Bioequivalence of two oral formulations of gatifloxacin tablets in healthy male volunteers.

Objective: The purpose of this randomized, crossover study was to compare the bioavailability of a generic and innovator formulation of gatifloxacin 400 mg tablets under fasting conditions.Methods: Seventeen blood samples per period were collected from 24 healthy, Arab male volunteers over 36 hours, plasma gatifloxacin concentrations were determined by HPLC assay, and pharmacokinetic parameters were deter-mined by the non-compartmental method.Results: Mean +/- SD C[max], T[max], AUC[for symbol see text] AUC[for symbol see t4st], and t[1/2]] were 4.88 +/- 1.02 and 4.88 +/- 0.99 microg/mL, 1.19 +/- 0.62 and 1.14 +/- 0.79h, 37.81 +/- 5.54 and 39.12 +/- 5.19 microg.h/mL, 39.68 +/- 5.86 and 38.00 +/- 5.43 microg.h/mL, and 8.07 +/- 0.62 and 8.08 +/- 0.75 h for the generic and innovator formulation, respectively. ANOVA revealed significant formulation effect for AUC[for symbol see text] and AUC[for symbol see text]. However, the parametric 90% confidence intervals on the mean of the difference between log-transformed values were within the bioequivalence accepted range of 80 to 125%, namely: 102.06% to 107.34%,101.69% to 107.10%, and 94.00% to 106.10%, for AUC [for symbol see text], AUC [for symbol see text], and C[max], respectively.Conclusion: The results indicate that the two formulations are both statistically different and equivalent, in the rate and extent of absorption. This may be due to a large sample size in relation to sample variance. [ABSTRACT FROM AUTHOR]