Non-platelet depleting and non-red blood cell depleting cd47 antibodies and methods of use thereof

Abstract

This invention relates generally to monoclonal antibodies that recognize CD47, more specifically to CD47 antibodies that do not cause a significant level of agglutination of cells, red blood cell depletion, anemia, and/or platelet depletion, to methods of generating these antibodies, and to methods of using these monoclonal antibodies as therapeutics.

What is claimed is: 
     
         1 . An isolated monoclonal antibody that binds to CD47 or an immunologically active fragment thereof, wherein the antibody does not cause a significant level of red blood cell depletion, anemia, or both red blood cell depletion and anemia after administration. 
     
     
         2 . The isolated monoclonal antibody of  claim 1 , wherein the antibody does not cause a significant level of platelet depletion after administration. 
     
     
         3 . The isolated monoclonal antibody of  claim 1 , wherein the antibody does not cause a significant level of agglutination of cells after administration. 
     
     
         4 . The antibody of  claim 1 , wherein the antibody is chimeric, humanized, or fully human. 
     
     
         5 . The antibody of  claim 1 , wherein the CD47 is human CD47. 
     
     
         6 . The antibody of  claim 1 , wherein the antibody or immunologically active fragment thereof prevents CD47 from interacting with signal-regulatory-protein α (SIRPα). 
     
     
         7 . The antibody of  claim 6 , wherein the antibody or immunologically active fragment thereof promotes macrophage-mediated phagocytosis of a CD47-expressing cell. 
     
     
         8 . The antibody of  claim 1 , wherein the antibody or immunologically active fragment thereof is an IgG isotype selected from the group consisting of IgG1 isotype, IgG2 isotype, IgG3 isotype, and IgG4 isotype. 
     
     
         9 . The antibody of  claim 1 , wherein the antibody or immunologically active fragment thereof comprises a variable heavy (VH) chain region selected from the group consisting of SEQ ID NOs: 5-30. 
     
     
         10 . The antibody of  claim 1 , wherein the antibody or immunologically active fragment thereof comprises a variable light (VL) chain region selected from the group consisting of SEQ ID NOs: 31-47. 
     
     
         11 . The antibody of  claim 1 , wherein the antibody or immunologically active fragment thereof comprises a VH region provided in any one of SEQ ID NOs: 5-30 and a VL region provided in any one of SEQ ID NOs: 31-47. 
     
     
         12 . The antibody of  claim 11 , wherein the antibody or immunologically active fragment thereof comprises a VH region provided in any one of SEQ ID NOs: 5, 7, 8, 11, 12, 15-17, 20-22, and 27-30 paired with a VL region provided in any one of SEQ ID NOs: 31, 32, 35, 40, 41, 42, 43, 44, and 47. 
     
     
         13 . The antibody of  claim 11 , wherein the antibody comprises a combination of a VH chain region and a VL chain region selected from the combinations listed in Table 1. 
     
     
         14 . The antibody of  claim 1 , wherein the antibody or immunologically active fragment thereof comprises a VH complementarity determining region 1 (CDR1) sequence set forth in SEQ ID NO: 50, SEQ ID NO: 57, SEQ ID NO: 58, SEQ ID NO: 59, SEQ ID NO: 60, SEQ ID NO: 61, SEQ ID NO: 62, SEQ ID NO: 63, SEQ ID NO: 64, SEQ ID NO: 65, or SEQ ID NO: 66, a VH CDR2 sequence set forth in SEQ ID NO: 51, SEQ ID NO: 72, SEQ ID NO: 73, SEQ ID NO: 74, SEQ ID NO: 75, or SEQ ID NO: 76, a VH CDR3 sequence set forth in SEQ ID NO: 52 or SEQ ID NO: 77, a VL CDR1 sequence set forth in SEQ ID NO: 53, SEQ ID NO: 67, or SEQ ID NO: 68, a VL CDR2 sequence set forth in SEQ ID NO: 54, SEQ ID NO: 69, SEQ ID NO: 70, or SEQ ID NO: 71 and a VL CDR3 sequence set forth in SEQ ID NO: 55. 
     
