Back Calculating Sample Size [Power / Sample Size]

posted by Sereng  – USA, 2022-05-12 19:40 (799 d 04:23 ago) – Posting: # 22977
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Dear colleagues, if you have data from a completed BE study where the upper bound of the 90% CI of Cmax was outside the acceptance range, is it possible to calculate a new sample size that would likely meet the BE requirements (or declare futility)? In this case, the following are details of the completed BE study, where the reference drug Cmax had almost twice the CV of the Test drug.

Parallel Group Design
Two Groups (n=70/group)
Cmax (Ref): 478 +/- 434 (mean +/- SD)
Cmax (Test): 489 +/- 909 (mean +/- SD)
Ratio (90% CI): 109.00 (87.00-135.00)


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