Comparative bioavailability of ciprofloxacin tablets

Abstract

Four brands of ciprofloxacin film-coated tablets were evaluated. In vitro studies indicated that all brands met the requirements of the British Pharmacopoeia 1988 and the United States Pharmacopoeia XXII for disintegration times and dissolution test, respectively. However, brand D disintegrated significantly slower than the innovator’s product did meanwhile dissolution rates of all brands were about the same. The comparative bioavailability of ciprofloxacin tablets were determined using crossover study in 12 healthy male volunteers. After receiving a single oral dose of 250 mg ciprofloxacin tablet, blood samples were collected at predetermined time intervals and they were analyzed employing the HPLC. Data analysis by CSTRIP computer program demonstrated that there were no statistically significant differences for the relevant pharmacokinetic parameters (Cmax, tmax and AUC) among the four brands (P > 0.05). This referred that all brands were bioequivalent in terms of both the rate and the extent of drug absorption. The relative bioavailability of brands B, C, and D with respect to the innovator’s product (brand A) were 95.92, 105.82 and 108.07%, respectively. No statistical correlation between the in vitro and the in vivo data were observed. The pharmacokinetic of ciprofloxacin following oral administration of 250 mg tablet was well described by mean of a two-compartment open model with first order absorption and elimination and no lag time. The absorption rate constants ranged from 2.20-3.04 hr. The peak plasma concentrations were from 1.86-2.13 mcg/ml established within 0.96-1.20 hr, and the biological half life was about 3.55-3.81 hr.