Antibodies Reactive with B7-H3, Immunologically Active Fragments Thereof and Uses Thereof

Abstract

The present invention relates to antibodies and their fragments that are immunoreactive to the mammalian, and more particularly, the human B7-H3 receptor and to uses thereof, particularly in the treatment of cancer and inflammation. The invention thus particularly concerns humanized B7-H3-reactive antibodies and their immunoreactive fragments that are capable of mediating, and more preferably enhancing the activation of the immune system against cancer cells that are associated with a variety of human cancers.

1 - 20 . (canceled) 
     
     
         21 . A method of treating cancer in a human, comprising administering one or more dose(s) of an isolated antibody or an immunoreactive fragment thereof, wherein said antibody or said fragment thereof comprises a variable domain that specifically binds an extracellular domain of B7-H3 and comprises:
 (A) the amino acid sequences of SEQ ID NOs: 5, 7 and 9; or   (B) the amino acid sequences of SEQ ID NOs: 13, 15 and 17.   
     
     
         22 . The method of  claim 21 , wherein said antibody is a humanized monoclonal antibody. 
     
     
         23 . The method of  claim 22 , wherein said antibody comprises a variant human IgG1 Fc region, wherein said variant human IgG1 Fc region comprises at least one amino acid modification(s) relative to a wild-type Fc region, said amino acid modification(s) altering the affinity or avidity of said variant Fc region for binding to an FcγR such that said antibody exhibits enhanced effector function relative to said wild-type Fc region. 
     
     
         24 . The method of  claim 23 , wherein said Fc region modification(s) comprises:
 (A) at least one substitution selected from the group consisting of:
 (1) F243L; 
 (2) D270E; 
 (3) R292P; 
 (4) S298N; 
 (5) Y300L; 
 (6) V305I; 
 (7) A330V; and 
 (8) P396L; 
   (B) at least one substitution of two amino acid residues selected from the group consisting of:
 (1) F243L and P396L; 
 (2) F243L and R292P; and 
 (3) R292P and V305I; 
   (C) at least one substitution of three amino acid residues selected from the group consisting of:
 (1) F243L, R292P and Y300L; 
 (2) F243L, R292P and V305I; 
 (3) F243L, R292P and P396L; and 
 (4) R292P, V305I and P396L; 
   (D) at least one substitution of four amino acid residues selected from the group consisting of:
 (1) F243L, R292P, Y300L and P396L; and 
 (2) F243L, R292P, V305I and P396L; 
   or   (E) a substitution of at least the five amino acid residues of F243L, R292P, Y300L, V305I and P396L.   
     
     
         25 . The method of  claim 24 , wherein said antibody comprises:
 (A) a light chain variable domain that comprises the amino acid sequences of SEQ ID NOs: 5, 7 and 9 and a heavy chain variable domain that comprises the amino acid sequences of SEQ ID NOs: 13, 15 and 17;   and   (B) an Fc region modification comprising the substitutions: L235V, F243L, R292P, Y300L, or P396L.   
     
     
         26 . The method of  claim 25 , wherein said antibody is a humanized antibody. 
     
     
         27 . The method of  claim 21 , wherein said antibody comprises:
 (A) a light chain variable domain comprising the amino acid sequence of SEQ ID NO:89;   (B) a heavy chain variable domain comprising the amino acid sequence of SEQ ID NO:99; and   (C) an Fc-region comprising the substitutions: L235V, F243L, R292P, Y300L, and P396L.   
     
