BAY 12-8039, a novel fluoroquinolone: Activity against important respiratory tract pathogens

Abstract

BAY 12-8039 or moxifloxacin is a new 8-methoxyquinolone with documented, improved activity against Gram-positive cocci and anaerobic bacteria. This study tested 1250 commonly isolated respiratory tract pathogens (251 Moraxella catarrhalis, 499 Haemophilus influenzae, 500 Streptococcus pneumoniae) from 1996–1997 clinical infections at more than 30 medical centers. Among the M. catarrhalis strains (81% β-lactamase–positive) the BAY 12-8039 MIC 90 was 0.06 μg/mL, a potency equal to ofloxacin but less than all other tested fluoroquinolones (ciprofloxacin, clinafloxacin, levofloxacin, sparfloxacin, trovafloxacin). The H. influenzaestrains were generally less susceptible to BAY 12-8039 (MIC 90, 0.03 μg/mL) than the tested fluoroquinolones, and the other comparison compounds were less active overall. All S. pneumoniae strains were susceptible to BAY 12-8039 at ≤0.25 μg/mL (MIC 90, 0.06–0.12 μg/mL), a value equal-potent to trovafloxacin. This new fluoroquinolone, BAY 12-8039, appears promising for the treatment of community-acquired respiratory tract infections caused by common bacterial species.