Bioequivalence of clopidogrel hydrogen sulfate tablets in healthy Chinese volunteers.

We aimed to evaluate the bioequivalence of clopidogrel in healthy Chinese volunteers after administration of a single oral dose. We administered a single oral dose of 75 mg clopidogrel (test and reference) to 32 healthy Chinese volunteers according to an open, randomized, crossover design. The concentration of clopidogrel acid (carboxylic metabolite of clopidogrel) in the plasma was determined using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Bioequivalence of the test and reference preparations were calculated using analysis of variance and one-sided t-test by using the DAS 2.0 software. The pharmacokinetic parameters of the test and reference preparations were as follows: peak plasma concentration (Cmax), 1351.101 ± 654.955 ng/mL and 1184.652 ± 607.713 ng/mL; area under the curve, 2642.017 ± 1093.848 ng·h/mL and 2780.666 ± 1283.100 ng·h/mL; and time to reach Cmax (Tmax), 0.789 ± 0.318 h and 0.953 ± 0.633 h, respectively. The relative bioavailability of the formulation was 101.7 ± 35.3%, which indicated that the test preparation was bioequivalent to the reference drug.

Effect of CYP2C9*3 mutant variants on meloxicam pharmacokinetics in a healthy Chinese population.

The aim of this study was to investigate the effect of the CYP2C9*3 (CYP2C9 1075 A>C) polymorphism on meloxicam pharmacokinetics in a Chinese population. Twenty-four healthy volunteers were enrolled in this study. The pyrosequencing technique was used to identify polymorphisms of CYP2C9. The concentration of meloxicam in plasma was determined by a high-performance liquid chromatography assay with mass spectrographic analysis. The Drug and Statistics Software (DAS, version 2.0) was used for curve fitting and calculations of pharmacokinetic parameters. The effects of CYP2C9*3 variant genotypes on meloxicam pharmacokinetics were compared with those of the wild type genotype. Among the 24 volunteers, two AC heterozygotes were observed in the multi-dose group. CYP2C9*3 was found to play an important role in the metabolism of meloxicam by reducing its enzymatic activity. Therefore, results of this study provide helpful information regarding inter-individual pharmacokinetic variability in the Chinese population.