may include a linker that is wholly or partially flexible, such that the linker may include a flexible linker portion as well as one or more portions that impart a less flexible structure to provide the desired antibody fusion protein structure.

In addition, exemplary linkers also include amino acid sequences such as (GGGGS) _n (SEQ ID NO: 22), where n is an integer from 1 to 8, e.g., (GGGGS) ₃(SEQ ID NO：17)、(GGGGS)₄ (SEQ ID NO: 18) or (GGGGS) ₆ (SEQ ID NO: 24). In some embodiments, the peptide linker comprises the amino acid sequence of (GSTSGSGKPGSGEGS) _n (SEQ ID NO: 25), wherein n is an integer from 1 to 3.

Non-peptide linker

The coupling of the two moieties may be achieved by any chemical reaction that will bind the two molecules, provided that the two components retain their respective activities, e.g., the sclerostin and the second agent, respectively, that bind to the anti-sclerostin multispecific antibody. Such attachment may include a number of chemical mechanisms, such as covalent binding, affinity binding, intercalation, coordination binding, and complexation. In some embodiments, the binding is covalent. Covalent binding may be achieved by direct condensation of existing side chains or by the introduction of external bridge molecules. In this context, a number of bivalent or multivalent linkers may be used to couple protein molecules. For example, representative coupling agents may include organic compounds such as thioesters, carbodiimides, succinimidyl esters, diisocyanates, glutaraldehyde, diazobenzenes, and hexamethylenediamine. This list is not intended to be exhaustive of the various types of coupling agents known in the art, but rather examples of more common coupling agents.

In some embodiments, the non-peptide linkers used herein include: (i) EDC (1-ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride, (ii) SMPT (4-succinimidyloxycarbonyl- α -methyl- α - (2-pyridinyl-dithio) -toluene (Pierce chem. Co., cat. No. 21558G), (iii) SPDP (succinimidyl-6[3- (2-pyridinyl dithio) propionylamino ] hexanoate (Pierce chem. Co., cat. No. 21651G)), and (iv) thio-LC-SPDP (sulfosuccinimidyl 6[3- (2-pyridinyl dithio) -propionamide ] hexanoate (Pierce chem. Co., cat. No. 2165-G), and (v) thiocnhs (N-hydroxythiosuccinimide: pierce chem. Co., cat. No. 24510) conjugated to EDC.

The above-described linker comprises components having different properties, and thus bispecific antibodies having different physicochemical properties can be produced. For example, the sulfo-NHS ester of an alkyl carboxylate is more stable than the sulfo-NHS ester of an aromatic carboxylate. The solubility of the linker comprising the NHS-ester is lower than the sulfo-NHS ester. In addition, linker SMPT includes a sterically hindered disulfide bond and can form an antibody fusion protein with increased stability. Disulfide bonds are generally less stable than other bonds because disulfide bonds are cleaved in vitro, resulting in fewer antibody fusion proteins being available. In particular, sulfo-NHS may enhance the stability of carbodiimide coupling. When used in combination with sulfo-NHS, carbodiimide coupling (e.g., EDC) forms esters that are more resistant to hydrolysis than carbodiimide coupling reactions alone.

III preparation method

In some embodiments, methods of making bispecific constructs or antibody portions that specifically bind to sclerostin and a second antigen are provided, as well as compositions such as polynucleotides, nucleic acid constructs, vectors, host cells, or culture media produced during the preparation of the bispecific constructs or antibody portions. Bispecific constructs or antibody moieties or compositions described herein can be prepared by a number of methods as generally described below and more specifically described in the examples.

Antibody expression and production

The antibodies described herein (including anti-sclerostin bispecific antibodies, anti-sclerostin antibody portions and anti-RANKL antibody portions) can be prepared using any method known in the art, including those described below and in the examples.

Nucleic acid molecules encoding antibody moieties

In some embodiments, polynucleotides encoding any of the bispecific constructs or antibody portions described herein are provided. In some embodiments, polynucleotides prepared using any of the methods described herein are provided. In some embodiments, the nucleic acid molecule comprises a polynucleotide encoding a heavy or light chain of an antibody moiety (e.g., an anti-sclerostin antibody moiety). In some embodiments, the nucleic acid molecule includes both a polynucleotide encoding the heavy chain and a polynucleotide encoding the light chain of an antibody moiety (e.g., an anti-sclerostin antibody moiety). In some embodiments, the first nucleic acid molecule comprises a first polynucleotide encoding a heavy chain and the second nucleic acid molecule comprises a second polynucleotide encoding a light chain.

In some such embodiments, the heavy and light chains are expressed from one nucleic acid molecule, or from two separate nucleic acid molecules as two separate polypeptides. In some embodiments, for example when the antibody is an scFv, the single polynucleotide encodes a single polypeptide comprising a heavy chain and a light chain linked together.

In some embodiments, the polynucleotide encoding the heavy or light chain of an antibody moiety (e.g., an anti-sclerostin antibody moiety) includes a nucleotide sequence encoding a leader sequence that is located N-terminal to the heavy or light chain upon translation. As described above, the leader sequence may be a natural heavy or light chain leader sequence, or may be another heterologous leader sequence.

In some embodiments, the polynucleotide is DNA. In some embodiments, the polynucleotide is RNA. In some embodiments, the RNA is mRNA.

Nucleic acid molecules can be constructed using recombinant DNA techniques conventional in the art. In some embodiments, the nucleic acid molecule is an expression vector (vector) suitable for expression in a selected host cell.

Nucleic acid constructs

In some embodiments, nucleic acid constructs comprising any of the polynucleotides described herein are provided. In some embodiments, nucleic acid constructs prepared using any of the methods described herein are provided.

In some embodiments, the nucleic acid construct further comprises a promoter operably linked to the polynucleotide. In some embodiments, the polynucleotide corresponds to a gene, wherein the promoter is a wild-type promoter of the gene.

Carrier (vector)

In some embodiments, vectors (vectors) comprising any polynucleotide encoding the heavy and/or light chain of any one of the antibody moieties described herein (e.g., an anti-sclerostin antibody moiety) or a nucleic acid construct herein are provided. In some embodiments, vectors prepared using any of the methods described herein are provided. Also provided are vectors comprising polynucleotides encoding any bispecific constructs such as antibodies, scFv, fusion proteins, or other forms of constructs described herein (e.g., anti-sclerostin scFv). Such vectors (vectors) include, but are not limited to, DNA vectors (vectors), phage vectors (vectors), viral vectors (vectors), retroviral vectors (vectors), and the like. In some embodiments, the vector (vector) comprises a first polynucleotide sequence encoding a heavy chain and a second polynucleotide sequence encoding a light chain. In some embodiments, the heavy and light chains are expressed from a vector (vector) as two separate polypeptides. In some embodiments, the heavy and light chains are expressed as part of a single polypeptide, for example when the antibody is an scFv.

In some embodiments, the first vector (vector) comprises a polynucleotide encoding a heavy chain and the second vector (vector) comprises a polynucleotide encoding a light chain. In some embodiments, the first vector (vector) and the second vector (vector) are transfected into the host cell in similar amounts (e.g., similar molar amounts or similar masses). In some embodiments, a first vector (vector) and a second vector (vector) in a molar ratio or mass ratio of 5:1 to 1:5 are transfected into a host cell. In some embodiments, a mass ratio of vector encoding a heavy chain (vector) to vector encoding a light chain (vector) is used that is between 1:1 and 1:5. In some embodiments, a mass ratio of vector encoding a heavy chain (vector) to vector encoding a light chain (vector) is used of 1:2.

In some embodiments, a vector optimized to express the polypeptide in CHO or CHO-derived cells or NS0 cells is selected.

Host cells

In some embodiments, host cells are provided that include any of the polypeptides, nucleic acid constructs, and/or vectors (vectors) described herein. In some embodiments, host cells prepared using any of the methods described herein are provided. In some embodiments, the host cell is capable of producing any of the antibody moieties described herein under fermentation conditions.

