Comparison of pharmacokinetics of sitagliptin 100 mg tablets in healthy Asian Indian and Thai volunteers.

OBJECTIVE: The purpose of this study was to compare the Pharmacokinetics of Sitagliptin 100 mg tablets in healthy Asian Indian and Thai Volunteers. MATERIALS AND METHODS: Two independent crossover evaluations were conducted in healthy adults of Indian (Study 1) and Thai (Study 2) origin. Participants received a single 100 mg dose of either test or reference sitagliptin tablet under fasting conditions, followed by the alternate product after a washout. Plasma sitagliptin was quantified by validated LC-MS/MS, and non-compartmental analysis yielded Cmax, AUC0-t, AUC0-∞, and Tmax. Bioequivalence was concluded when 90% confidence intervals (CIs) for geometric mean ratios fell within 80%-125%. RESULTS: For both Indian and Thai cohorts, point estimates and 90% CIs for Cmax, AUC0-t and AUC0-∞ were contained in predefined 80%-125% interval, and no clinically meaningful differences between formulations were detected. Exposure metrics were comparable across the two ethnic groups. CONCLUSIONS: In the two studies conducted in healthy Asian Indian and Thai volunteers, the test and reference formulation of sitagliptin 100 mg exhibited comparable pharmacokinetics profiles and were bioequivalent according to the regulatory definition based on rate and extent of absorption. Both formulations were well tolerated by all volunteers. Similar Cmax and AUC values were observed across both populations, indicating that ethnicity has no significant effect on the pharmacokinetics of sitagliptin. Therefore, bioequivalence results obtained in one population can be extrapolated to others.