Bioequivalence and Bioavailability Forum

Question guys...

Does FDA (or EMA) really care about the power of a study? Example, hypothetically speaking, lets say I set up a study with a sample size of xx (yes n>12) based on a power of 70% and the study passes. Does it matter that my power is less than 80%?

Why do I ask? My recent pilot study (3-way partial rep, n=60, withinsubject CV of ref = 55-60%) ended up with a (Highest) ratio of 1.2 and 95% upper confidence limit of -0.12456 ⇒ Tada, it passed BE.

We will proceed with a pivotal study, the formulation will be identical with no potential variabilities (So if there is then it's not my fault!). If I follow Endrenyi et al's paper on sample size for HVD then I will be looking at n~200 subjects for a 3-way partial replicate study at 80% power. For a 4-way full replicate study at 80% power, n~120. Management said no go. For a compromise I think we should be able to go with n=80. Based on R, with a ratio=1.2 & CV=0.6, the power will be ~70%. I think we are good to go but I am curious if the agency would care about this power business...

Any comment?

Thanks
John

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Edit: Category changed. [Helmut]