This peer-reviewed paper outlines the risk of aerotolerant anaerobic bacterial contamination during the manufacture of biologic drug substance and the challenges of detection. It examines the issues that manufacturers may consider regarding anaerobic bioburden testing during mammalian cell culture biologics processing, focusing on the detection of aerotolerant anaerobes. It also contains case studies from multiple biopharmaceutical companies, which detected Cutibacterium acnes (C. acnes), the primary anaerobe of concern.
A survey of the BioPhorum Microbial Control Workstream found that more than half of the participants reported contamination events with C. acnes. This survey reported variability in the ability of the compendial microbial enumeration tests to detect C. acnes, thus presenting a challenge for bulk biologics manufacturers. This paper recommends testing conditions designed to increase the likelihood of detecting aerotolerant anaerobe contaminations.