Challenges and approaches in demonstrating comparability of a well-characterized biotechnology product after manufacturing changes can be as varied and complex as the products themselves. Participants at the January 2005 CMC Strategy Forum sought to discuss and agree on common implementation strategies for different manufacturing change scenarios (1). Development of flexible, comprehensive approaches in strategy development addressed evaluation of critical product characteristics, appropriate process steps to test, numbers of lots and levels of testing required, and assessment of product comparability. The…
Tuesday, November 17, 2015 Daily Archives
Special Report on Assays, Test Methods, and Comparability The CMC Strategy Forum Series, Part 4, The Roles of Bioactivity Assays in Lot Release and Stability Testing
A January 2007 CMC Strategy Forum on the roles of bioactivity assays in lot release and stability testing was held in Washington, DC (1). Its purpose was to promote an understanding of the design and utility of bioassays throughout product development and to delineate the conditions under which surrogate assays could be used to determine product potency. Topics of discussion included appropriate assay selection at each stage of product development, the potential use of binding assays for potency testing, and…
Development and Optimization of CHOgro® Transient Expression Technologies for High Titer Antibody Production in Suspension CHO Cells
During early stage drug development, quickly obtaining relevant candidate proteins through transient transfection can accelerate drug dis-covery. High titers are often obtained from Human Embryonic Kidney (HEK) 293 derived cell types; however, the use of different host cells between early stage transient and later stable protein production is a concern and can lead to the advancement of false-positive candidates. Chinese hamster ovary (CHO) cells are a desirable target cell type due to growth characteristics and a history of regulatory approval;…
Development of a Novel Cold Chain Tubing, FP-FLEX™, and Single- Use Freezing Bag for Working Cell Banks Enabling Closed-System Processing to Temperatures as Low as -196°C
Working cell banks (WCB’s) are commonly applied to initiate cell culture manufacturing campaigns for production of therapeutic proteins. These campaigns typically begin with inoculation of cells previously cryopreserved in vials. While vials are typically used to establish WCB’s and initiate manufacturing campaigns, they are not optimal for the growing demands of commercial production. Vials are small and filling/removal is performed through an open cap. This process leads to numerous manual operations and culture vessels, resulting in contamination risks and potential…