Bioequivalence and Bioavailability Forum

Dear Keath
The FDA guideline states that as a general rule the quantity of reserve samples should be sufficient to permit the Agency to perform five times all of the release tests required in the application or supplemental application. Because since at the time of releasing the guideline the FDA had limited experience with the retention and testing of non-solid oral dosage forms, the FDA was unable to recommend an upper limit for the retention of these products (including transdermal patches). Therefore I suggest keeping the five times quantity (even if this means much more than 300 samples) unless you have a scientific rationale for a less amount. The decision is in the responsibility of the sponsor.
I hope this helps.
Kind regards
Dan