Bioequivalence and Bioavailability Forum

Hy yourself,

❝ Sponsor wants to make a little cheaper by having only 24 h sampling in the pilot, but considerably longer in the pivotal trial.

❝

❝ Good idea? Regarding sample size estimation for the pivotal (including adjusted acceptance range for Cmax, but standard acceptance range for AUC...).

That's likely going to be fine. It will regularly be Cmax that is the showstopper. Even if your AUC does not cover 80% and if you are not sampling to 72hrs, then the idea you get about AUC aspects will still be very qualified.

Note one thing which is commonly misunderstood: When pilot trials have small sample sizes compared to pivotal studies (which is almost a definition) then they do not give good info about formulation matches in BE (or, where applicable, of superiority prospects, but this is often very dependent of placebo arms).
Pilot BE studies are great for everything but screening for formulation matches.