Evaluation of the bioequivalence of capsules containing 150 mg of fluconazole

Fluconazole is an antifungal agent. The purpose of this study was to evaluate bioequivalence of two commercial 150 mg capsule formulations of fluconazole available in the Brazilian market. The study was an open, randomized, two-period, two-group crossover trial with a 2-week washout interval. Blood samples were collected throughout a 96-h period after administration of reference product (R) and test product (T) to 28 fasting volunteers. A simple, accurate, precise and sensitive high-performance liquid chromatographic (HPLC) method with ultraviolet detection was developed and validated for quantification of fluconazole in plasma samples after liquid-liquid extraction. Bioequivalence between the products was determined by calculating 90% confidence intervals (90% C.I.) for the ratio of Cmax, AUC0−t and AUC0−∞ values for the test and reference products, using logarithmic transformed data. The 90% confidence intervals for the ratio of Cmax (101.06-105.45%), AUC0−t (97.11-104.69%) and AUC0−∞ (97.96-103.36%) values for the test and reference products are within the 80-125% interval, proposed by FDA and EMEA. It was concluded that the two fluconazole formulations are bioequivalent in their rate and extent of absorption.