Biopharmaceutical Industry Approaches to Facility Segregation for Viral Safety: An Effort from the Consortium on Adventitious Agent Contamination in Biomanufacturing

Appropriate segregation within manufacturing facilities is required by regulators and utilized by manufacturers to ensure that the final product has not been contaminated with 1) adventitious viruses, 2) another pre-/ post-viral clearance fraction of the same product, or 3) with another product processed in the same facility. However, there is not consensus on what constitutes appropriate facility segregation to minimize these risks. In part, this is due to the fact that a wide variety of manufacturing facilities and operational practices exist, including single and multi-product manufacturing, using traditional segregation strategies with separate rooms for specific operations that may use stainless steel or disposable equipment to more modern ballroom style operation that use mostly disposable equipment (i.e. pre- and post-viral clearance manufacturing operations are not physically segregated by walls). Further, there is a lack of consensus around basic definitions and approaches related to facility segregation. For example, given that several unit operations provide assurance of virus clearance during downstream processing, how does one define pre- and post-viral clearance and at which point(s) should a viral segregation barrier be introduced? What is a “functionally closed” system? How can interventions be conducted so that the system remains “functionally closed”? How can “functionally closed” systems be used to adequately isolate a product stream and ensure its safety? To address these issues, the member companies of the Consortium on Adventitious Agent Contamination in Biomanufacturing (CAACB) have conducted a facility segregation project with the following goals: define “pre- and post-viral clearance zones” and “pre- and post-viral clearance materials”; define “functionally closed” manufacturing systems; and identify an array of facility segregation approaches that are used for the safe and effective production of recombinant biologics as well as plasma products. This article reflects the current thinking from this collaborative endeavor.