Improving Protein Purification: Application Of Excipients In Downstream Processing

The production of antibodies and Fc-fusion proteins involves several downstream processing unit operations. The widely used purification template with Protein A chromatography, virus inactivation at low pH, and subsequent ion exchange chromatography steps is mostly able to remove impurities like aggregates, host-cell proteins, and viruses, which could affect the safety and efficacy of the product.

The low pH elution during Protein A chromatography, as well as during virus inactivation may induce aggregation. Preventing protein aggregation during these unit operations instead of removing the multimeric forms during subsequent polishing steps would be a more efficient strategy. Excipients have shown that they can minimize aggregation levels in the final product formulation. For this reason, we have investigated the benefits of adding excipients during downstream processing on protein stability, chromatographic performance and viral inactivation.

This study shows that the addition of excipients have a beneficial effect of the purification during Protein A chromatography and virus inactivation, without harming the subsequent chromatographic steps.