Over Kill Approach
The Over Kill, Half Cycle sterilization validation process approach is designed to demonstrate lethality at the order of (-6) and will include number of sterilization cycles:
Fractional cycle - to demonstrate product sterility and validate the adequacy of the selected planted reference biological indicators - internal process device (IPCD) and external process devices (EPCD) during fractional exposure duration. Multiple IPCD’s and EPCD’s are used. Adequacy of PCD’s is such that after fractional cycle, the product arranged within the chamber as define in the process protocol must be found sterile, some but not all IPCD’s are found sterile and some EPCD’s but not less than IPCD’s are found sterile.
Half Cycle – a cycle during which all IPCD’s are found sterile. In this cycle product arrangement in the chamber and IPCD’s are exposed to half time of the defined cycle time to verify excess lethality as compared to fractional cycle. This cycle is repeated 3 times.
Full Cycle – after full time exposure to the product load Eto and ECH residuals and LAL are measured, bio burden is validated by correction factor and sterility test as executed following the fraction cycle is validated by re-testing product for sterility.
As part of each stage, and for validating that performance are met according to essential requirements, verification tests are executed, among which laboratory test for bio burden after packing, sterility, EtO residuals, and mechanical tests