Bioequivalence study of two esomeprazole enteric coated formulations in healthy Chinese volunteers

A bioequivalence study of two esomeprazole (CAS 119141-88-7) enteric-coated formulations was carried out in 20 healthy Chinese volunteers according to a single dose, two-sequence, crossover randomized design. The two formulations were administered in two treatment days, separated by a washout period of 7 days. Blood samples were collected at specified time intervals over 10 h post-dosing. Plasma samples were separated and assayed for esomeprazole using a selective and sensitive HPLC method with UV detection. The pharmacoldnetic parameters AUC(0-12h), AUC(max), C(max), t(max), t(1/2) and MRT were determined from the plasma concentration-time profile of both formulations. ANOVA and two one-sided t-test procedures showed no significant difference in log-transformed AUC(0-12h) and AUC(0-infinity) while the 90% confidence interval (CI) of the ratio of the geometric means of their values were also used to assess bioequivalence between the two formulations. The results of this study indicated that the two esomeprazole formulations can be considered to be bioequivalent.