Susceptibility and bactericidal activity of 8 oral quinolones against conventional-fluoroquinolone-resistant Streptococcus pneumoniae clinical isolates.

We evaluated the pharmacokinetic/pharmacodynamic parameters of 8 oral quinolones (ciprofloxacin, garenoxacin [GRNX], gatifloxacin, levofloxacin, moxifloxacin, prulifloxacin, sitafloxacin, and sparfloxacin) on 11 fluoroquinolone-resistant Streptococcus pneumoniae strains, screened from 780 strains isolated from various clinical sources in Japan. GRNX showed the highest area under the blood concentration time curve/MIC ratios, which exceeded the target values for bacterial eradication against all fluoroquinolone-resistant S. pneumoniae strains.