Bioequivalence study of two tablet formulations containing rimonabant 20 mg in healthy Indian subjects

Abstract

A randomized, two-treatment and two-way crossover study on twelve healthy Indian male subjects was conducted to assess the bioequivalence of two tablet formulations containing 20 mg of rimonabant (CAS 158681-13-1). Both of the formulations were administered orally as a single dose with a 45-day washout period between two dosing sessions. The content of rimonabant in plasma was determined by a validated HPLC method with UV detection. The formulations were compared using the parameters area under the plasma concentration-time curve (AUC_0−t), area under the plasma concentration-time curve from zero to infinity (AUC_0−∞), peak plasma concentration (C_max), and time to reach peak plasma concentration (t_max). The results of this investigation indicated that there were no statistically significant differences between the logarithmically transformed AUC_0−∞ and C_max values of the two preparations. The 90% confidence interval for the ratio of the logarithmically transformed AUC_0−t, AUC_0−∞ and C_max were within the bioequivalence limit of 0.8-1.25 and the relative bioavailability of the test formulation was 96.62% of that of the reference formulation. Thus, these findings clearly indicate that the two formulations are bioequivalent in terms of rate and extent of drug absorption.

Key words

Anti-obesity drug - Bioequivalence - CAS 158681-13-1 - HPLC - Pharmacokinetics - Rimonabant

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