In some embodiments, an antibody moiety described herein (e.g., an anti-sclerostin antibody moiety) can be expressed in a prokaryotic cell, such as a bacterial cell; or in eukaryotic cells, such as fungal cells (e.g., yeast), plant cells, insect cells, and mammalian cells. Such expression may be performed, for example, according to methods known in the art. Exemplary eukaryotic cells that can be used to express the polypeptide include, but are not limited to, COS cells, including COS 7 cells; 293 cells, including 293-6E cells; CHO cells, including CHO-S, dg44.lec13 CHO cells, and FUT8 CHO cells; Cells (Crucell); and NS0 cells. In some embodiments, an antibody moiety described herein (e.g., an anti-sclerostin antibody moiety) can be expressed in yeast. See, for example, U.S. publication No. US 2006/0270045 A1. In some embodiments, a particular eukaryotic host cell is selected based on its ability to make a desired post-translational modification of the heavy and/or light chain of the antibody moiety. For example, in some embodiments, CHO cells produce polypeptides having a higher level of sialylation than the same polypeptide produced in 293 cells.

The introduction of one or more nucleic acids into a desired host cell may be accomplished by any method including, but not limited to, calcium phosphate transfection, DEAE-dextran mediated transfection, cationic lipid-mediated transfection, electroporation, transduction, infection, and the like. The nucleic acid may be transiently or stably transfected in the desired host cell according to any suitable method.

The application also provides a host cell comprising any of the polynucleotides or vectors (vectors) described herein. In some embodiments, the application provides host cells comprising anti-sclerostin antibodies. Any host cell capable of overexpressing heterologous DNA may be used to isolate the gene encoding the antibody, polypeptide or protein of interest. Non-limiting examples of mammalian host cells include, but are not limited to, COS, heLa, and CHO cells. See also PCT publication WO 87/04462. Suitable non-mammalian host cells include prokaryotes (e.g., E.coli or B.subtilis) and yeast (e.g., saccharomyces cerevisiae, schizosaccharomyces, or Kluyveromyces lactis).

In some embodiments, the antibody moiety is produced in a cell-free system.

Culture medium

In some embodiments, a culture medium comprising any of the antibody portions, polynucleotides, nucleic acid constructs, vectors, and/or host cells described herein is provided. In some embodiments, a culture medium prepared using any of the methods described herein is provided.

In some embodiments, the medium comprises hypoxanthine, aminopterin, and/or thymidine (e.g., HAT medium). In some embodiments, the medium does not include serum. In some embodiments, the culture medium comprises serum. In some embodiments, the medium is D-MEM or RPMI-1640 medium.

Purification of antibody portions

Bispecific constructs (e.g., anti-sclerostin monoclonal antibodies or multispecific antibodies) can be purified by any suitable method. These methods include, but are not limited to, the use of affinity matrices or hydrophobic interaction chromatography. Suitable affinity ligands include ROR1 ECD and ligands that bind to the antibody constant region. For example, protein a, protein G, protein a/G, or antibody affinity columns may be used to bind to the constant region and purify the bispecific construct including the Fc fragment. Hydrophobic interaction chromatography, such as butyl or phenyl columns, may also be suitable for purifying some polypeptides, such as antibodies. Ion exchange chromatography (e.g., anion exchange chromatography and/or cation exchange chromatography) may also be useful for purifying some polypeptides such as antibodies. Mixed mode chromatography (e.g., reversed phase/anion exchange, reversed phase/cation exchange, hydrophilic interaction/anion exchange, hydrophilic interaction/cation exchange, etc.) may also be suitable for purifying some polypeptides such as antibodies. Many methods of purifying polypeptides are known in the art.

IV. method of treatment

In some embodiments, methods of treating a disease or condition in an individual are provided, comprising administering to the individual an effective amount of a bispecific construct or pharmaceutical composition described herein. In some embodiments, the disease or condition is a bone-related disorder or cartilage-related disorder, bone marrow or hematologic disorder, musculoskeletal rare disease, muscle-related disorder, or cancer.

The methods described herein are applicable to any bone-related disease or condition. In some embodiments, the bone-related disorder is osteogenesis imperfecta, osteoporosis or reduced bone mass (in men and/or women), osteonecrosis, delayed bone healing, non-union fractures, multiple myeloma-related bone disorders, primary bone tumors, bone metastases of malignant tumors, solid tumor bone metastases, inflammatory or infectious bone diseases, osteomalacia, hypercalcemia, paget's disease, brake-induced bone loss, glucocorticoid-induced bone loss, inflammation-induced bone loss including arthritis-induced bone loss, aerospace osteoporosis/osteopenia and bone loss due to gravity reduction or other diseases or conditions associated with: a) Bone loss in quantity or mass or both and/or b) abnormalities in bone structure and mass. In some embodiments, the bone-related disorder is osteoporosis or reduced bone mass. In some embodiments, the bone-related disorder is osteogenesis imperfecta. In some embodiments, the bone-related disorder is multiple myeloma and multiple myeloma-related bone disorders.

In some embodiments, the disease or condition is a cartilage disorder. In some embodiments, the cartilage disease is chondromatosis, cartilage dysplasia, cartilage hypoplasia, epiphyseal dysplasia, cartilage dystrophy myotonia, near cortical osteoma, knee cartilage tear, bone fibrodysplasia, osteoarthritis, osteogenesis imperfecta, hypophosphatemic rickets, or osteochondral dystrophy.

In some embodiments, the disease or condition is a muscle-related disorder. In some embodiments, the muscle-related disorder is sarcopenia and cancer sarcopenia.

In some embodiments, the disease or condition is cancer (e.g., hematological malignancy, such as multiple myeloma).

In some embodiments, methods of promoting healing after a bone or joint surgery in an individual are provided that include administering to the individual an effective amount of a bispecific construct (e.g., any of the bispecific constructs described herein).

In some embodiments, there is provided a method of treating a disease or condition (e.g., a bone-related disease) in an individual comprising administering to the individual an effective amount of a bispecific construct comprising an antibody portion comprising a heavy chain variable region (V _H) and a light chain variable region (V _L), wherein V _H comprises i) a polypeptide comprising SEQ ID NO:1, ii) an HC-CDR1 comprising the amino acid sequence of SEQ ID NO:2, and iii) an HC-CDR2 comprising the amino acid sequence of SEQ ID NO:3, or a variant thereof comprising up to 5, 4, 3, 2 or 1 amino acid substitutions in the HC-CDR, and V _L comprises i) an amino acid sequence comprising SEQ ID NO:4 or 26, ii) an LC-CDR1 comprising the amino acid sequence of SEQ ID NO:5, and iii) an LC-CDR2 comprising the amino acid sequence of SEQ ID NO:6, or a variant comprising up to 5, 4, 3, 2, or 1 amino acid substitutions in the LC-CDR.

In some embodiments, methods of treating a disease or condition (e.g., a bone-related disease) in an individual are provided that include administering to the individual an effective amount of a multispecific construct including a first antibody portion that specifically recognizes sclerostin and a second antibody portion that specifically recognizes RANKL. In some embodiments, the first antibody portion comprises a first heavy chain variable region (V _H-1) and a first light chain variable region (V _L-1), wherein V _H-1 comprises i) a light chain variable region comprising SEQ ID NO:1, ii) an HC-CDR1 comprising the amino acid sequence of SEQ ID NO:2, and iii) an HC-CDR2 comprising the amino acid sequence of SEQ ID NO:3, or a variant thereof comprising up to 5, 4, 3, 2 or 1 amino acid substitutions in the HC-CDR, and V _L-1 comprises i) an amino acid sequence comprising SEQ ID NO:4 or 26, ii) an LC-CDR1 comprising the amino acid sequence of SEQ ID NO:5, and iii) an LC-CDR2 comprising the amino acid sequence of SEQ ID NO:6, or a variant comprising up to 5, 4, 3, 2, or 1 amino acid substitutions in the LC-CDR. In some embodiments, the second antibody portion comprises a second heavy chain variable region (V _H-2) and a second light chain variable region (V _L-2), wherein V _H-2 comprises a polypeptide comprising SEQ ID NO:7, comprising the amino acid sequence of SEQ ID NO:8 and an HC-CDR2 comprising the amino acid sequence of SEQ ID NO:9, and V _L-2 comprises an HC-CDR3 comprising the amino acid sequence of SEQ ID NO:10, comprising the amino acid sequence of SEQ ID NO:11, comprising the amino acid sequence of SEQ ID NO:12, and LC-CDR3 of the amino acid sequence of seq id no.

