Antibodies selective for cells presenting erbb2 at high density

Abstract

An erbB2 antibody is provided that binds preferentially to disease cells having an erbB2 density greater than a normal erbB2 density. The erbB2 antibody comprises a heavy chain and a light chain. Each chain has a constant region and a variable region. Each variable region comprises framework regions and complementarity determining regions (CDRs), wherein the CDRs have an amino acid sequence set forth below: For the heavy chain: CDR1 GFNIKDTYIH (SEQ ID No. 1) CDR2 RIYPTNGY 57 TR 59 YADSVKG (SEQ ID No. 2) CDR3 WGGDGFYAMDY (SEQ ID No. 3). For the light chain: CDR1 RASQDVN 30 TAVA (SEQ ID No. 4) CDR2 SASF 53 LYS (SEQ ID No. 5) CDR3 QQHY 92 TTPPT (SEQ ID NO. 6). At least one of Y57, R59, N30, F53, and Y92 is substituted by an amino acid that confers on said antibody a reduced erbB2 binding affinity (Kd) that is in the range from 0.1 nM to 100 nM. The substitution is other than N30A, F53N, Y92A and Y92F when there is a single substitution in the antibody light chain.

1 - 22 . (canceled) 
     
     
         23 . An antibody or a bivalent fragment thereof that binds preferentially to disease cells having an erbB2 density greater than a normal erbB2 density, the antibody comprising:
 a heavy chain (HC) comprising a complementarity determining region (CDR)1 comprising the sequence GFNIKDTYIH (SEQ ID NO: 1); a CDR2 comprising the sequence RIYPTNGY 57 TR 59 YADSVKG (SEQ ID NO: 2); and a CDR3 comprising the sequence WGGDGFYAMDY (SEQ ID NO: 3); and   a light chain (LC) comprising a CDR1 comprising the sequence RASQDVN 30 TAVA (SEQ ID NO: 4); a CDR2 comprising the sequence SASF 53 LYS (SEQ ID NO: 5); and a CDR3 comprising the sequence QQHY 92 TTPPT (SEQ ID NO. 6),   wherein the heavy chain and the light chain contain substitutions consisting of HC Y57A, LC F53N, and LC Y92A.   
     
     
         24 . An antibody according to  claim 23 , the antibody having the framework region sequences of trastuzumab. 
     
     
         25 . An antibody according to  claim 23 , the antibody having the framework region sequences and constant region sequences of trastuzumab. 
     
     
         26 . A bivalent fragment of an antibody according to  claim 23 . 
     
     
         27 . A conjugate comprising a cytotoxin or a detectable label and, conjugated thereto, an antibody or bivalent fragment thereof as defined according to  claim 23 . 
     
     
         28 . A pharmaceutical composition comprising a pharmaceutically acceptable carrier and an antibody in an amount useful to control the growth of cells presenting erbB2 at a density greater than the normal erbB2 density, in a subject in need thereof, wherein the antibody is an antibody or bivalent fragment thereof as defined according to  claim 23 . 
     
     
         29 . A method of treating a subject presenting with disease cells having an erbB2 density greater than normal, comprising treating the subject with a pharmaceutical composition comprising the antibody as defined according to  claim 23 . 
     
     
         30 . The method according to  claim 29 , wherein the disease cells are cancer cells. 
     
     
         31 . The method according to  claim 30 , wherein the cancer cells are breast cancer cells. 
     
     
         32 . An antibody or a bivalent fragment thereof comprising a heavy chain and a light chain, each chain having a constant region and a variable region, each variable region comprising framework regions and complementarity determining regions (CDRs), wherein:
 the heavy chain (HC) comprises a CDR1 comprising the sequence GFNIKDTYIH (SEQ ID NO: 1); a CDR2 comprising the sequence RIYPTNGY 57 TR 59 YADSVKG (SEQ ID NO: 2); and a CDR3 comprising the sequence WGGDGFYAMDY (SEQ ID NO: 3); and   the light chain (LC) comprises a CDR1 comprising the sequence RASQDVN 30 TAVA (SEQ ID NO: 4); a CDR2 comprising the sequence SASF 53 LYS (SEQ ID NO: 5); and a CDR3 comprising the sequence QQHY 92 TTPPT (SEQ ID NO. 6),   wherein the heavy chain and the light chain contain substitutions consisting of HC Y57A, LC F53N, and LC Y92A, and wherein the antibody further comprises the framework region sequences of trastuzumab.   
     
     
         33 . The antibody of according to  claim 32 , wherein the antibody further comprises the constant region sequence of trastuzumab. 
     
     
         34 . A pharmaceutical composition comprising the antibody or bivalent fragment of  claim 32 .