Bioequivalence Studies and Highly Variable Drugs: Things to Consider – BIO1. Highly-variable drugs (HVD) are the drugs whose within-subject variance is larger than 30% (1). In other words, most of the drugs have a predictable pharmacokinetic profile within a subject, but there are drugs whose pharmacokinetic profile may differ from one use ...
The approach of scaled bioequivalence is enormously advantageous: it decreased the number of required subjects and allowed testing highly variable drugs. In principle, both the FDA and EMA have similar approaches to scaling bioequivalence, but the differences favour the approach suggested by EMA.