ABSTRACT
As indicated in Chapter 1, one of the major objectives of a bioavailability and bioequivalence study comparing two formulations (e.g., a test formulation and a reference formulation) of a drug product is to determine whether the two formulations are average bioequivalent. During the planning stage of a bioavailability and bioequivalence study, the following questions concerning the study sample size are of particular interest to the clinicians:
1. How many subjects are needed to have a desired power (e.g., 80%) establishing average bioequivalence between two formulations within clinically important limits (e.g., 20% of the reference mean)?
