Comparative bioavailability of three ibuprofen formulations in healthy human volunteers

OBJECTIVE: To assess the bioequivalence of three ibuprofen formulations (Test formulation: ibuprofen (400 mg capsule) manufactured by Cardinal Health Brasil 402 Ltda. (Sorocaba, Brazil) and licensed to Boehringer Ingelheim do Brasil Quim. e Farm. Ltda. (SA poundo Paulo, Brazil); Reference formulation (1): ibuprofen (AdvilA(R); 2 A 200 mg coated tablet) from Wyeth-Whitehall Ltda. (Itapevi, Brazil); Reference formulation (2): ibuprofen (AliviumA; 8 ml A 50 mg/ml solution) from Schering Plough S.A. (Rio de Janeiro, Brazil)) in 24 healthy volunteers of both sexes. METHODS: The study was conducted using an open, randomized, three-period crossover design with at least 5-day washout interval. Plasma samples were obtained over a 24-h period. Plasma ibuprofen concentrations were analyzed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) with negative ion electrospray ionization using multiple reaction monitoring (MRM). The following pharmacokinetic parameters were obtained from the ibuprofen plasma concentration vs. time curves: AUC(last), AUC(trunctmax), AUC(inf) and C(max). RESULTS: The limit of quantification for ibuprofen was 0.1 microg A ml(1). The geometric mean with corresponding 90% confidence interval (CI) for Test/Reference (1) percent ratios were 114.24% (90% CI = 105.67, 123.50%) for C(max), 98.97% (90% CI = 94.69, 103.44%) for AUC(last) and 99.40% (90% CI = 95.21, 103.78%) for AUC(inf). The geometric mean and respective 90% confidence interval (CI) for Test/Reference (2) percent ratios were 108.38% (90% CI = 100.19, 117.25%) for C(max), 100.79% (90% CI = 96.39, 105.40%) for AUC(last) and 101.26% (90% CI = 96.94, 105.77%) for AUC(inf); t(max) for the 400 mg Test capsule was shorter than that for the 2 A 200 mg Reference (1) tablets (p < 0.002). Conclusion: Since the 90% CI for AUC(last), AUC(inf) and Cmax ratios were within the 80 - 125% interval proposed by the US FDA, it was concluded that ibuprofen formulation manufactured by Cardinal Health Brasil 402 Ltda. and licensed to Boehringer Ingelheim do Brasil Quim. e Farm. Ltda. is bioequivalent to the AdvilA and AliviumA formulations with regard to both the rate and the extent of absorption.