Composition comprising antibody that binds to domain ii of her2 and acidic variants thereof

Abstract

A composition comprising a main species HER2 antibody that binds to domain II of HER2 and acidic variants thereof is described. Pharmaceutical formulations comprising the composition, and therapeutic uses for the composition are also disclosed.

What is claimed is: 
     
         1 . A method of making a pharmaceutical composition comprising: (1) preparing a composition comprising a main species HER2 antibody that binds to domain II of HER2, and acidic variants thereof including glycated variant, disulfide reduced variant, or non-reducible variant, and (2) evaluating the acidic variants in the composition, and confirming that the amount thereof is less than about 25%. 
     
     
         2 . The method of  claim 1  wherein step (2) comprises evaluating the acidic variants by a method selected from the group consisting of ion exchange chromatography wherein the composition is treated with sialidase, reduced capillary electrophoresis with sodium dodecyl sulfate (CE-SDS), non-reduced CE-SDS, boronate chromatography, and peptide mapping. 
     
     
         3 . The method of  claim 1  wherein step (2) comprises evaluating the acidic variants by ion exchange chromatography. 
     
     
         4 . The method of  claim 3  which comprises cation exchange chromatography using a cation exchanger with a carboxylate functional group. 
     
     
         5 . The method of  claim 4  wherein the conditions for the chromatography involve:
 Buffer A of 20 mM BisTris, pH 6.0; Buffer B of 20 mM BisTris, 200 mM NaCl, pH 6.0; and a gradient of 0.5% Buffer B at 1.0 mL/min. 
 
     
     
         6 . The method of  claim 1  comprising combining the composition after step (2) with a pharmaceutically acceptable carrier. 
     
     
         7 . The method of  claim 1  wherein the composition evaluated in step (2) is in a pharmaceutically acceptable carrier.