In vitro antibacterial activity of fleroxacin

Abstract

In vitro activity of fleroxacin against Gram-positive and-negative bacteria was determined. Fleroxacin showed potent activity against most enterobacteriaceae, Neisseria spp., and Haemophilus influenzae and good activity against staphylococci, Pseudomonas aeruginosa, and Branhamella catarrhalis. Against these bacteria, its activity was roughly comparable to that of norfloxacin and ofloxacin, but slightly less than that of ciprofloxacin. It also showed good activity against methicillin-resistant Staphylococcus aureus and gentamicin-resistant P. aeruginosa. Neither the medium, variation in medium pH, inoculum size, nor the addition of cations or human serum, had any major effect on its activity. It was bactericidal at concentrations around the MIC. It also strongly inhibited the supercoiling activity of DNA gyrase purified from Escherichia coli and P. aeruginosa. Fleroxacin produced an excellent postantibiotic effect (PAE) against E. coli, P. aeruginosa and S. aureus. © 1990, Japanese Society of Chemotherapy. All rights reserved.