In vitro activity of CP-74,667. A new fluoroquinolone compared with other quinolones.
CP-74,667, a 6-fluoro-7-bridged piperazinyl-1-cyclopropyl-4 quinolone, inhibited 90% of staphylococci, beta-hemolytic streptococci, enterococci, Enterobacteriaceae, and Pseudomonas aeruginosa at less than or equal to 2 micrograms/ml. Ciprofloxacin-resistant, methicillin-resistant Staphylococcus aureus had minimum inhibitory concentration (MIC50) of 4 micrograms/ml and an MIC90 of 8 micrograms/ml. CP-74,667 was fourfold more active than ciprofloxacin against Streptococcus pneumoniae and St. pyogenes, but equal or less active than tosufloxacin against Gram-positive species. The MIC90 for P. aeruginosa was 5 micrograms/ml similar to temafloxacin. The CP-74,667 MIC90 for Bacteroides fragilis was 2 micrograms/ml, equal to tosufloxacin and temafloxacin. Activity was eight- to 16-fold less at pH 5.5 compared with pH 7.4 and also eight- to 16-fold less in urine. Magnesium ions markedly increased the CP-74,667 minimum bactericidal concentrations (MBCs). The development of resistance to CP-74,667 was similar to that found for other fluoroquinolones.
Gu
J W
JW
Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY 10032.
Fang
W
W
Chin
N X
NX
Neu
H C
HC
D000890:Anti-Infective Agents / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects*; D002939:Ciprofloxacin / Q000494:pharmacology; D004352:Drug Resistance, Microbial; D024841:Fluoroquinolones; D006801:Humans; D008826:Microbial Sensitivity Tests; D009287:Naphthyridines / Q000494:pharmacology; D015363:Quinolones / Q000494:pharmacology*
D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D009287:Naphthyridines; D015363:Quinolones; C054745:temafloxacin; D002939:Ciprofloxacin; C077152:7-(8'-methyl-3',8'-diazabicyclo(3.2.1)oct-3'-yl)-1-cyclopropyl-6- fluoro-1,4-dihydro-4-oxo-3-quinolinecarboxylic acid; C055185:tosufloxacin