Top-Down Characterization of Protein Pharmaceuticals by Liquid Chromatography/Mass Spectrometry: Application to Recombinant Factor IX Comparability– A Case Study

Abstract

Recombinant protein pharmaceuticals have revolutionized the treatment of a variety of medical ailments, including cancer, autoimmune diseases, and hemostatic disorders. Proteins manufactured with eukaryotic expression systems may be complex and heterogeneous because of posttranslational modifications (PTMs) and differential proteolytic processing. At one time, detailed characterization and definition of the protein structure were difficult, and the manufacturing process defined the product. If process changes were made, clinical trials were required to demonstrate product equivalence prior to regulatory agency acceptance of the product manufactured by the modified process. To adopt new manufacturing processes in a timely manner, the biopharmaceutical industry and regulatory agencies have worked together over the last few years to develop new guidance documents based on knowledge gained from industry experience in the manufacture and clinical testing of protein pharmaceuticals (1,2). Manufacturers of protein pharmaceuticals consistently strive to deliver the highest quality product in a cost-efficient manner. This can be accomplished through optimization of the production process and incorporation of new technologies to enhance product purity and yield. Process improvements may include a change of the host cell line, enhancement of the cell culture medium or cell culture management, or modifications to the purification process. In some cases, an additional manufacturing site is brought online to augment production capacity.