Bioequivalence and Bioavailability Forum

Hi myy,

❝ A single dose, two sequence and two period- crossover bioequivalence study with 32 subjects fails to show bioequivalence because the criteria for AUC 0-t were not met (76.62-102.75%) but Cmax is clearly within the limits (81.71-109.23%). T/R of Cmax was 94.47% and T/R of AUC 0-t was 88.73%. CV% was 42.89% for Cmax and 46.99% for AUC 0-t of the test product.

The relevant CV is not for the T or R product but for the GMR. I assume that's what you meant?
Anyways, a CV for Cmax lower than CV for AUCt is quite unusual and I always question it. Please take a look at the production of data rather than just at the data.

❝ Since the test product fails to meet only the lower end of the criteria for AUC 0-t it is not truely bioinequivalent. Could it be possible that bioinequivalence was demonstrated accidentally although the two products are

actually bioequivalent? How could this be proven?

Careful with the terminology. Bioinequivalence was not shown. Your product could be BE, it has just not been demonstrated. Bioinequivalence is only if the CI is entirely outside the acceptance range.

❝ Would it be advisable to perform another bioequivalence study with the same design?

Advisable? Perhaps.
Justifiable? Yes, probably.
But you might wish to take a new look at the sample size with your max likelihood PEs and observed CVs..... after review of data production.