Comparative bioavailability of two ramipril formulations after single-dose administration in healthy volunteers.

Author(s): Mendes GD, Dantas Sanfelice AT, do Carmo Borges NC, Cavedal LE, Sverdloff C, Prado Galuppo M, Modolo JH, De Nucci G

Affiliation(s): Department of Internal Medicine, State University of Campinas, SP, Brazil.

Publication date & source: 2006-02, Int J Clin Pharmacol Ther., 44(2):93-8.

Publication type: Randomized Controlled Trial

OBJECTIVE: To assess the bioequivalence of a ramipril 5 mg tablet formulation (ramipril test formulation from Laboratorios Biosintetica Ltda (Sao Paulo, Brazil) and Triatec from Aventis Pharma (Sueano, Brazil) standard reference formulation) in 26 healthy volunteers of both sexes. METHODS: The study was conducted using an open, randomized, 2-period crossover design with a 2-week washout interval. Plasma samples were obtained over a 36-hour period. Plasma ramipril and ramiprilat concentrations were analyzed by liquid chromatography coupled to tandem mass spectrometry (LC-MS-MS) with positive ion electrospray ionization using multiple reaction monitoring (MRM). From the ramipril and ramiprilat plasma concentration vs. time curves, the following pharmacokinetic parameters were obtained: AUClast, AUCinf and Cmax. RESULTS: The limit of quantification was 0.2 ng x ml(-1) and 1.0 ng x ml(-1) for ramipril and ramiprilat, respectively. The geometric means and 90% confidence intervals (CI) for Ramipril/Triatec and Ramiprilat/Triatec percent ratios were: 104.69% (90% CI = 93.21-117.59%) for Cmax, 102.49% (90% CI = 92.76-113.24%) for AUClast, 103.60% (90% CI = 93.56 114.73%) for AUCinf, 108.48% (90% CI = 98.86-119.03%) for Cmax, 105.88% (90% CI = 101.55-110.39%) for AUClast, 97.30% (90% CI = 90.17-104.99%) for AUCinf, respectively. CONCLUSION: Since the 90% CI for AUClast, AUCinf and Cmax ratios were within the 80-125% interval proposed by the U.S. FDA, it was concluded that the ramipril formulation produced by Laboratorios Biosintetica Ltda is bioequivalent to the Triatec formulation in both rate and extent of absorption.