Glucuronylation as a new acidic post-translational modification on therapeutic monoclonal antibodies

Abstract

Compositions and methods for identifying glucuronylated protein drug products are provided.

1 - 6 . (canceled) 
     
     
         7 . A protein drug product comprising a therapeutic protein, wherein less than 10% of the therapeutic protein's amino acids are glucuronylated. 
     
     
         8 . The protein drug product of  claim 7 , wherein less than 5% of the therapeutic protein's amino acids are glucuronylated. 
     
     
         9 . The protein drug product of  claim 7 , wherein the amino acids are lysine amino acids. 
     
     
         10 . The protein drug product of  claim 7 , wherein the therapeutic protein is an antibody or fusion protein. 
     
     
         11 . The protein drug product of  claim 10 , wherein the antibody is a monoclonal antibody or an antigen binding fragment thereof. 
     
     
         12 . A protein drug product comprising a therapeutic protein, wherein less than 3% of lysine amino acids of the therapeutic protein are glucuronylated. 
     
     
         13 . A method for increasing purity of a protein drug product comprising:
 analyzing the protein drug product to identify glucuronylation on a primary amine of one or more amino acids of the protein drug product; and   removing glucuronylated proteins from the protein drug product to produce a purified protein drug product.   
     
     
         14 . The method of  claim 13 , wherein the glucuronylated proteins are removed by high performance liquid chromatography techniques. 
     
     
         15 . The method of  claim 14 , wherein the chromatography techniques are selected from the group consisting of size exclusion chromatography, ion exchange chromatography, affinity chromatography, and combinations thereof. 
     
     
         16 . The method of  claim 15 , wherein the chromatography technique is coupled with mass spectroscopy analysis. 
     
     
         17 . The method of  claims 13 , wherein the amino acids are lysine amino acids. 
     
     
         18 . The method of  claim 13 , wherein the therapeutic protein is an antibody or fusion protein. 
     
     
         19 . The method of  claim 18 , wherein the antibody is a monoclonal antibody or an antigen binding fragment thereof. 
     
     
         20 . A method for identifying post-translationally modified protein drug product comprising:
 assaying a protein drug product obtained from a mammalian cell culture for glucuronylation, wherein the presence of glucuronylation of the protein drug product indicates that the protein drug product comprises post-translational modifications.   
     
     
         21 . The method of  claim 20 , wherein the mammalian cell culture comprising Chinese Hamster Ovary cells. 
     
     
         22 . The method of  claim 20 , wherein the glucuronylation is on lysine amino acids of the protein drug product. 
     
     
         23 . The method of  claim 20 , wherein the protein drug product is an antibody or fusion protein. 
     
     
         24 . The method of  claim 23 , wherein the antibody is a monoclonal antibody or an antigen binding fragment thereof.