Bioequivalence study of two formulations of candesartan cilexetil tablet in healthy subjects under fasting conditions

INTRODUCTION The present study was conducted to compare the bioavailability of two candesartan cilexetil 16 mg tablet formulations (test and reference formulations). MATERIALS AND METHODS This study was a randomized, single- blind, two-period, cross-over study which included 24 healthy adult male and female subjects under fasting conditions. The pharmacokinetic parameters were determined based on the concentrations of candesartan (CAS 139481-59-7), using ultra-pressure high-performance liquid chromatography with a tandem mass spectrometer detector. In each of the two study periods (separated by a washout period of 1 week), a single dose of test or reference product was administered. The pharmacokinetic parameters assessed were area under the plasma concentration time curve (AUC) from time 0 hours to 24 hours, AUC from time zero to infinity, the peak plasma concentration of the drug (Cmax), time to achieve the Cmax, and the elimination half-life. RESULTS The geometric mean ratios (90% confidence interval) of the test drug/reference drug for candesartan were 100.92% (92.15%-110.52%) for the AUC from 0 hours to 24 hours, 100.24% (92.24%-108.95%) for the AUC from time zero to infinity, and 106.71% (93.20%-122.18%) for the Cmax. The differences between the test and reference product in the time to achieve Cmax values and elimination half-life values were not statistically significant (P > 0.05). The 90% confidence intervals of the test/reference AUC ratio and Cmax ratio of candesartan were within the acceptance range for bioequivalence. There was no adverse event encountered during this bioequivalence study. CONCLUSION It was concluded that the two candesartan tablet formulations (the test and reference product) were bioequivalent.