In some embodiments, the subject is a mammal (e.g., a human).

Methods of administration and administration of bispecific constructs

The dosing regimen (e.g., specific dosages and frequencies) of the bispecific constructs administered to an individual for treating a disease or condition described herein can vary with the particular bispecific construct (e.g., anti-sclerostin monoclonal or multispecific antibody, e.g., anti-sclerostin fusion protein), the mode of administration, and the type of disease or condition being treated.

In some embodiments of any of the above aspects, the effective amount of the bispecific construct (e.g., an anti-sclerostin monoclonal or multispecific antibody) is in the range of about 0.001 μg/kg to about 500mg/kg total body weight, e.g., about 0.005 μg/kg to about 100mg/kg, about 0.01 μg/kg to about 50mg/kg, or about 0.01 μg/kg to about 5mg/kg.

In some embodiments, the treatment comprises more than one administration of the bispecific construct (e.g., about two, three, four, five, six, seven, eight, one night or ten administrations of the bispecific construct). In some embodiments, the bispecific construct is administered at a frequency of about daily, weekly, twice weekly, monthly, every three months, every six months, or yearly.

Bispecific constructs can be administered to an individual (e.g., a human) by a variety of routes including, for example, intravenous, intra-articular, intra-arterial, intraperitoneal, intrapulmonary, oral, inhalation, intravesical, intramuscular, intratracheal, subcutaneous, intraocular, intrathecal, transmucosal, and transdermal. In some embodiments, the bispecific construct is included in a pharmaceutical composition when administered to an individual. In some embodiments, a sustained continuous release formulation of the composition may be used. In some embodiments, the composition is administered intravenously. In some embodiments, the composition is administered intraperitoneally. In some embodiments, the composition is administered intravenously. In some embodiments, the composition is administered intraperitoneally. In some embodiments, the composition is administered intramuscularly. In some embodiments, the composition is administered subcutaneously. In some embodiments, the composition is administered intravenously. In some embodiments, the compound is administered orally.

Combination therapy

The application also provides methods of administering a bispecific construct to an individual to treat a disease or condition (e.g., a bone-related disease), wherein the method further comprises administering a second agent or therapy. In some embodiments, the second agent or therapy is a standard or common agent or therapy for treating a disease or condition.

In some embodiments, methods of treating a disease or condition (e.g., a bone-related disease) in an individual are provided, comprising administering to the individual a) an effective amount of a bispecific construct (e.g., any of the bispecific constructs described herein); and b) a second therapy or agent. In some embodiments, the second therapy or agent is an anti-RANKL antibody. In some embodiments, the second agent or therapy comprises an agent selected from the group consisting of parathyroid hormone (PTH), selective Estrogen Receptor Modulator (SERM), bisphosphonates, prostaglandin E (PGE) receptor agonists, VEGF, and tgfβ, growth factors (myostatin), and calcitonin.

In some embodiments, methods of treating a disease or condition (e.g., a bone-related disease) in an individual are provided, comprising administering to the individual a) an effective amount of a bispecific construct (e.g., any of the bispecific constructs described herein); and b) an anti-RANKL antibody. In some embodiments, the bispecific construct comprises an antibody portion comprising a heavy chain variable region (V _H) and a light chain variable region (V _L), wherein V _H comprises i) a polypeptide comprising SEQ ID NO:1, ii) an HC-CDR1 comprising the amino acid sequence of SEQ ID NO:2, and iii) an HC-CDR2 comprising the amino acid sequence of SEQ ID NO:3, or a variant thereof comprising up to 5, 4, 3, 2 or 1 amino acid substitutions in the HC-CDR, and V _L comprises i) an amino acid sequence comprising SEQ ID NO:4 or 26, ii) an LC-CDR1 comprising the amino acid sequence of SEQ ID NO:5, and iii) an LC-CDR2 comprising the amino acid sequence of SEQ ID NO:6, or a variant thereof comprising up to 5, 4, 3, 2 or 1 amino acid substitutions in the LC-CDR. In some embodiments, the anti-RANKL antibody comprises a second heavy chain variable region (V _H-2) and a second light chain variable region (V _L-2), wherein V _H-2 comprises a polypeptide comprising SEQ ID NO:7, comprising the amino acid sequence of SEQ ID NO:8 and an HC-CDR2 comprising the amino acid sequence of SEQ ID NO:9, and V _L-2 comprises an HC-CDR3 comprising the amino acid sequence of SEQ ID NO:10, comprising the amino acid sequence of SEQ ID NO:11, comprising the amino acid sequence of SEQ ID NO:12, and LC-CDR3 of the amino acid sequence of seq id no.

In some embodiments, the bispecific construct and the second agent or therapy are administered simultaneously. In some embodiments, the bispecific construct and the second agent or therapy are administered simultaneously. In some embodiments, the bispecific construct and the second agent or therapy are administered sequentially.

V. intravenous compositions, kits and articles of manufacture

Also provided herein are compositions (e.g., formulations, e.g., pharmaceutical compositions) comprising any of the bispecific constructs or anti-sclerostin antibody portions described herein, nucleic acids encoding the antibody portions, vectors (vectors) comprising nucleic acids encoding the antibody portions, or host cells comprising the nucleic acids or vectors (vectors).

In some embodiments, pharmaceutical compositions are provided that include a bispecific construct (e.g., any of the bispecific constructs described herein) and a pharmaceutically acceptable carrier (carrier). In some embodiments, the composition further comprises an agent selected from the group consisting of parathyroid hormone (PTH), selective Estrogen Receptor Modulator (SERM), VEGF, tgfβ, growth factor (myostatin), and calcitonin.

Suitable formulations of the bispecific constructs described herein may be obtained by mixing the bispecific construct or anti-sclerostin antibody moiety of the desired purity with an optional pharmaceutically acceptable carrier, excipient or stabilizer (Remington' sPharmaceutical Sciences, 16 th edition, osol, code a (1980)) in the form of a lyophilized formulation or aqueous solution. Acceptable carriers, excipients, or stabilizers are nontoxic to recipients at the dosages and concentrations employed, and include buffers such as phosphate, citrate, and other organic acids; antioxidants including ascorbic acid and methionine; preservatives (e.g., octadecyl dimethylbenzyl ammonium chloride, hexamethyl diammonium chloride, benzalkonium chloride, benzethonium chloride, phenolic alcohols, butanols or benzyl alcohols, alkyl p-hydroxybenzoates, such as methyl or propyl p-hydroxybenzoate, catechol, resorcinol, cyclohexanol, 3-pentanol, and m-cresol); a low molecular weight (less than about 10 residues) polypeptide; proteins, such as serum albumin, gelatin or immunoglobulins; hydrophilic polymers such as polyvinylpyrrolidone; amino acids such as glycine, glutamine, asparagine, histidine, arginine or lysine; monosaccharides, disaccharides, and other carbohydrates including glucose, mannose, or dextrins; chelating agents such as EDTA; sugars such as sucrose, mannitol, trehalose or sorbitol; salt-forming counterions such as sodium; metal complexes (e.g., zn-protein complexes); and/or nonionic surfactants such as TWEEN ^TM、PLURONICS^TM or polyethylene glycol (PEG). Lyophilized formulations suitable for subcutaneous administration are described in WO 97/04801. Such lyophilized formulations can be reconstituted with a suitable diluent to high protein concentrations and the reconstituted formulation can be administered subcutaneously to the individual to be imaged, diagnosed or treated herein.

Formulations for in vivo administration must be sterile. This can be easily achieved by filtration, for example, through sterile filtration membranes.

Kits comprising any of the bispecific constructs or anti-sclerostin antibody moieties described herein are also provided. The kit can be used in any of the methods described herein for modulating cellular composition or treatment.

In some embodiments, kits are provided that include a bispecific construct that specifically binds to sclerostin.

In some embodiments, the kit further comprises a device capable of delivering the bispecific construct to an individual. One type of device for applications such as parenteral delivery is a syringe for injecting a composition into a subject. Inhalation devices may also be used for certain applications.

