SUSCEPTIBILITY OF PENICILLIN-SUSCEPTIBLE AND PENICILLIN-RESISTANT PNEUMOCOCCI TO CFC-222, A NEW FLUOROQUINOLONE

The in-vitro activity of 12 antibacterial agents against 98 clinical i solates of Streptococcus pneumoniae, including 54 penicillin-resistant strains, was determined by a standardized broth microdilution method. CFC-222, vancomycin and imipenem were the most active agents, with an MIC90 of 0.5 mg/L for the test strains. CFC-222 was 16-fold more pote nt than ciprofloxacin and ofloxacin against all strains tested, includ ing both penicillin-susceptible and -resistant strains. The anti-pneum ococcal activity of fluoroquinolones was not affected by penicillin su sceptibility. These results indicate that CFC-222 is potentially usefu l for treating infection caused by penicillin-resistant strains of S. pneumoniae.