Temafloxacin: in vitro comparison with five other antibacterial agents

The in vitro activity of the new fluorinated quinolone temafloxacin was compared with the activities of ciprofloxacin, fleroxacin, ofloxacin, ceftazidime and tobramycin. A total of 662 recent clinical isolates were included in the study, representing a variety of gram-negative and gram-positive bacteria. An agar dilution method was employed for the determination of minimal inhibitory concentrations (MICs). Ciprofloxacin showed the highest potency against the Enterobacteriaceae, 90% of the isolates being inhibited by 0.06 mg/l or less. The other quinolones were also highly active (MIC90 = 0.25-0.5 mg/l). Ciprofloxacin and tobramycin were the most active agents against the Pseudomonas isolates (MIC90 = 0.25 and 0.5 mg/l, respectively), whereas the activities of temafloxacin, fleroxacin and ofloxacin were more variable. All the quinolones had relatively high and similar activity against Staphylococcus aureus and S. epidermidis, but S. saprophyticus was markedly less susceptible to fleroxacin than to the other quinolones. The activity of temafloxacin against Streptococcus pneumoniae was somewhat higher than those of the other quinolones tested. Temafloxacin showed variable activity against Bacteroides fragilis isolates but was generally more potent against these isolates than were the other quinolones. The MICs of temafloxacin were slightly lower at pH 7.3 compared with those obtained at pHs 5.8 or 8.8.