In vitro comparison of A-56619, A-56620, amifloxacin, ciprofloxacin, enoxacin, norfloxacin, and ofloxacin against methicillin-resistant Staphylococcus aureus

Abstract

Seven quinolone antibiotics were tested against 115 isolates of methicillin-resistant Staphylococcus aureus. The MICs for 90% of the strains tested were 0.5 microgram/ml for A-56619, A-56620, ciprofloxacin, and ofloxacin; 2.0 micrograms/ml for amifloxacin and enoxacin; and 4.0 micrograms/ml for norfloxacin. Killing kinetic studies showed a similar killing rate for all seven antibiotics.