Bioequivalence study of two pharmaceutical forms of rifampicin capsules in man

In this study the bioavailability of a new pharmaceutical form of rifampicin, Rifampicine Generic (300 mg capsules), was compared to a reference form Rimactan (300 mg capsules). Twelve healthy volunteers participated in a cross-over study. Each dosage form was administered, one after the other, to each subject in the morning after a fasted night period. Both forms were well tolerated and no side effects were observed in any of the subjects during the study. Blood samples were collected over 10 h. The rifampicin plasma concentrations were determined by an HPLC method. The pharmacokinetic parameters, Cmax, Tmax, AUC0-10h (mean +/- SD), were 6.06 +/- 2.95 micrograms/ml, 2.33 +/- 1.60 h, 25.57 +/- 12.6 micrograms.h.ml-1, respectively, for the new form and 6.55 +/- 2.47 micrograms/ml, 2.04 +/- 1.37 h, 26.11 +/- 9.10 micrograms.h.ml-1, respectively, for the reference form. The statistical analysis of different parameters with the Westlake method, ANOVA, and the Wilcoxon test with a probability of 95% showed no differences between the two forms of rifampicin. It was concluded that Rifampicine Generic 300 mg capsules are bioequivalent to Rimactan 300 mg capsules.