Studies on the bioequivalence of second generation cephalosporins: cefaclor capsules and suspension

The aim of the present studies, performed in two different groups of volunteers, was to prove the bioequivalence of 500 mg cefaclor (CAS 70356-03-5) test and reference capsules (Losefar 500 mg Capsules as test and an originator product as reference; study 1) and cefaclor 250 mg/5 mL test and reference suspensions (Losefar 250 mg/5 mL Granules oral suspension as test and an originator product as reference; study 2). Each study was conducted according to an open, randomized, single-dose, two-period cross-over design in healthy volunteers with a wash-out period from 7 to 14 days. Blood samples were taken up to 8 h post dosing, and concentrations of cefaclor were determined by HPLC method. In the first study, the 90% confidence intervals for intra-individual ratios of AUC0-t and Cmax of cefaclor were 0.99-1.08 for AUC0-t and 0.82-1.06 for Cmax, and thus within the acceptance ranges for bioequivalence trials. The 90% confidence interval for intra-individual ratios of AUC0-t and Cmax of cefaclor administered as suspensions were 1.10-1.19 and 1.02-1.21, respectively. These values were also within the acceptance range. Concerning the secondary parameter tmax the 90% confidence interval for the intra-individual differences for cefaclor were between -0.13 - 0.13 in the first and between 0.00 - 0.13 in the second study, respectively. In the light of the results of the studies reported here it can be concluded that cefaclor test formulations, i.e. capsules and suspension are bioequivalent to the respective reference formulations.