Characterizing and enhancing virus removal by protein A chromatography

Area of Science:

• Biopharmaceutical manufacturing
• Downstream processing
• Viral clearance

Background:

• Protein A chromatography is crucial for capturing Fc-containing biopharmaceuticals but often shows variable virus removal.
• Previous studies suggested feedstock components influence virus removal efficiency.
• Understanding product-specific effects on virus clearance is essential for process optimization.

Purpose of the Study:

• To investigate the impact of monoclonal antibody (mAb) products on virus partitioning during Protein A chromatography.
• To identify factors contributing to low virus log reduction values (LRVs) in specific mAb products.
• To explore strategies for improving virus removal in Protein A chromatography.

Main Methods:

• Partitioning of three virus types (retrovirus-like particles, xenotropic murine leukemia virus, murine minute virus) on Eshmuno® A columns was studied using pure mAbs.
• High throughput screening (HTS) methods with Eshmuno® A resin plates were employed to identify potential excipients.
• Analysis focused on the influence of mAb products versus other cell culture impurities on virus removal.

Main Results:

• Low virus LRVs in Protein A chromatography were correlated with the presence of specific mAb products, altering virus partitioning.
• The partitioning trend for retrovirus-like particles and xenotropic murine leukemia virus was consistent, while murine minute virus showed a slightly different pattern.
• Excipients with ionic and hydrophobic properties were identified via HTS as capable of mitigating mAb-induced reductions in LRV.

Conclusions:

• Monoclonal antibody products themselves are a significant factor in reduced virus removal during Protein A chromatography.
• Both ionic and hydrophobic interactions are implicated in the mechanism of altered virus partitioning.
• High throughput screening is a valuable tool for identifying excipients that can enhance viral clearance in Protein A processes, offering guidance for process optimization.