Bioequivalence review for drug interchangeability.

To monitor the performance of the approved generic copies of a brand-name drug, we propose some methods in assessing bioequivalence among generic copies and the brand-name drug, and among generic copies themselves, using data from several bioequivalence studies adopting the standard 2 x 2 crossover design without carryover effects. We propose a meta-analysis method that increases statistical power when the between-subject variability is not large. A nonmeta-analysis is also considered. A numerical example of applying both methods is presented for illustration.