IN-VITRO ACTIVITY OF CLINAFLOXACIN, TROVAFLOXACIN, AND CIPROFLOXACIN

Clinafloxacin and trovafloxacin are two new fluoroquinolones for which few comparative data are available. When MICs of ciprofloxacin agains t Gram-positive and Gram-negative nosocomial species were compared, cl inafloxacin was the most potent although trovafloxacin was also more a ctive than ciprofloxacin against Staphylococcus aureus and enterococci . All three drugs were bactericidal. Clinafloxacin displayed the lowes t frequency of resistance, approximating 10(-11). Development of resis tance studies over 13-14 passages in the presence of drug revealed a 3 2-fold increase in MIC of clinafloxacin against S. aureus compared wit h 512- and 1024-fold for trovafloxacin and ciprofloxacin respectively, although the three drugs were comparable against Enterococcus faecali s and the Gram-negative bacilli.