In vitro and in vivo evaluations of A-80556, a new fluoroquinolone.

Abstract

A-80556 is a novel fluoroquinolone with potent antibacterial activity against gram-positive, gram-negative, and anaerobic organisms. A-80556 was more active than ciprofloxacin, ofloxacin, lomefloxacin, and sparfloxacin against gram-positive bacteria. A-80556 was particularly active against Staphylococcus aureus (MIC for 90% of isolates [MIC90], 0.12 microgram/ml, relative to fluoroquinolone-susceptible strains) and Streptococcus pneumoniae (MIC90, 0.12 microgram/ml). A-80556 was also the most active of the quinolones tested against ciprofloxacin-resistant S. aureus, with an MIC90 of 4.0 micrograms/ml; that of ciprofloxacin was > 128 micrograms/ml. However, the significance of this activity is not known. A-80556 was slightly less active against Escherichia coli (MIC90, 0.06 microgram/ml) and other enteric organisms than ciprofloxacin (MIC90 for E. coli, < or = 0.03 microgram/ml). A-80556 was slightly less active against Pseudomonas aeruginosa (MIC90, 4.0 micrograms/ml) than ciprofloxacin (MIC90, 2.0 micrograms/ml) and more active against Acinetobacter spp. (respective MIC90s, 0.12 and 0.5 microgram/ml). A-80556 was also the most active compound against anaerobes. Against Bacteroides fragilis, the MIC90 of A-80556 was 2.0 micrograms/ml; that of ciprofloxacin was 16 micrograms/ml. The in vivo efficacy of A-80556 in experimental models with both gram-positive and gram-negative infections was consistent with the in vitro activity and pharmacokinetics and oral absorption in mice.

• Authors: J J Clement, S K Tanaka, J Alder, C Vojtko, J Beyer, D Hensey, N Ramer, D McDaniel, D T Chu
• Journal: Antimicrobial agents and chemotherapy (Antimicrob Agents Chemother) Vol. 38 Issue 5 Pg. 1071-8 (May 1994) ISSN: 0066-4804 [Print] United States
• PMID: 8067740 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Anti-Infective Agents
• Fluoroquinolones
• Quinolones
• A 80556

Topics

• Animals
• Anti-Infective Agents (pharmacokinetics, pharmacology, therapeutic use)
• Bacteria (drug effects)
• Bacteria, Anaerobic (drug effects)
• Bacterial Infections (drug therapy, microbiology)
• Drug Resistance, Microbial
• Female
• Fluoroquinolones
• Gram-Negative Bacteria (drug effects)
• Gram-Positive Bacteria (drug effects)
• Mice
• Mice, Inbred Strains
• Microbial Sensitivity Tests
• Quinolones (pharmacokinetics, pharmacology, therapeutic use)