IN-VITRO ACTIVITY OF DU-6859A, A NEW FLUOROCYCLOPROPYL QUINOLONE

DU-6859a was tested against 844 recent clinical isolates (most from bacteremias) by using reference MIC determination procedures. The activity of DU-6859a against members of the family Enterobacteriaceae was comparable to that of ciprofloxacin (range of MICs for 90% of isolates [MIC(90)], less than or equal to 0.015 to 1 mu g/ml), and the highest MICs were observed among Serratia marcescens and Providencia rettgeri isolates. The DU-6859a MIC(90) for Pseudomonas aeruginosa and Xanthomonas maltophilia was 0.5 mu g/ml. Pneumococci (MIC(90), 0.06 mu g/ml), Haemophilus influenzae (MIC(90) less than or equal to 0.004 mu g/ml), Moraxella catarrhalis (MIC(90), less than or equal to 0.015 mu g/ml), and pathogenic neisseriae (MIC(90), 0.015 to 0.03 mu g/ml) were very susceptible to DU-6859a. All staphylococci had DU-6859a MICs of less than or equal to 1 mu g/ml, including oxacillin- and ciprofloxacin-resistant strains. DU-6859a was very active against isolates resistant to ceftazidime (MIC(90), less than or equal to 0.12 mu g/ml), ciprofloxacin (MIC(90),, less than or equal to 8 mu g/ml), and gentamicin (MIC(90), less than or equal to 1 mu g/ml).