From fed-batch to perfusion: Productivity and quality considerations for a late-stage program

In this poster, we will present the rapid development of a perfusion process with high productivity for late-stage manufacturing. The process uses a Chinese Hamster Ovary (CHO) cell line for monoclonal antibody production. Prior to the development, the clinical supply was manufactured by a fed-batch process with the same cell line. To achieve desired productivity and comparable quality attributes, we developed a repeated batch shake flask model to rapidly screen media and process conditions. Shake flasks were inoculated at 10 × 106 cells/mL and maintained in a CO2 incubator with medium exchange for every 48 hours, repeated for at least three times. Harvested culture samples were purified on an automated high-throughput purification platform for antibody quality attributes analysis. We observed that quality attributes such as N-linked glycans were comparable between the shake flask model and the perfusion process ran in 3 L bioreactors. Thus, the repeated batch shake flask model was used for Design of Experiments (DOE) or single factor experiments evaluating the impact of media components and process conditions on cell growth, productivity, and quality attributes. The top conditions were confirmed and optimized in 3 L perfusion bioreactors with an alternating tangential flow filtration system (ATF-2) for up to 50 days. By varying media and perfusion conditions, we were able to maintain steady state cell density at different levels of 45, 70 and 110 x 106 cells/mL with a range of productivity at 0.8 to 2.5 g/L/day at maximum perfusion rate of 1.5 vvd. The process efficiency and scalability were assessed. Perfusion culture conditions, such as perfusion rates and bleed rates, were evaluated for their effect on steady state cell density and productivity. Additionally, culture temperature and medium additives were evaluated to understand their impact on productivity and protein quality. As a result of these efforts, a high productivity perfusion process producing desired antibody was successfully developed