Apixaban Pharmacokinetics and Bioequivalence of Two Tablet Formulations: A Randomized, Open-Label, Crossover Study, Fasting Condition in Healthy Indonesian Volunteers.

The present study aimed to assess the bioequivalence of a new apixaban generic with reference formulation. Twenty-six healthy volunteers were recruited for an open-label, balanced, randomized, 2-treatment, 2-sequence, 2-period, single oral dose study. Following overnight fasting, each volunteer received 5 mg of apixaban test and reference formulations as single doses, separated by a 1-week washout period. Twenty blood samples were collected at predose and multiple time points between 0.5 and 72 hours after dosing. A validated ultra-performance liquid chromatography-tandem mass spectrometry detection method following a protein precipitation step was implemented to determine apixaban concentrations. Noncompartmental analysis was used to derive the pharmacokinetic parameters, which were then compared between the test and reference products using a multivariate analysis of variance. The pharmacokinetic parameters of the test product were not statistically different from the reference product, and the 90% confidence intervals of apixaban natural log-transformed area under the concentration-time curve from time 0 to infinity, area under the concentration-time curve from time 0 to the last measurable concentration, and maximum concentration were within 80%-125% based on the bioequivalence acceptance range criteria. The test and reference formulations of apixaban are bioequivalent in healthy subjects under fasting conditions.

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.