The sterile hold time depends on the sterilization wrapping system, operator performance and sterilization cycle performance. After sterilization occurs, parts and equipment are to be used within a timeframe that is tested and validated. This allowable hold time is established for each sterilized item and associated sterilization wrapping system and is generally confirmed by an aseptic process simulation (APS). Benchmarking was completed of manufacturers within the pharma and biopharma industry to determine if common practices exist for establishing hold times for autoclaved items used within aseptic fill/finish manufacturing.
Established hold time is confirmed by using “expired” parts installed on the filling line or in aseptic filling operations as part of the routine APS. Using sterilized parts at the end of the hold time in the APS confirms the parts remain sterile through the expiry period. The hold time studies allow for sterile parts storage, thereby eliminating the need to sterilize materials the same day as the filling process.
For items required to be sterile, sterilization wrapping (bags and pouches) allows for steam penetration during autoclaving and maintains a microbial barrier post sterilization. The wrapping allows for parts and equipment to be moved throughout the facility and within the clean rooms without compromising the critical product contacting surfaces. Double wrapping or using a wrapping material that is compatible with manual application of surface disinfectants are both recommended methods of reducing risk during material transfer into higher classified spaces. For these reasons, defining the sterilization wrapping system (material of construction and closure method) is essential.
To test and confirm sterilization wrapping system performance, studies have been conducted using various bags, pouches, and closure methods over a defined hold time of 30 days. Biological indicators were used to confirm sterilization at time zero and sterility testing was performed throughout the hold time duration.
