Relative bio-availability of sultamicillin in healthy volunteers following administration of two tablet formulations.

The pharmacokinetics of both ampicillin and sulbactam obtained from a balanced, open two-way crossover study in 20 normal adult volunteers receiving a single 375 mg oral tablet of sultamicillin administered as two different formulations--the original product (Duocid) and a generic formulation that is commercially available in Turkey--were compared. Pharmacokinetic parameters for the two formulations and for both ampicillin and sulbactam were tested for bio-equivalence by the two one-sided Student's t-test (80-120% range; P < 0.1). Area under concentration--time curves and maximum concentrations for both components were found to be non-equivalent for the two formulations, the generic formulation having consistently lower mean values. The results were consistent with studies of the in vitro release of sultamicillin from the two tablets. It is concluded that the generic formulation is pharmacokinetically inferior to the original product.