(511a) Coupling Clarification and Purification Into a Single Unit Operation for Improved High-Titer Mammalian-Based Processing

Previous work has demonstrated that control of mammalian cell broth solution conditions during the production of therapeutic proteins can improve clarification performance using tangential flow filtration. There is, however, limited understanding of the effects of harvest conditions on clarification performance using centrifugation, including the impact on the subsequent purification steps. We present a framework for describing the performance of disc-stack centrifugation in conjunction with depth filtration for cell and impurity removal using controlled harvest conditions. Data from bench (2L-200L) to large-scale (2000 - 20,000L) operations is presented, evaluating the impact of controlled parameters on downstream performance.

Settling experiments of unclarified harvest media were performed at various buffer conditions. Turbidity, product titer, and impurity assays were performed on the supernatant in order to establish optimal harvest feed conditions prior to clarification. Pilot-scale centrifugation and depth filtration studies were then performed at a wide-range of centrifuge flowrates and RPMs using the optimized harvest conditions from various clinical products. The data showed a significant reduction in centrate clarity compared to clarifying with unadjusted harvest streams at all scales, with improved post-centrifuge filtration capacity, clarity and purity. Overall, this analysis allows for improved future design and optimization of large-scale centrifugal operations for processing mammalian cell culture broths.