In some embodiments, the kit further comprises a therapeutic agent for treating a disease or condition, such as a bone-related disease, e.g., osteogenesis imperfecta, bone sclerosis, or a disease or condition associated with bone loss.

The kits of the application are in a suitable package. Suitable packages include, but are not limited to, vials, bottles, cans, flexible packages (e.g., sealed mylar or plastic bags), and the like. The kit may optionally provide additional components, such as buffers and interpretation information.

Accordingly, the present application also provides an article. The article may comprise a container and a label or package insert on or associated with the container. Suitable containers include vials (e.g., sealed vials), bottles, cans, flexible packages, and the like. Typically, the container contains the composition and may have a sterile access port (e.g., the container may be an intravenous solution bag or a vial having a stopper pierceable by a hypodermic injection needle). The label or package insert composition is used for imaging, diagnosis or treatment of a particular condition in an individual. The label or package insert will further include instructions for applying the composition to an individual and imaging the individual. The tag may indicate an indication of reconstruction and/or use. The container containing the composition may be a multi-use vial that allows for repeated administration (e.g., 2-6 administrations) of the reconstituted formulation. Package insert refers to instructions typically included in commercial packages of diagnostic products that include information regarding indications, usage, dosage, administration, contraindications, and/or warnings regarding the use of such diagnostic products. In addition, the article of manufacture may further comprise a second container comprising a pharmaceutically acceptable buffer, such as bacteriostatic water for injection (BWFI), phosphate buffered saline, ringer's solution, and dextrose solution. It may also include other materials, including other buffers, diluents, filters, needles and syringes, as desired from a commercial and user standpoint.

The kit or article of manufacture may comprise a plurality of unit doses of the composition and instructions for use, packaged in amounts sufficient for storage and use in pharmacies such as hospital pharmacies and dispensing pharmacies.

Those skilled in the art will recognize that several embodiments are possible within the scope and spirit of the invention. The invention will now be described in more detail with reference to the following non-limiting examples. The following examples further illustrate the invention but, of course, should not be construed as in any way limiting its scope.

Examples

The following examples are merely illustrative of the application and should not be construed as limiting the application in any way. The following examples and detailed description are provided for purposes of illustration and not limitation.

Example 1 production of bispecific antibodies

Bispecific antibodies targeting sclerostin and RANKL were generated. See tables 9 and 10 for sequences of exemplary antibodies targeting sclerostin and RANKL.

TABLE 9 CDR sequences of exemplary anti-sclerostin antibodies

TABLE 10 CDR sequences of exemplary anti-RANKL antibodies

Specifically, the following sclerostin/RANKL pairings were generated: hAb-1 Xdenomab and hAb-2 Xdenomab.

In one embodiment (see FIG. 2 (A)), the two heavy chains of the anti-sclerostin antibody are converted to a 'Knob-into-Hole' asymmetric IgG structure. One anti-RANKL denomab Fv domain was converted to scFv with two different orientations of VH and VL linked by a (GGGGS) 4 linker. Mutations such as G100C in VH and G44C in VL contribute to correct assembly of scFv. An anti-RANKL SCFV is linked to one of the C-termini of the two IgG heavy chains of the anti-sclerostin humanized antibody by a GGGGSGGGGSGGGGS (SEQ ID NO: 17) linker, resulting in a 2:1 IgG-scFv bispecific.

In another embodiment (see fig. 2 (B)), the anti-sclerostin antibody and the anti-rankldenomab are converted to a 'Knob-into-Hole' bispecific antibody with an asymmetric IgG structure. The CL domain of anti-RANKL denomab includes mutations of S176C and C214S, and the CH1 domain includes mutations such as F170C and C131S to form orthogonal CH ₁ -CK disulfide bonds, thereby enabling proper pairing of the light chains. The second anti-sclerostin antibody Fab fragment was linked to the C-terminus of the first anti-sclerostin heavy chain by a GGGGSGGGGSGGGGS (SEQ ID NO: 17) linker, resulting in a 2:1 bispecific IgG-Fab.

In another embodiment (see FIG. 2 (C)), the two heavy chains of the anti-sclerostin antibody are converted to a 'Knob-into-Hole' asymmetric IgG structure. One anti-sclerostin Fv domain was converted to an scFv with two different orientations of VH and VL linked by a (GGGGS) 4 linker. One anti-RANKL denomab Fv domain was converted to scFv with two different orientations of VH and VL linked by a (GGGGS) 4 linker. Mutations such as G100C in VH and G44C in VL facilitate proper assembly of anti-RANKL or anti-sclerostin scFv. The anti-sclerostin scFv and anti-RANKL SCFV were linked to the C-terminus of the two IgG heavy chains of the anti-sclerostin antibody via a GGGGSGGGGSGGGGS (SEQ ID NO: 17) linker, respectively, to form a 3:1 bispecific of the IgG-scFv.

Table 3 below sets forth the structural forms and sequences of various anti-sclerostin bispecific antibodies.

TABLE 3 anti-sclerostin X anti-RANKL bispecific antibodies

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Bispecific molecules were transiently expressed in adherent 293 6e cells in 96-well plates. 24 hours prior to transfection, adherent 293 6E cells were seeded at 5E4 cells per well in 25 μg/ml serum-free KOP293 medium (Margarland kai R Biotechnology Co., ltd., cat No. K03252) and 5% FBS in poly-D-lysine coated 96 well tissue culture plates and incubated overnight in 5% CO ₂ at 37 ℃. On the day of transfection, 100ng (40 ng/. Mu.l) of each of the corresponding heavy and light chain DNA of the binding molecule was mixed together. To the DNA mixture was added 25. Mu.l/well of serum-free medium KOP293. After incubation for 15-30 minutes at room temperature, the transfection mixture was added to the plates, which were inoculated on the previous day and mixed with gentle shaking. The plates were placed back into 37℃and 5% CO ₂ incubator overnight. The next day, the medium and transfection mixture was aspirated and replaced with 130 μl of serum-free medium including 0.5% tryptone. Plates were incubated for an additional 6 days. Conditioned Medium (CM) was harvested on day 7 post-transfection. The plate was spun at 1000rpm for 5 minutes to pellet any cell debris. The supernatant was carefully transferred to a sterile polypropylene block.

The antibodies were purified by protein a affinity chromatography and buffer exchanged in PBS (pH 7.2). The concentration of purified antibody was determined by reading the absorbance at 280nm, using the theoretical determination extinction coefficient of the protein.

Example 2 binding kinetics and affinity of anti-sclerostin x anti-RANKL bispecific antibodies

The binding kinetics and affinity of anti-sclerostin x anti-RANKL bispecific antibodies were determined using Gator (Probe Life) biological layer interferometry (bio-layer interferometry, BLI). Antibodies were immobilized on anti-hFc biosensors using a 5 μg/ml solution. A2-fold serial dilution of sclerostin (1. Mu.g/ml) and RANKL (4. Mu.g/ml) in kinetic buffer (PBS, pH 7.4,0.05% Tween-20, 0.2% BSA) was used as analyte. Affinity (K _D) and kinetic parameters (K _on and K _off) were calculated from a global fit (1:1) of the data using Gator software. The results are summarized in table 4.

