title: Relative bioavailability study of 20-mg enalapril tablets in healthy male volunteers.
abstract: The pharmacokinetic and relative bioavailability studies of 20-mg enalapril tablets, the test product manufactured by Biolab, Thailand compared to the reference product (Merck Sharp & Dohme, USA) was conducted in 14 healthy Thai male volunteers following a single dose, two-period, crossover design. Each subject received 20-mg enalapril tablets of both formulations with a 1-week washout period. Plasma samples collected over a 24-h period after administration were analyzed by LC/MS/MS. Pharmacokinetic parameters were determined by using non-compartmental analysis. Regarding bioequivalence testing, the 90 per cent confidence intervals of Cmax and AUC(0-infinity) ratios (test/reference) of enalapril were 101.8-134.9 per cent and 105.9-121.4 per cent and those of enalaprilat were 104.2-122.3 per cent and 104.5-118.1 per cent. Based on the European bioequivalence guideline, the 90 per cent confidence intervals of Cmax and AUC(0-infinity) ratios of both parent and metabolite forms were within the acceptable ranges of 70-143 per cent and 80-125 per cent, respectively. It was concluded that the test formulation was bioequivalent to the reference formulation and both formulations can be used interchangeably in clinical practice.
authors.affiliation: Bioequivalence Test Center, Faculty of Pharmaceutical Sciences, Naresuan University, Phitsanulok 65000, Thailand.
authors.forename: Ornrat
authors.initials: O
authors.lastname: Lohitnavy
authors.forename: Manupat
authors.initials: M
authors.lastname: Lohitnavy
authors.forename: Sanglar
authors.initials: S
authors.lastname: Polnok
authors.forename: Prawit
authors.initials: P
authors.lastname: Taytiwat
mesh_terms: D000293:Adolescent; D000328:Adult; D000959:Antihypertensive Agents / Q000493:pharmacokinetics*; D001682:Biological Availability; D018592:Cross-Over Studies; D004656:Enalapril / Q000493:pharmacokinetics*; D015773:Enalaprilat / Q000493:pharmacokinetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D014838:Volunteers
chemical_list: D000959:Antihypertensive Agents; D004656:Enalapril; D015773:Enalaprilat