Objective: To compare the bioavailability of two cefadroxil capsule (500 mg) formulations (Cefadroxila from Eurofarma Laboratórios Ltd, Brazil, as test formulation and Cefamox from Bristol-Myers Squibb, Brazil S.A. as reference formulation) in 24 volunteers of both sexes.
Material and methods: The study was conducted open with randomized two-period crossover design and a 1-week washout period. Plasma samples were obtained over a 12-h interval. Cefadroxil concentrations were analysed by combined reversed-phase liquid chromatography and tandem mass spectrometry (LC-MS-MS) with positive ion electrospray ionization using a selected ion monitoring method. From the cefadroxil plasma concentration versus time curves the following pharmacokinetic parameters were obtained: AUC(last), AUC(0-infinity) and C(max).
Results: Geometric mean of Cefadroxila/Cefamox 500 mg individual percent ratio was 103.97% for AUC(last), 104.08% for AUC(0-infinity) and 95.23% for C(max). The 90% confidence intervals (CI) were 98.14-110.16%, 98.37-110.12%, and 85.59-105.96%, respectively.
Conclusion: Since the 90% CI for C(max), AUC(last) and AUC(0-infinity) were within the 80-125% interval proposed by the Food and Drug Administration, it was concluded that the Cefadroxila 500 mg capsule was bioequivalent to the Cefamox 500 mg capsule, according to both the rate and extent of absorption.
Copyright 2000 John Wiley & Sons, Ltd.