Enhancing rapid Protein A performance in monoclonal antibody processing: Anion exchange chromatographic clarification

Clarification fidelity, including reduction of insoluble and soluble contaminants, has been demonstrated to significantly affect the performance and robustness of the Protein A capture chromatography step during the purification of monoclonal antibodies (mAb) and their derivatives expressed in CHO cell cultures. While the vast majority of previous studies have focused on the evaluation of these effects on conventional Protein A resins, in this study, we evaluated such effects on the new membrane- and fiber-based Protein A technologies. Both depth filtration and chromatographic clarification using charged functional fiber approaches have been studied, and we evaluated the effects of these methods on convective Protein A technology cycling robustness, as well as the purity of the product in the elution pool with respect to process-related contaminants. We found that clarification of CHO cell culture using anion exchange (AEX) fiber significantly increases the purity of the mAb in the elution pool with respect to host cell protein (at least 50% less) and DNA (>2 log less) as well as enables a higher number of Protein A cycles (at least 2X increase in fiber-based Protein A cycling lifetime) compared to CHO cell culture fluid clarified with conventional depth filtration. It is likely that this is due to superior DNA and sub-500 nm particle reduction during the chromatographic fiber clarification. This work elucidates the importance of a holistic process strategy when designing a biopharmaceutical purification process.