     
         15 . The antibody of  claim 14 , wherein the antibody or immunologically active fragment thereof comprises a VH CDR1 sequence set forth in SEQ ID NO: 50, a VH CDR2 sequence set forth in SEQ ID NO: 51, a VH CDR3 sequence set forth in SEQ ID NO: 52, a VL CDR1 sequence set forth in SEQ ID NO: 53, a VL CDR2 sequence set forth in SEQ ID NO: 54, and a VL CDR3 sequence set forth in SEQ ID NO: 55. 
     
     
         16 . The antibody of  claim 14 , wherein the antibody or immunologically active fragment thereof comprises a VH CDR1 sequence set forth in SEQ ID NO: 50, a VH CDR2 sequence set forth in SEQ ID NO: 72, a VH CDR3 sequence set forth in SEQ ID NO: 52, a VL CDR1 set forth in SEQ ID NO: 53, a VL CDR2 sequence set forth in SEQ ID NO: 71, and a VL CDR3 sequence set forth in SEQ ID NO: 55. 
     
     
         17 . The antibody of  claim 1 , wherein the antibody binds to CD47 in a head to side orientation, wherein a VH chain of the antibody is positioned near the membrane of a CD47 expressing cell, and wherein a VL chain of the antibody occludes a SIRPα binding site on CD47. 
     
     
         18 . The antibody of  claim 1 , wherein the antibody binds to CD47 in a head to side orientation, wherein a VL chain of the antibody is positioned near the membrane of a CD47 expressing cell, and wherein a VH chain of the antibody occludes a SIRPα binding site on CD47. 
     
     
         19 . The antibody of  claim 1 , wherein the antibody binds to a discontinuous epitope on CD47. 
     
     
         20 . The antibody of  claim 19 , wherein the antibody binds to a CD47 loop comprising SEQ ID NO: 56. 
     
     
         21 . The antibody of  claim 19 , wherein the discontinuous epitope comprises amino acids residues Y37, K39, K41, K43, G44, R45, D46, D51, H90, N93, E97, T99, E104, or E106 of CD47 when numbered in accordance with SEQ ID NO: 147. 
     
     
         22 . The antibody of  claim 3 , wherein the antibody does not cause a significant level of hemagglutination of red blood cells after administration. 
     
     
         23 . The antibody of  claim 1 , wherein the antibody or immunologically active fragment thereof is an IgG isotype selected from IgG4P and IgG4PE. 
     
     
         24 . A pharmaceutical composition comprising the antibody of  claim 1  or an immunologically active fragment thereof and a carrier. 
     
     
         25 . A method of alleviating a symptom of a cancer or other neoplastic condition, the method comprising administering the antibody of  claim 1  or an immunologically active fragment thereof to a subject in need thereof in an amount sufficient to alleviate the symptom of the cancer or other neoplastic condition in the subject. 
     
     
         26 . The method of  claim 25 , wherein the subject is a human. 
     
     
         27 . The method of  claim 25 , wherein the antibody is chimeric, humanized, or fully human. 
     
     
         28 . The method of  claim 25 , wherein the CD47 is human CD47. 
     
     
         29 . The method of  claim 25 , wherein the antibody or immunologically active fragment thereof prevents CD47 from interacting with SIRPα. 
     
     
         30 . The method of  claim 25 , wherein the antibody or immunologically active fragment thereof is an IgG isotype selected from the group consisting of IgG1 isotype, IgG2 isotype, IgG3 isotype, and IgG4 isotype. 
     
     
         31 . The method of  claim 25 , wherein the antibody or immunologically active fragment thereof is an IgG isotype selected from IgG4P and IgG4PE. 
     
     
         32 . The method of  claim 25 , further comprising administering chemotherapy. 
     
     
         33 . The method of  claim 32 , wherein said chemotherapy is radiotherapy. 
     
     
         34 . The method of  claim 25 , wherein the antibody is administered to the subject at a dose of at least 10 mg/kg. 
     
     
         35 . The method of  claim 25 , wherein the antibody is administered to the subject at a dose of at least 30 mg/kg.