TABLE 4 summary of binding kinetics of bispecific antibodies to human sclerostin and RANKL

A detection limit, indicating that the off rate is very slow and exceeds the quantization limit of Gator

B affinity K _D value was calculated by K _off/K_on, and in the case of K _off being LOD, the K _D value was estimated to be about 10pM, which is the detection limit of Gator

EXAMPLE 3 in vitro sclerostin-and RANKL-neutralizing Activity

Exemplary bispecific antibodies were able to neutralize sclerostin and block Wnt 1-induced TCF/LEF luciferase activity as determined in HEK 293-based assays. Addition of sclerostin antagonizes Wnt1 signaling, resulting in reduced luciferase activity. In contrast, the addition of sclerostin antibodies will block the reduced signal and restore luciferase activity. The HEK293/TCF/LEF/Wnt1 cell line was obtained from Askgene (Askgene, calif.). After production, the cells were cultured in RPMI1640 medium comprising L-glutamine (Life Technologies, CA) comprising 10% Fetal Bovine Serum (FBS), non-essential amino acids, sodium pyruvate, 2-mercaptoethanol, 1% penicillin/streptomycin, 400 μg/ml G418 and 2 μg/ml puromycin. Cells were harvested and plated into white 96-well plates at a concentration of 30,000 cells/well. When the inhibitory effect of the antagonists was tested, the medium was removed and 50 μl of assay medium (medium without G418 and puromycin) comprising 10mM LiCl was added to each well. When testing the neutralizing activity of the antibodies, serial dilutions of the exemplary antibodies were performed in assay medium. A fixed amount of sclerostin was added and incubated for 15 minutes with final concentration of 1 μg/ml in each well and titers of bispecific antibodies of 400, 200, 100, 50, 25, 12.5 and 6.25nM. Then, 50. Mu.l of the medium was transferred to the assay plate, incubated at 37℃and 5% CO ₂ for 6 hours, 100. Mu.l/well bioluminescence reaction was added and Relative Luminescence Units (RLU) were recorded using a BioTek Gen5 luminometer. EC ₅₀ was calculated by fitting a four parameter dose-response curve from three replicates.

Exemplary bispecific antibodies are capable of neutralizing RANKL in the RAW264.7 cell line of a luciferase reporter stably expressed under the control of a nuclear factor- κb (NF- κb) responsive element. RAW264.7 cells were purchased from ATCC, transfected with pCM1.1 vector (vector) (Luc/NF-. Kappa.B/Hygro), and 150mg/ml hygromycin B was selected 24 hours after transfection. The parental RAW264.7 cells were maintained in DMEM comprising 10% fbs, 1% p/S, 1% glutamine, while the transgenic NF- κb-Luci RAW264.7 cells were cultured in DMEM comprising 10% fbs, 1% p/S, 1% glutamine, and 150mg/ml hygromycin B. During bioassay, DMEM medium including 10% fbs was used as the assay medium. The hygromycin resistance stable pool was then subcloned by limiting dilution and the various single cell derived variants were further screened by addition of RANKL and measurement of luciferase expression to select the best responsive variants (NF- κb-Luci RAW264.7 cells).

NF- _κ B-Luci RAW264.7 cells were seeded at a density of 8X 10 ⁴ cells in 50ml assay medium per well. Exemplary bispecific antibodies were serially diluted to 8 concentrations using assay medium mixed with 0.6 μg/ml human recombinant RANKL, starting at 900nM. 8 serially diluted samples were added in a volume of 50ml per well and incubated at 37℃and 5% CO ₂ for 24h. After adding 100 μl of Bio-Lite fluorescent reagent per well, relative Luciferase Units (RLU) were recorded using a BioTek Gen5 luminometer. EC ₅₀ was calculated by fitting a four parameter dose-response curve from three replicates.

All bispecific antibodies were able to fully neutralize Wnt-antagonism from sclerostin and NF- κb activation from RANKL in a dose-dependent manner. EC ₅₀ activity is shown in table 5.

TABLE 5 hard bone statin neutralizing Activity in HEK293/TCF/LEF/Wnt1 reporter assay and RANKL neutralizing Activity of bispecific antibodies in RAW264.7/NF-kB/Luc-Hygro reporter assay

EXAMPLE 4 pharmacodynamic studies of bispecific antibodies

The N-terminal pro peptide of type I procollagen (P1 NP) and the C-terminal of the bone resorption biomarker of type I collagen telopeptide (CTX-1) are two widely accepted indicators of specific bone homeostasis. To test the pharmacodynamic effects of bispecific antibodies, normal male cynomolgus monkeys were subcutaneously injected with the different bispecific antibodies described above. Blood samples were obtained on day 3 post injection. The serum sample is then separated by centrifugation. Serum P1NP and CTX-1 levels were measured using the P1NP test kit and serum collagen cross-linking ELISA kit (Serum CrossLaps ELISAkit) according to the manufacturer's instructions, respectively. The results show that administration of bispecific antibodies only caused a significant increase in serum P1NP levels at 3 days post injection. Serum P1NP levels for the different bispecific antibodies increased between 43.18±4.3% and 86.61 ±26.2% on day 3 when compared to the pre-dosing baseline (table 6). Furthermore, on day 3, serum CTX-1 levels of different bispecific antibodies were reduced by 63.07 ±5.8% to-96.31±1.6% compared to baseline in response to bispecific antibody injections (table 6). The results indicate that bispecific antibodies can both strongly increase bone formation and decrease bone resorption, suggesting their profound efficacy in the treatment of diseases or conditions associated with low or poor bone mass such as reduced bone mass or osteoporosis, osteogenesis imperfecta, multiple myeloma bone disease and solid tumor bone metastasis in men and women. Anti-sclerostin (e.g., hAb-2) or anti-RANKL (e.g., denomab) mabs have difficulty in causing a significant increase in P1NP and a decrease in CTX-1 at the same time. The present invention found that the structure and sequence design of bispecific antibodies had a significant effect on both bone marker serum concentrations at the same time, with the structure and sequence of 2:1igg-Fab (BAP 0079) bispecific antibodies achieving unexpected technical effects of optimal increase of P1NP and decrease of CTX-1, even at much lower doses, compared to other bispecific antibodies. The data are shown in table 6.

Table 6 serum concentrations of P1NP and CTX-1 in cynomolgus monkeys 3 days after injection.

Example 5 bispecific antibodies show therapeutic efficacy in a multiple myeloma bone disease mouse model.

Bispecific antibodies were also evaluated in the mm.1s mouse human Multiple Myeloma Bone Disease (MMBD) model. To build animal models, immunocompromised mice (NCG) were used in the study. Male NCG mice 6 weeks old were purchased and raised under SPF conditions. 250 ten thousand tail veins were inoculated into NCG mice using MM tumor cells MM.1S-Luc. After one week, mice were subjected to live imaging to visualize tumor cells migrating into bone marrow. Antibodies were then given subcutaneously twice weekly at 50mg/kg for 4 weeks. Bone samples were collected 4 weeks after treatment for μct analysis of bone mass, strength and structural changes in vertebrae and femur. In vivo tumor burden is acquired at the end of treatment using a living bioluminescence imaging system. All data are expressed as mean ± Standard Error of Mean (SEM) and analyzed by one-way analysis of variance (ANOVA) with the control group using uncorrected Fisher's LSD test.

Tail vein injection of mm.1s cells showed accumulation of larger amounts of tumor cells in bone marrow, indicating establishment of MMBD. The μct analysis showed that tumor cells caused a number of bone lesions, particularly proximal and distal cancellous bone of the femur. Bispecific antibodies treated for 4 weeks caused a significant reduction in bone damage. In addition, it results in a significant increase in cancellous and cortical bone of the distal femur. The relative trabecular bone volume (BV/TV) of the bispecific antibody treated group and the control group was 73.17 ±3.11% and 29.31±2.86% (p < 0.0001), and the cortical BV/TV of the bispecific antibody treated group and the control group was 34.12±1.06% and 22.27±1.16% (p < 0.0001). The density of cancellous Bone Marrow (BMD) was 0.50.+ -. 0.02 and 0.17.+ -. 0.03 (p < 0.0001) for the bispecific antibody treated group and the control group, respectively, and 0.22.+ -. 0.01 and 0.14.+ -. 0.01 (p < 0.0001) for the bispecific antibody treated group and the control group, respectively. These results demonstrate the profound efficacy of bispecific antibody treatment for treating diseases or conditions associated with low or poor bone mass (e.g., bone metastasis of malignant tumors and/or solid tumor bone metastasis). Meanwhile, compared with the control group, the tumor burden in the bioluminescence imaging of animals in the treatment group is significantly reduced (total flux is 1.24×10 ¹⁰ p/s and 1.77×10 ¹⁰ p/s, p < 0.05), which indicates that the bispecific antibody can inhibit tumor growth and migration.

Example 6. Accelerated degradation analysis.

Exemplary bispecific antibodies were dissolved at 10mg/ml in buffer solution, then placed in a 40 ℃ constant temperature and humidity chamber protected from light, and incubated for 0, 7 and 14 days, before sampling for examination. The samples were analyzed for percent high molecular weight (% HMW) soluble aggregates using SEC. HMW soluble aggregate formation by SEC test increased by less than 10%. These results demonstrate that exemplary bispecific antibodies of the invention are stable at a concentration of 10nM for at least 14 days at elevated temperatures of 40 ℃.

