Journal of Bioequivalence & Bioavailability

Importance of metabolite data in bioequivalence studies: Sample size and power

5^th World Congress on Bioavailability and Bioequivalence Pharmaceutical R&D Summit

September 29-October 01, 2014 DoubleTree by Hilton Baltimore-BWI Airport, USA

Lara Tutunji and Maha Tutunji

Accepted Abstracts: J Bioequiv Availab

Abstract:

Purpose: To calculate the sample size and power for the parent compound, the metabolite, and the sum of the parent compound and metabolite in order to determine the role of the metabolite in the decisions made in bioequivalence studies Methods: Data presented were obtained from several bioequivalence studies under fasting conditions for drugs that have active metabolites. The analytical method used was a validated LC-MS/MS method. Bioequivalence criteria of 80-125 % were applied to the parent compound, the active metabolite, and the sum of the parent drug and the active metabolite. Pharmacokinetic data mainly AUC, Tmax, Cmax, and elimination half-life were reported. Results: Similar results were obtained for the parent drug, metabolite, and the sum of the parent drug and metabolite for AUC. In the case of Cmax, the intersubject variability for the metabolite and the sum of the parent and the metabolite was lower than that of the parent drug while the power of the bioequivalence decision was higher for the metabolite and the sum of the parent drug and the metabolite. Conclusions: The power of estimating Cmax using the metabolite data was higher than for the drug alone so a more accurate decision can be made using the metabolite data. As a result of the higher power, the sample size can be lowered accordingly