Enhancing Protein A performance in mAb processing: A method to reduce and rapidly evaluate host cell DNA levels during primary clarification

The use and impact of 3M™ Emphaze™ AEX Hybrid Purifier, a single‐use, fully synthetic chromatographic product, was explored to reduce host cell DNA (HC‐DNA) concentration during the primary clarification of a monoclonal antibody (mAb). An approximately 5‐log reduction in HC‐DNA was achieved at an Emphaze AEX Hybrid Purifier throughput of 200 L/m2. The appreciable reduction in HC‐DNA achieved during primary clarification enhanced Protein A chromatography performance, resulting in a sharper and narrower elution profile. In addition, a 24× improvement in host cell protein (HCP) removal and fewer impurities nonspecifically bound to the Protein A column were observed compared to those resulting from the use of depth filtration for clarification. The use of a rapid, qualitative acidification assay to facilitate HC‐DNA monitoring was also investigated. This assay involves the acidification‐induced precipitation of HC‐DNA, enabling the easy and rapid detection of DNA breakthrough across purification media such as Emphaze AEX Hybrid Purifier by means of turbidimetric and particle size measurements.