Model simulation of a single oral dose of cefuroxime axetil and the related in-vitro kill kinetics against four bacterial species.

An in-vitro model was shown to be capable of simulating a cefuroxime serum profile equivalent to that observed in human volunteer studies, following a single dose of 250 mg cefuroxime axetil. The model was used to carry out kill kinetic studies and showed cefuroxime to lyse the four bacterial test strains, time of onset of lysis being related to the sensitivity of the respective organisms. The more sensitive Staphylococcus aureus and Haemophilus influenzae strains were subject to a higher absolute kill and showed no regrowth over the duration of the simulated serum profile. In contrast, Proteus mirabilis and Escherichia coli showed regrowth after 4 and 5 h respectively. The kill kinetic profiles of the respective organisms are discussed in relation to the pharmacokinetic analysis of the cefuroxime serum profile.