Optimization of the medium perfusion rate in a packed-bed bioreactor charged with CHO cells

Abstract

In the present study, the optimal medium perfusion rate to be used for the continuous culture of a recombinant CHO cell line in a packed-bed bioreactor made of Fibra-Cel Ò disk carriers was determined. A first-generation process had originally been designed with a high perfusion rate, in order to rapidly produce material for pre-clinical and early clinical trials. It was originally operated with a perfusion of 2.6 vvd during production phase in order to supply the high cell density ($2.5 · 10 7 cell ml À1 of packed-bed) with sufficient fresh medium. In order to improve the economics of this process, a reduction of the medium perfusion rate by À25% and À50% was investigated at small-scale. The best option was then implemented at pilot scale in order to further produce material for clinical trials with an improved second-generation process. With a À25% reduction of the perfusion rate, the volumetric productivity was maintained compared to the first-generation process, but a À30% loss of productivity was obtained when the medium perfusion rate was further reduced to À50% of its original level. The protein quality under reduced perfusion rate conditions was analyzed for purity, N-glycan sialylation level, abundance of dimers or aggregates, and showed that the quality of the final drug substance was comparable to that obtained in reference conditions. Finally, a reduction of À25% medium perfusion was implemented at pilot scale in the second-generation process, which enabled to maintain the same productivity and the same quality of the molecule, while reducing costs of media, material and manpower of the production process. For industrial applications, it is recommended to test whether and how far the perfusion rate can be decreased during the production phase -provided that the product is not sensitive to residence time -with the benefits of reduced cost of goods and to simplify manufacturing operations.

Perfusion Processes

“…In order to reduce the COGS of a sub-optimal process developed to produce the material for early clinical trial, Meuwly et al (2004) studied the effect of decreasing the perfusion rate of a CHO cell-based process in packed-bed bioreactor. He observed that a 25 % reduction compared to the original level was satisfying for the yield and quality of POI while 50 % reduction caused a 30 % productivity loss however without alteration of the quality.…”

“…A sub-optimal process, requiring limited efforts, can be acceptable for a rapid POI production for Discovery/Research, in the case of a process developed for pre-clinical and early clinical phases under hard time constraints. The process can then be further optimized in preparation for the commercial phase (Meuwly et al 2004). More work will be needed when Fig.…”

Influence of specific growth rate on specific productivity and glycosylation of a recombinant avidin produced by a Pichia pastoris Mut+ strain

“…While major glycosylation changes and optimizations are generally effectuated at the genome level, some bioprocess parameters can also influence the structure and homogeneity of the carbohydrate moiety, both during cultivation and purification (Goochee and Monica, 1990;Jenkins et al, 1996). The effect on glycosylation of cultivation parameters such as glucose starvation, pH, perfusion rate, temperature or batch length have been investigated in details for mammalian cells (Andersen et al, 2000;Meuwly et al, 2004;Yuen et al, 2003). Similar studies on product quality were performed with P. pastoris, but rather than investigating glycosylation, they concentrated on protein activity or level of aggregation.…”

Bioengineering Outlook on Cultivated Meat Production

“…Development of biotechnological processes in general, with a special emphasis on animal cell culture, is aimed at defining bioprocess solutions that warrant high volumetric productivity, batch-to-batch consistency and homogenous product quality at low costs [ 179 ]. Walther et al [ 180 ] have recognized two major needs for future biomanufacturing: increased flexibility and reduced cost of goods.…”