Bioequivalence evaluation of two brands of ketoconazole tablets (Onofin‐K ® and Nizoral ® ) in a healthy female Mexican population

A randomized, crossover study was conducted in 24 healthy female volunteers to compare the bioavailability of two brands of ketoconazole (200 mg) tablets; Onofin‐K ® (Farmacéuticos Rayere S.A., México) as the test and NIZORAL ® (Janssen‐Cilag, México) as the reference products. The study was performed at the Clinical Pharmacology Research Center of the Hospital General de México in Mexico City. Two tablets (400 mg) were administered as a single dose with 250 ml of water after a 12 h overnight fast on two treatment days separated by a 1 week washout period. After dosing, serial blood samples were collected for a period of 12 h. Plasma harvested was analysed for ketoconazole by a modified and validated HPLC method with UV detection in the range 400–14000 ng/ml, using 200 µl of plasma in a full‐run time of 2.5 min. The pharmacokinetic parameters AUC 0−t , AUC 0−α , C max , T max and t 1/2 were determined from plasma concentrations of both formulations and the results discussed. AUC 0−t , AUC 0−α and C max were tested for bioequivalence after log transformation of data, and no significant differences were found either in 90% classic confidence interval or in the Anderson and Hauck test ( p <0.05). Based on statistical analysis, it is concluded that Onofin‐K ® is bioequivalent to Nizoral ® . Copyright © 2004 John Wiley & Sons, Ltd.