Gamma Sterilization Product Update

I am updating a gamma sterilized product (carton with sterile pouch and IFU inside) to increase the size of the IFU by 2x. The original validation did not account for IFU size increases. Per ISO 11137-2, bioburden is the driver for the sterilization dose, not density or other factors. Since the bioburden in the sterile barrier did not change, does it make sense that the validation is not impacted and only the dose map would need to be verified due to the density increase?

IFU bioburden will be double, so average bioburden will be increased. This changes verificatin dose. For methode 1, sterilization dose goes a bit higher.

IFU bioburden might be only relevant if the IFU has to be terminally sterilised with an SAL of 10exp(6), e.g. is co-packaged into the sterile barrier system together with the actual medical device. The original request ("carton with sterile pouch and IFU inside") indicates that the IFU is not co-packed. Thus, only the density of the load presented to the irradiation cycle may change, and verification of the (continued) validity of the existing dose mapping may be appropriate. In case the dose-mapping experiment shows that the load density has a significant impact on the dose distribution in the load, further re-validation activities might be warranted according to ISO 11137-1, section 12.5.2, Assessment of change in product.

HTH,