     
         28 . The method of  claim 27 , wherein said cancer is selected from the group consisting of: an adrenal gland tumor, an AIDS-associated cancer, an alveolar soft part sarcoma, an astrocytic tumor, bladder cancer, bone cancer, a brain and spinal cord cancer, a metastatic brain tumor, a breast cancer, a carotid body tumors, a cervical cancer, a chondrosarcoma, a chordoma, a chromophobe renal cell carcinoma, a clear cell carcinoma, a colon cancer, a colorectal cancer, a desmoplastic small round cell tumor, an ependymoma, a Ewing's tumor, an extraskeletal myxoid chondrosarcoma, a gallbladder or bile duct cancer, gastric cancer, a gestational trophoblastic disease, a germ cell tumor, a head and neck cancer, hepatocellular carcinoma, an islet cell tumor, a Kaposi's Sarcoma, a kidney cancer, a leukemia, a liposarcoma/malignant lipomatous tumor, a liver cancer, a lymphoma, a lung cancer, a medulloblastoma, a melanoma, a meningioma, a multiple endocrine neoplasia, a multiple myeloma, a myelodysplastic syndrome, a neuroblastoma, a neuroendocrine tumors, an ovarian cancer, a pancreatic cancer, a papillary thyroid carcinoma, a parathyroid tumor, a pediatric cancer, a peripheral nerve sheath tumor, a pheochromocytoma, a pituitary tumor, a prostate cancer, a posterious uveal melanoma, a renal metastatic cancer, a rhabdoid tumor, a rhabdomyosarcoma, a sarcoma, a skin cancer, a soft-tissue sarcoma, a squamous cell cancer, a stomach cancer, a synovial sarcoma, a testicular cancer, a thymic carcinoma, a thymoma, a thyroid metastatic cancer, and a uterine cancer. 
     
     
         29 . The method of  claim 28 , wherein each of said one or more dose(s) is 1-100 mg/kg. 
     
     
         30 . The method of  claim 29 , wherein each of said one or more dose(s) is at least about 10 mg/kg. 
     
     
         31 . The method of  claim 30 , wherein said one or more dose(s) comprises at least two doses, and wherein said doses are administered about every 21 days from each other. 
     
     
         32 . The method of  claim 31 , further comprising administering an additional anti-cancer agent. 
     
     
         33 . A method of detecting circulating intact B7-H3 antigen, or a fragment thereof that retains the ability to be detected, in blood of a human subject, comprising:
 (i) forming a complex between said intact B7-H3 antigen or said fragment thereof, and an isolated antibody or an immunoreactive fragment thereof, wherein said antibody or said fragment thereof comprises a variable domain that specifically binds an extracellular domain of B7-H3 and comprises:
 (A) the amino acid sequences of SEQ ID NOs: 21, 23 and 25; or 
 (B) the amino acid sequences of SEQ ID NOs: 29, 31 and 33; and 
   (ii) detecting said formed complex.   
     
     
         34 . The method of  claim 33 , wherein said intact B7-H3 antigen or said fragment thereof is endogenously expressed on the surface of a cancer cell. 
     
     
         35 . The method of  claim 33 , wherein said antibody or said fragment thereof is detectably labeled. 
     
     
         36 . The method of  claim 33 , wherein said complex is formed in vitro. 
     
     
         37 . The method of  claim 33 , wherein said detecting is before or after said human subject has received any anti-cancer treatment. 
     
     
         38 . The method of  claim 37 , wherein said anti-cancer treatment is chemotherapy or radiation therapy. 
     
     
         39 . The method of  claim 33 , wherein said detecting is before or after administration of said antibody or said fragment thereof, wherein said antibody or said fragment thereof comprises:
 (A) a light chain variable domain comprising the amino acid sequence of SEQ ID NO: 89;   (B) a heavy chain variable domain comprising the amino acid sequence of SEQ ID NO: 99; and   (C) an Fc-region comprising the substitutions: L235V, F243L, R292P, Y300L, and P396L.   
     
     
         40 . The method of  claim 39 , wherein said formed complex is detected by enzyme-linked immunosorbent assay (ELISA), immunoprecipitation, immunofluorescence, enzyme immunoassay (EIA), immunohistochemistry, radioimmunoassay (RIA), Western blot analysis, or fluorescence activated cell sorting (FACS).