In vitro activity of trovafloxacin versus ciprofloxacin against clinical isolates.

The comparative in vitro activity of trovafloxacin (CP 99,219), a new fluoroquinolone, was evaluated against 511 clinical isolates. MICs of trovafloxacin were fourfold higher than those of ciprofloxacin for 184 Enterobacteriaceae and 110 non-fermentative gram-negative bacilli. However, trovafloxacin was 16-fold more active than ciprofloxacin against 162 gram-positive staphylococci, pneumococci, streptococci, and enterococci, and two- to fourfold more active against Haemophilus influenzae and Moraxella catarrhalis. MICs of trovafloxacin were correspondingly higher for strains with acquired resistance to ciprofloxacin.