Anti-cd228 antibodies and antibody-drug conjugates

Abstract

Provided are novel anti-CD228 antibodies and antibody-drug conjugates and methods of using such anti-CD228 antibodies and antibody-drug conjugates to treat cancer.

1 . An isolated anti-CD228 antibody, or antigen-binding fragment thereof, comprising a heavy chain variable region and a light chain variable region, wherein the heavy chain variable region comprises:
 (i) a CDR-H1 comprising the amino acid sequence of SEQ ID NO:1;   (ii) a CDR-H2 comprising the amino acid sequence of SEQ ID NO:2; and   (iii) a CDR-H3 comprising the amino acid sequence of SEQ ID NO:3; and   
       wherein the light chain variable region comprises:
 (i) a CDR-L1 comprising the amino acid sequence of SEQ ID NO:4; 
 (ii) a CDR-L2 comprising the amino acid sequence of SEQ ID NO:5; and 
 (iii) a CDR-L3 comprising the amino acid sequence of SEQ ID NO:6. 
 
     
     
         2 . The antibody or antigen-binding fragment of  claim 1 , wherein the antibody is humanized. 
     
     
         3 . A humanized anti-CD228 antibody, or antigen-binding fragment thereof, comprising a heavy chain variable region comprising an amino acid sequence at least 90% identical to SEQ ID NO: 7 provided that position H27 is occupied by D, position H30 is occupied by T, position H47 is occupied by Y, position H71 is occupied by R, and position H78 is occupied by Y, and a light chain variable region comprising an amino acid sequence at least 90% identical to SEQ ID NO: 8, provided that position L2 is occupied by F, position L36 is occupied by Y and position L46 is occupied by L. 
     
     
         4 - 5 . (canceled) 
     
     
         6 . The antibody or antigen-binding fragment of  claim 1 , wherein the heavy chain variable region comprises an amino acid sequence having at least 95% sequence identity to the amino acid sequence of SEQ ID NO: 7 and the light chain variable region comprises an amino acid sequence having at least 95% sequence identity to the amino acid sequence of SEQ ID NO: 8. 
     
     
         7 - 17 . (canceled) 
     
     
         18 . An antibody-drug conjugate comprising the antibody or antigen-binding fragment of  claim 1  conjugated to a cytotoxic or cytostatic agent. 
     
     
         19 - 20 . (canceled) 
     
     
         21 . The antibody-drug conjugate of  claim 18 , wherein the cytotoxic or cytostatic agent is a monomethyl auristatin. 
     
     
         22 - 25 . (canceled) 
     
     
         26 . A nucleic acid encoding the heavy chain variable region and/or the light chain variable region of the anti-CD228 antibody, or antigen-binding fragment thereof, of  claim 1 . 
     
     
         27 . A vector comprising the nucleic acid of  claim 26 . 
     
     
         28 . (canceled) 
     
     
         29 . A host cell comprising the nucleic acid of  claim 26 . 
     
     
         30 . (canceled) 
     
     
         31 . A method of producing an anti-CD228 antibody or antigen-binding fragment thereof comprising culturing the host cell of  claim 29  under a condition suitable for production of the anti-CD228 antibody or antigen-binding fragment thereof. 
     
     
         32 . (canceled) 
     
     
         33 . A method of producing an anti-CD228 antibody-drug conjugate comprising culturing a host cell comprising a nucleic acid encoding the heavy chain variable region and/or the light chain variable region of an anti-CD228 antibody, or antigen-binding fragment thereof, under a condition suitable for production of the anti-CD228 antibody, or antigen-binding fragment thereof; isolating the anti-CD228 antibody, or antigen-binding fragment thereof, produced from the host cell; and conjugating the anti-CD228 antibody, or antigen-binding fragment thereof, to a cytotoxic or cytostatic agent, wherein the anti-CD228 antibody, or antigen-binding fragment thereof, comprises the heavy chain variable region and the light chain variable region, wherein the heavy chain variable region comprises:
 (i) a CDR-H1 comprising the amino acid sequence of SEQ ID NO:1,   (ii) a CDR-H2 comprising the amino acid sequence of SEQ ID NO:2,   (iii) a CDR-H3 comprising the amino acid sequence of SEQ ID NO:3; and   
       wherein the light chain variable region comprises:
 (i) a CDR-L1 comprising the amino acid sequence of SEQ ID NO:4, 
 (ii) a CDR-L2 comprising the amino acid sequence of SEQ ID NO:5, and 
 (iii) a CDR-L3 comprising the amino acid sequence of SEQ ID NO:6. 
 
     
     
         34 - 35 . (canceled) 
     
     
         36 . The method of  claim 33 , wherein the cytotoxic or cytostatic agent is a monomethyl auristatin. 
     
     
         37 - 40 . (canceled) 
     
     
         41 . A method of treating cancer in a subject, the method comprising administering to the subject the antibody or antigen-binding fragment of  claim 1 . 
     
     
         42 - 87 . (canceled) 
     
     
         88 . A kit comprising:
 (a) the antibody or antigen-binding fragment of  claim 1 ; and   (b) instructions for using the antibody or antigen-binding fragment in a method of treating cancer in a subject, the method comprising administering to the subject the antibody or antigen-binding fragment.   
     
     
         89 . A pharmaceutical composition comprising the antibody or antigen-binding fragment of  claim 1  and one or more agents selected from the group consisting of a physiologically acceptable carrier, a diluent, an excipient and an auxiliary.