Bioequivalence of memantine hydrochloride tablets in healthy volunteers

Objective:To evaluate the bioequivalence oi memantine hydrochloride test and reference preparations in healthy volunteers.Methods:Twenty-four healthy male volunteers were randomly administered with an oral single dose of 10 mg test or reference memantine hydrochloride tablets in an open-label,2-period crossover study with a 28 d washout period.The blood samples were collected at the scheduled time before and after administration.The plasma concentrations of memantine were determined by LC-MS/MS method.The pharmacokinetic parameters tmax,cmax,AUC0-t,AUC0-∞,MRT and t1/2 were calculated by non compartmental model method.Results:The main pharmacokinetic parameters of the test and reference memantine hydrochloride preparations were as follows:tmax（8.29±4.7） and（9.04±4.2） h;cmax（13.3±1.82） and（12.1±1.66） ng/ml;AUC0∞（1140±200） and（1080±224） ng · h · ml-1;t1/2（60.2±11.4） and（59.1 ± 12.6） h,respectively.The relative bioavailability of the test preparations was（107.1±12.6）%.Ninety percent confidence intervals(CD of both the geometric mean value ratios of AUC0-t and cmax were 80%-125%.Conclusion:Memantine hydrochloride test and reference preparations have bioequivalence.