Lomefloxacin: microbiologic assessment and unique properties.

In comparative studies, lomefloxacin, a new difluorinated quinolone, exhibits broad antibacterial activity in vitro, similar or superior to that of other quinolones (enoxacin, ofloxacin, pipemidic acid, nalidixic acid, and norfloxacin) but less than that of ciprofloxacin. Lomefloxacin inhibited Neisseria gonorrhoeae, Moraxella (Branhamella) catarrhalis, Haemophilus influenzae, Pseudomonas aeruginosa, Staphylococcus aureus, and the majority of aerobic gram-negative rods, including nosocomial isolates, at concentrations readily achievable in biologic fluids and tissues. Lomefloxacin was less active against obligate anaerobes and streptococci. Organisms resistant to methicillin, penicillin, or the aminoglycosides were susceptible to lomefloxacin. No significant lomefloxacin resistance was identified in 18 countries in which in vitro studies were conducted, with the exception of a small number of strains tested in France. The frequency with which spontaneous single-step resistance to lomefloxacin develops in vitro is low.