EXAMPLE 7 repeated freeze/thaw analysis

Repeated freeze/thaw analysis of exemplary bispecific antibodies was assessed using protein concentrated at 10mg/ml in a buffer formulation. Four freeze/thaw cycles (a single cycle including incubation at-80 ℃ for 24 hours followed by thawing at 25 ℃ followed by gentle mixing) were performed and the percent of high molecular weight (% HMW) soluble aggregates were evaluated using SEC. The increase in HMW soluble aggregate formation was less than 10%. These results demonstrate that exemplary bispecific antibodies of the invention are stable at 10nM concentrations after multiple freeze/thaw cycles.

EXAMPLE 8 Oxidation resistance analysis

The oxidation resistance of the exemplary bispecific antibodies was evaluated with protein concentrated at 10mg/ml in a buffered formulation, with 0.1% t-butyl hydroperoxide (tBHP) added as an oxidizing agent. The exemplified proteins were placed in a constant temperature and humidity chamber protected from light at 25 ℃ and incubated for 7 days, then sampled for examination of the percentage of high molecular weight (% HMW) soluble aggregates using SEC. The increase in HMW soluble aggregate formation was less than 10%. These results indicate that exemplary bispecific antibodies of the invention are stable in an oxidizing environment at a concentration of 10nM.

Sequence listing

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Claims

1. A bispecific construct comprising a first antibody moiety that specifically recognizes sclerostin and a second antibody moiety that specifically recognizes RANKL, wherein the molar ratio of the first antibody moiety to the second antibody moiety is higher than 1:1, wherein the first antibody moiety binds to an epitope on sclerostin, wherein the epitope comprises the amino acid sequence of SEQ ID NO:35, and an amino acid sequence shown in seq id no.

2. The bispecific construct of claim 1, wherein the molar ratio of the first antibody moiety to the second antibody moiety is from 2:1 to 5:1; preferably 2:1 or 3:1.

3. The bispecific construct of claim 1 or claim 2, wherein the first antibody portion comprises a heavy chain variable region (V _H) and a light chain variable region (V _L) and the second antibody portion comprises a second heavy chain variable region (V _H-2) and a second light chain variable region (V _L-2).

4. The bispecific construct of claim 3, wherein the construct comprises:

a) A first polypeptide comprising a common light chain comprising, from N-terminus to C-terminus, i) a light chain variable region (V _L), ii) a light chain constant domain;

b) A second polypeptide comprising a first heavy chain comprising, from N-terminus to C-terminus, i) a heavy chain variable region (V _H), ii) a heavy chain constant domain, and iii) a first Fc domain; or i) a heavy chain variable region (V _H), ii) a heavy chain constant domain, iii) a first Fc domain; and iv) a scFv fragment comprising said V _H and said V _L,

C) A third polypeptide comprising a second heavy chain comprising, from N-terminus to C-terminus, i) a heavy chain variable region (V _H), ii) a heavy chain constant domain, iii) a second Fc domain; and iv) scFv fragments comprising said V _H-2 and V _L-2,

Wherein the first and second Fc domains form an Fc fragment.

5. The bispecific construct of claim 3, wherein the construct comprises:

a) First and second polypeptides comprising a common light chain comprising, from N-terminus to C-terminus, i) a light chain variable region (V _L), ii) a light chain constant domain;

b) A third polypeptide comprising a first heavy chain comprising, from N-terminus to C-terminus, i) a heavy chain variable region (V _H), ii) a heavy chain constant domain, iii) a first Fc domain, iv) a heavy chain variable region (V _H), and V) a heavy chain constant domain; or i) a heavy chain variable region (V _H), ii) a heavy chain constant domain, iii) a heavy chain variable region (V _H), iv) a heavy chain constant domain, V) a first Fc domain;

c) A fourth polypeptide comprising a second heavy chain comprising, from N-terminus to C-terminus, i) the V _H-2, ii) a heavy chain constant domain, and iii) a second Fc domain; or i) the V _H-2, ii) a heavy chain constant domain, and iii) a second Fc domain, iv) a heavy chain variable region (V _H), and V) a heavy chain constant domain;

d) A fifth polypeptide comprising a second light chain comprising, from N-terminus to C-terminus, i) the V _L-2, ii) a light chain constant domain;

wherein the first and second Fc domains form an Fc fragment.

6. The bispecific construct of claim 4 or claim 5, wherein one of the first and the second Fc domain comprises a T366W mutation, and optionally an S354C mutation, and wherein the other Fc domain comprises a T366S mutation, an L368A mutation, a Y407V mutation, and optionally a Y349C mutation, wherein numbering is according to the EU index.

7. The bispecific construct of any one of claims 1 to 6, the first antibody portion comprising a heavy chain variable region (V _H) and a light chain variable region (V _L), wherein:

The V _H comprises a polypeptide comprising SEQ ID NO:1 comprising the amino acid sequence of SEQ ID NO:2 and an HC-CDR2 comprising the amino acid sequence of SEQ ID NO:3, or a variant thereof comprising up to 5, 4, 3, 2, or 1 amino acid substitutions in the HC-CDR; and

The V _L comprises a polypeptide comprising SEQ ID NO:4 or 26, comprising the amino acid sequence of SEQ ID NO:5, and an LC-CDR2 comprising the amino acid sequence of SEQ ID NO:6, or a variant thereof comprising up to 5, 4, 3, 2 or 1 amino acid substitutions in said LC-CDR.

8. The bispecific construct of any one of claims 1 to 7, wherein the first antibody portion comprises a heavy chain variable region (V _H) and a light chain variable region (V _L), wherein:

a) The V _H comprises a polypeptide comprising SEQ ID NO:1, comprising the amino acid sequence of SEQ ID NO:2 and said HC-CDR2 comprising the amino acid sequence of SEQ ID NO:3, said HC-CDR3 of the amino acid sequence of 3; and V _L comprises a polypeptide comprising SEQ ID NO:4, comprising the amino acid sequence of SEQ ID NO:5 and said LC-CDR2 comprising the amino acid sequence of SEQ ID NO:6, or

B) The V _H comprises a polypeptide comprising SEQ ID NO:1, comprising the amino acid sequence of SEQ ID NO:2 and said HC-CDR2 comprising the amino acid sequence of SEQ ID NO:3, said HC-CDR3 of the amino acid sequence of 3; and V _L comprises a polypeptide comprising SEQ ID NO:26, comprising the amino acid sequence of SEQ ID NO:5 and said LC-CDR2 comprising the amino acid sequence of SEQ ID NO:6 amino acid sequence of said LC-CDR3.

9. The bispecific construct of any one of claims 1 to 8, wherein the first antibody portion comprises a heavy chain variable region (V _H) and a light chain variable region (V _L), wherein:

a) HC-CDR1, HC-CDR2 and HC-CDR3, comprising a polypeptide having the amino acid sequence of SEQ ID NO:27, and LC-CDR1, LC-CDR2, and LC-CDR3, respectively, comprising the amino acid sequences of CDR1, CDR2, and CDR3 within said V _H of the sequence shown in SEQ ID NO:28, CDR1, CDR2, and CDR3 amino acid sequences within said V _L of the sequence shown; or (b)

B) HC-CDR1, HC-CDR2 and HC-CDR3, comprising a polypeptide having the amino acid sequence of SEQ ID NO:27, and LC-CDR1, LC-CDR2, and LC-CDR3, respectively, comprising the amino acid sequences of CDR1, CDR2, and CDR3 within said V _H of the sequence shown in SEQ ID NO:29, CDR1, CDR2, and CDR3 amino acid sequences within said V _L of the sequence shown.

10. The bispecific construct of any one of claims 1 to 9, wherein the first antibody portion comprises a heavy chain variable region (V _H) and a light chain variable region (V _L), wherein the V _H comprises the amino acid sequence of SEQ ID NO:27, or a variant comprising an amino acid sequence having at least about 80% sequence identity; and/or wherein said V _L comprises SEQ ID NO:28 or 29 or a variant comprising an amino acid sequence having at least about 80% sequence identity.

