FAQ: Sterility Assurance for Injectable Biologics

European Union good manufacturing practice (GMP) Annex 1 states that finished products should be terminally sterilized where possible, because a validated terminal step provides greater sterility assurance than sterile filtration or aseptic processing.¹ FDA's aseptic processing guidance is similarly direct, recommending that sterile drugs should be made by aseptic processing only when terminal sterilization is not feasible.² For many biologics this step is not feasible because heat or radiation can damage the molecule. The product, container, and closure are sterilized separately and combined in a tightly controlled environment, so sterility assurance depends on facility design, process controls, and operator behavior.² US sterile manufacturing also falls under broader current GMP (cGMP) requirements, which was outlined earlier by Regulatory Compliance Associates’s Susan J. Schniepp in an overview of cGMPs for sterile manufacturing.³