Compared to batch operation, continuous bioprocessing can offer numerous advantages, including increased productivity, improved process control, reduced footprint, and increased flexibility. However, integration of traditional batch operations into a connected process can be challenging. In contrast to batch operations run at constant pressure or high flux, virus filtration in continuous processes may be operated at very low flux. This change in operating conditions may reduce the viral retention performance of the filter which has inhibited adoption of truly continuous virus filtration. To overcome this limitation, a novel approach is described that utilizes serial virus filtration, with a high area ratio between first to second stage filters, to achieve virus retention targets. In this study, virus filters were operated continuously (except for planned process interruptions) for 200 hours in a serial configuration at a first to second stage filter area ratio of 13:1 and at a first stage flux of 5 L/m 2/hr. While the minute virus of mice (MVM) retention performance of the first stage filter was about 4 log reduction value (LRV), there was no virus detected in the second stage filtrate, translating to an MVM LRV across the filtration train of ≥6.7. The second stage filter was the dominant flow resistance at the start of the run but, as it was protected from foulants by the first stage filter, it suffered minimal fouling and the life of the filter train was controlled by the first stage. A theoretical case study projected that continuous virus filtration using serial configuration at high area ratio would have about 30% longer filter changeout time, 14% higher productivity, and virus retention nearly 6 LRV greater than single stage operation. The findings of this research are expected to provide valuable insights into optimizing virus filtration in continuous bioprocessing.

Detergent-mediated viral inactivation is an important process step for ensuring viral safety of parenteral biotherapeutics, including plasma proteins and monoclonal antibodies (mAb). The conventional Triton™ X-100 detergent has ecological toxicity concerns and REACH classification that mandate replacement in the biopharmaceutical industry. Criteria for a replacement detergent include viral inactivation efficacy, acceptable safety and biodegradation profile, process removal and quality suitable for parenteral drug product manufacturing. A non-ionic, C11-15 secondary alcohol ethoxylate, Deviron ® 13-S9 detergent, has been demonstrated to meet the necessary requirements for detergent performance. Benchmarking studies with Triton™ X-100 demonstrate comparable performance with a panel of enveloped viruses in multiple matrices, including human IgG, clarified cell culture harvest, and fractionated plasma. Deviron ® 13-S9 detergent demonstrated viral inactivation efficiency comparable to or better than, Triton™ X-100 detergent, achieving > 5 log reduction values (LRV). Critical micelle concentration (CMC) was determined across different temperatures and media. Deviron ® 13-S9 detergent was demonstrated to be readily biodegradable according to OECD 301B guidelines. Effective removal with typical chromatography processes used in downstream purification was confirmed. These findings support Deviron ® 13-S9 detergent as a viable alternative to Triton™ X-100 detergent, ensuring robust viral inactivation, environmental compatibility, and alignment with regulatory requirements.