Evaluation of the pharmacokinetics and absolute bioavailability of three isosorbide-5-mononitrate preparations in healthy volunteers.

The objective of this study was two-fold: 1. to determine the pharmacokinetic parameters and the bioavailability of two 20 mg isosorbide-5-mononitrate (CAS 16051-77-7, IS-5-MN) preparations (treatments A and B) after single oral administration and 2. to evaluate the absolute bioavailability of IS-5-MN, which was possible by the administration of a third IS-5-MN preparation (treatment C) by the intravenous route (1 mg/ml, dose 20 mg). The three preparations were examined in 24 healthy volunteers according to a randomized 3-way cross-over design, blood samples were withdrawn up to 24 h following the administration of IS-5-MN and plasma concentrations of IS-5-MN were quantified by a gas chromatography method. The two oral preparations led to peak concentration values of about 360 ng/ml of IS-5-MN in the mean 0.90 h (treatment A) and 0.97 h (treatment B) after drug administration. The corresponding values for the infusion were 339.6 ng/ml and 2.59 h in the mean. For the areas under the curve (AUC(0-infinity)) mean values of 2733 (treatment A). 2724 (treatment B) and 2877 h x ng/ml (treatment C) were found. The absolute bioavailability of both oral treatments revealed values of 95.00% and 94.74% for treatments A and B, respectively. The statistical comparison (ANOVA, confidence intervals) of the pharmacokinetic parameters showed bioequivalence between both oral preparations and equivalence in the amount of drug absorption between both oral formulations and the i.v.-infusion. The observed undesired side effects (e.g. headache or nausea) are well known to occur after IS-5-MN administration.

RCT Entities:   Population Interventions Outcomes