11. The bispecific construct of claim 10, wherein:

a) The V _H comprises SEQ ID NO:27, or a variant comprising an amino acid sequence having at least about 80% sequence identity; and V _L comprises SEQ ID NO:28, or a variant comprising an amino acid sequence having at least about 80% sequence identity; or (b)

B) The V _H comprises SEQ ID NO:27, or a variant comprising an amino acid sequence having at least about 80% sequence identity; and V _L comprises SEQ ID NO:29, or a variant comprising an amino acid sequence having at least about 80% sequence identity.

12. The bispecific construct according to any one of claims 1 to 11, wherein the RANKL is human RANKL.

13. The bispecific construct of any one of claims 3 to 12, wherein the V _H-2 comprises a polypeptide comprising SEQ ID NO:7, comprising the amino acid sequence of SEQ ID NO:8 and said HC-CDR2 comprising the amino acid sequence of SEQ ID NO:9 and the V _L-2 comprises an amino acid sequence comprising SEQ ID NO:10, comprising the amino acid sequence of SEQ ID NO:11 and said LC-CDR2 comprising the amino acid sequence of SEQ ID NO:12, and said LC-CDR3 of the amino acid sequence of seq id no.

14. The bispecific construct of claim 13, wherein the V _H-2 comprises SEQ ID NO:13, or a variant comprising an amino acid sequence having at least about 80% sequence identity; and V _L-2 comprises SEQ ID NO:14, or a variant comprising an amino acid sequence having at least about 80% sequence identity.

15. The bispecific construct of any one of claims 1 to 14, wherein the construct comprises:

a) A first polypeptide comprising a common light chain comprising, from N-terminus to C-terminus, i) the V _L, ii) a light chain constant domain;

b) A second polypeptide comprising a first heavy chain comprising, from N-terminus to C-terminus, i) the V _H, ii) a heavy chain constant domain, and iii) a first Fc domain; or i) a heavy chain variable region (V _H), ii) a heavy chain constant domain, iii) a first Fc domain; iv) an scFv fragment comprising V _H and V _L according to any one of claims 7 to 11;

c) A third polypeptide comprising a second heavy chain comprising, from N-terminus to C-terminus, i) the V _H, ii) a heavy chain constant domain, iii) a second Fc domain; and iv) a scFv fragment comprising V _H-2 according to claim 13 or claim 14 and V _L-2 according to claim 13 or claim 14,

Wherein the first and second Fc domains form an Fc fragment.

16. The bispecific construct of any one of claims 4 and 6 to 15, comprising:

1) The first polypeptide comprises SEQ ID NO:30, said second polypeptide comprises the amino acid sequence of SEQ ID NO:33, and the third polypeptide comprises the amino acid sequence of SEQ ID NO:34, an amino acid sequence of seq id no;

2) The first polypeptide comprises SEQ ID NO:30, said second polypeptide comprises the amino acid sequence of SEQ ID NO:36, and the third polypeptide comprises the amino acid sequence of SEQ ID NO:37, an amino acid sequence of seq id no;

3) The first polypeptide comprises SEQ ID NO:30, said second polypeptide comprises the amino acid sequence of SEQ ID NO:42, and the third polypeptide comprises the amino acid sequence of SEQ ID NO:43, an amino acid sequence of seq id no; or (b)

4) The first polypeptide comprises SEQ ID NO:30, said second polypeptide comprises the amino acid sequence of SEQ ID NO:46, and the third polypeptide comprises the amino acid sequence of SEQ ID NO: 47.

17. The bispecific construct of any one of claims 1 to 14, wherein the construct comprises:

a) First and second polypeptides comprising a common light chain comprising, from N-terminus to C-terminus, i) the V _L, ii) a light chain constant domain;

b) A third polypeptide comprising a first heavy chain comprising, from N-terminus to C-terminus, i) the V _H, ii) a heavy chain constant domain, iii) a first Fc domain, iv) the V _H, and V) a heavy chain constant domain; or i) the V _H, ii) a heavy chain constant domain, iii) the V _H, iv) a heavy chain constant domain, V) a first Fc domain;

c) A fourth polypeptide comprising a second heavy chain comprising, from N-terminus to C-terminus, i) V _H-2 according to claim 13 or claim 14, ii) a heavy chain constant domain, and iii) a second Fc domain; or i) V _H-2 according to claim 13 or claim 14, ii) a heavy chain constant domain, and iii) a second Fc domain, iv) the V _H, and V) a heavy chain constant domain;

d) A fifth polypeptide comprising a second light chain comprising, from N-terminus to C-terminus, i) a V _L-2 according to claim 13 or claim 14, ii) a light chain constant domain;

wherein the first and second Fc domains form an Fc fragment.

18. The bispecific construct of any one of claims 5 to 14 and 17, comprising:

1) The first and second polypeptides comprise SEQ ID NOs: 31, said third polypeptide comprising the amino acid sequence of SEQ ID NO:38, said fourth polypeptide comprising the amino acid sequence of SEQ ID NO:39, and the fifth polypeptide comprises the amino acid sequence of SEQ ID NO:32, an amino acid sequence of seq id no;

2) The first and second polypeptides comprise SEQ ID NOs: 31, said third polypeptide comprising the amino acid sequence of SEQ ID NO:38, said fourth polypeptide comprising the amino acid sequence of SEQ ID NO:41, said fifth polypeptide comprising the amino acid sequence of SEQ ID NO:32, an amino acid sequence of seq id no;

3) The first and second polypeptides comprise SEQ ID NOs: 31, said third polypeptide comprising the amino acid sequence of SEQ ID NO:40, said fourth polypeptide comprising the amino acid sequence of SEQ ID NO:41, said fifth polypeptide comprising the amino acid sequence of SEQ ID NO:32, an amino acid sequence of seq id no; or (b)

4) The first and second polypeptides comprise SEQ ID NOs: 31, said third polypeptide comprising the amino acid sequence of SEQ ID NO:44, said fourth polypeptide comprises the amino acid sequence of SEQ ID NO:45, said fifth polypeptide comprising the amino acid sequence of SEQ ID NO:32, and a sequence of amino acids.

19. The bispecific construct of any one of claims 1 to 18, wherein the antibody moiety is an antibody or antigen-binding fragment thereof selected from the group consisting of a full length antibody, a bispecific antibody, a single chain Fv (scFv) fragment, a Fab 'fragment, a F (ab') ₂, a Fv fragment, a disulfide stabilized Fv fragment (dsFv), a disulfide stabilized scFv (dsscFv), (dsFv) ₂, a Fv-Fc fusion, a scFv-Fv fusion, a diabody, a triabody, and a tetrabody.

20. The bispecific construct of any one of claims 1 to 19, wherein the construct is a full-length antibody comprising an Fc fragment.

21. The bispecific construct of claim 20, wherein the antibody moiety is an scFv fragment.

22. The bispecific construct of any one of claims 1 to 21, wherein the sclerostin is human sclerostin.

23. The bispecific construct of any one of claims 1 to 3 and 5 to 22, wherein the second antibody moiety is a full-length antibody, fab ', (Fab') ₂, fv, single chain Fv (scFv) fragment, scFv-scFv, minibody, diabody, or sdAb.

24. The bispecific construct of claim 23, wherein the second antibody portion is a full length antibody comprising two heavy chains, two light chains, and an Fc fragment, and wherein the first antibody portion is a single chain Fv (scFv) fragment comprising the V _H fused to the V _L.

25. The bispecific construct of claim 24, wherein the first antibody portion is fused to one or both of the heavy chains of the full length antibody.

26. The bispecific construct of any one of claims 23 to 25, wherein the first antibody moiety is fused to one or both of the light chains of the full length antibody.

27. The bispecific construct of claim 25 or 26, wherein the first antibody portion is fused to the N-terminus of one or both of the heavy or light chains of the full length antibody.

28. The bispecific construct of any one of claims 25 to 27, wherein the first antibody moiety is fused to the C-terminus of one or both of the heavy or light chains of the full length antibody.

29. The bispecific construct of any one of claims 25 to 28, wherein the first antibody moiety is fused to the full length antibody by a first linker.

30. The bispecific construct of any one of claims 25 to 28, wherein the first antibody moiety is not fused to the full length antibody by a linker.

31. The bispecific construct of claim 29, wherein the first linker is a sequence selected from SEQ ID NOs: 15 to 25.

32. The bispecific construct of any one of claims 23 to 31, wherein the V _H is fused to the V _L by a second linker.

33. The bispecific construct of claim 32, wherein the scFv fragment comprises the V _H, the second linker, and the V _L from the N-terminus to the C-terminus.

34. The bispecific construct of claim 33, wherein the scFv fragment comprises, from N-terminus to C-terminus, the V _L, the second linker and the V _H, and optionally a C-terminal alanine residue.

35. The bispecific construct of any one of claims 32 to 34, wherein the second linker comprises SEQ ID NO:17 or 18.

36. The bispecific construct of any one of claims 1 to 35, wherein the second antibody moiety is a scFv fragment comprising the V _H-2 and the V _L-2, and wherein the first antibody moiety is a full-length antibody comprising two heavy chains, two light chains, and an Fc fragment.

37. The bispecific construct of claim 36, wherein the second antibody moiety is fused to one or both of the heavy chains of the full length antibody.

38. The bispecific construct of claim 36 or 37, wherein the second antibody portion is fused to one or both of the light chains of the full length antibody.

39. The bispecific construct of claim 37 or 38, wherein the second antibody moiety is fused to the N-terminus of one or both of the heavy or light chains of the full length antibody.

40. The bispecific construct of any one of claims 36 to 39, wherein the second antibody moiety is fused to the C-terminus of one or both of the heavy or light chains of the full length antibody.

41. The bispecific construct of any one of claims 36 to 40, wherein the second antibody moiety is fused to the full length antibody by a first linker.

42. The bispecific construct of any one of claims 36 to 41, wherein the second antibody moiety is not fused to the full length antibody by a linker.

43. The bispecific construct of claim 41, wherein the first linker is a sequence selected from the group consisting of SEQ ID NOs: 15 to 25.

44. The bispecific construct of any one of claims 36 to 43, wherein the V _H-2 is fused to the V _L-2 by a second linker.

45. The bispecific construct of any one of claims 36 to 43, wherein the V _H-2 is not fused to the V _L-2 by a linker.

46. The bispecific construct of claim 44, wherein the scFv fragment comprises the V _H-2, the second linker and the V _L-2 from the N-terminus to the C-terminus.

47. The bispecific construct of claim 44, wherein the scFv fragment comprises the V _L-2, the second linker and the V _H-2, and optionally a C-terminal alanine residue from the N-terminus to the C-terminus.

48. The bispecific construct of any one of claims 44, 46 and 47, wherein the second linker comprises SEQ ID NO:17 or 18.

49. The bispecific construct of any one of claims 1 to 48, wherein the second moiety comprises a half-life extending moiety.

50. The bispecific construct of claim 49, wherein the half-life extending moiety is an Fc fragment.

51. The bispecific construct of any one of claims 2 to 50, wherein the Fc fragment is selected from the group consisting of the Fc fragment of IgG, igA, igD, igE, igM and combinations and hybrids thereof.

52. The bispecific construct of claim 51, wherein the Fc fragment is selected from the group consisting of an Fc fragment of IgG1, igG2, igG3, igG4, and combinations and hybrids thereof.

53. The bispecific construct of claim 51 or claim 52, wherein the Fc fragment comprises an H435R mutation and a Y436F mutation.

54. The bispecific construct of any one of claims 51 to 53, wherein the Fc fragment has reduced effector function compared to a corresponding wild-type Fc fragment.

55. The bispecific construct of any one of claims 52 to 54, wherein the Fc fragment has:

a) Enhanced effector function compared to the corresponding wild-type Fc fragment, and/or

B) An increased FcRn binding affinity compared to the corresponding wild-type Fc fragment.

56. The bispecific construct of any one of claims 1 to 55, wherein the construct is an antibody-drug conjugate or an antibody fusion protein.

57. The bispecific construct of claim 56, wherein the second moiety comprises one or more agents selected from parathyroid hormone (PTH), selective Estrogen Receptor Modulator (SERM), bisphosphonates, prostaglandin E (PGE) receptor agonists, VEGF, tgfβ, growth factors (myostatin), calcitonin, and combinations thereof.

58. A bispecific construct that competitively specifically binds to sclerostin and RANKL with the bispecific construct of any one of claims 1 to 57.

59. A pharmaceutical composition comprising the bispecific construct of any one of claims 1to 58 and a pharmaceutically acceptable carrier (carrier).

60. The pharmaceutical composition of claim 59, wherein the composition further comprises one or more agents selected from the group consisting of parathyroid hormone (PTH), selective Estrogen Receptor Modulator (SERM), VEGF, and tgfβ, growth factors (myostatin), calcitonin, and combinations thereof.

61. An isolated nucleic acid encoding the bispecific construct of any one of claims 1 to 58.

62. A vector comprising the isolated nucleic acid of claim 61.

63. An isolated host cell comprising the isolated nucleic acid of claim 61 or the vector of claim 62.

64. A method of producing an anti-sclerostin construct comprising:

a) Culturing the isolated host cell of claim 63 under conditions effective to express the bispecific construct or a portion thereof; and

B) Obtaining the expressed bispecific construct or part thereof from the host cell.

65. A method of treating and/or preventing a disease or condition in an individual comprising administering to the individual an effective amount of a bispecific construct according to any one of claims 1 to 58, and/or a pharmaceutical composition according to claim 59 or claim 60.

66. The method of claim 65, wherein the disease or condition is a bone-related disorder or cartilage-related disorder, bone marrow or hematological disorder, musculoskeletal rare disease, muscle-related disorder, or cancer.

67. The method of claim 66, wherein the bone-related disorder is osteogenesis imperfecta, osteoporosis or osteopenia (in men and women), osteonecrosis, delayed bone healing, non-union fractures, multiple myeloma-related bone disorders, primary bone tumors, bone metastases of malignant tumors, solid tumor bone metastases, inflammatory or infectious bone diseases, osteomalacia, hypercalcemia, paget's disease, inactivity-induced bone loss, glucocorticoid-induced bone loss, inflammation-induced bone loss including arthritis-induced bone loss, aerospace osteoporosis/osteopenia due to reduced weight or other diseases or conditions associated with: a) Bone loss in quantity or mass or both and/or b) abnormalities in bone structure and mass.

68. The method of claim 67, wherein said bone-related disorder is osteoporosis or osteopenia.

69. The method of claim 67, wherein said bone-related disorder is osteogenesis imperfecta.

70. The method of claim 67, wherein said bone-related disorder is multiple myeloma and multiple myeloma-related bone disorders.

71. The method of claim 66, wherein the cartilage disorder is chondromatosis, cartilage dysplasia, chondral dysplasia, myotonic cartilage, near cortical chondrioma, knee cartilage tear, bone fibrodysplasia, osteoarthritis, osteogenesis imperfecta, hypophosphatemic rickets, or osteochondral dystrophy.

72. The method of claim 66, wherein the muscle-related disorder is sarcopenia and cancer sarcopenia.

73. A method of promoting healing after a bone or joint surgery in an individual comprising administering to the individual an effective amount of an anti-sclerostin construct according to any one of claims 1 to 58 and/or a pharmaceutical composition according to claim 59 or claim 60.

74. The method of any one of claims 65 to 73, wherein the bispecific construct is administered to the individual by subcutaneous injection, intravenous injection, intramuscular injection, or oral or parenteral administration.

75. The method of any one of claims 65 to 74, wherein the method further comprises administering a second agent or therapy.

76. The method of claim 75, wherein the second agent or therapy comprises an anti-RANKL antibody.

77. The method of claim 75, wherein the second agent or therapy comprises an agent selected from the group consisting of parathyroid hormone (PTH), selective Estrogen Receptor Modulator (SERM), bisphosphonates, prostaglandin E (PGE) receptor agonists, VEGF, tgfβ, growth factors (myostatin), and calcitonin.

78. The method of any one of claims 65-77, wherein the individual is a human.