In vitro bactericidal activity of daptomycin against staphylococci

PC Fuchs, AL Barry, SD Brown - Journal of Antimicrobial …, 2002 - academic.oup.com
PC Fuchs, AL Barry, SD Brown
Journal of Antimicrobial Chemotherapy, 2002academic.oup.com
MICs and minimum bactericidal concentrations (MBCs) of daptomycin, vancomycin, linezolid
and quinupristin–dalfopristin (QD) were determined for 108 staphylococcal isolates. All
strains were susceptible (MICs) to daptomycin (2.0 mg/L) and QD (1.0 mg/L). All but three
isolates were susceptible to vancomycin (4.0 mg/L) and all but one methicillin-resistant
Staphylococcus aureus strain were susceptible to linezolid (4.0 mg/L). QD had the lowest
geometric mean MIC (0.29 mg/L) and daptomycin had the lowest geometric mean MBC …
Abstract
MICs and minimum bactericidal concentrations (MBCs) of daptomycin, vancomycin, linezolid and quinupristin–dalfopristin (Q-D) were determined for 108 staphylococcal isolates. All strains were susceptible (MICs) to daptomycin (2.0 mg/L) and Q-D (1.0 mg/L). All but three isolates were susceptible to vancomycin (4.0 mg/L) and all but one methicillin-resistant Staphylococcus aureus strain were susceptible to linezolid (4.0 mg/L). Q-D had the lowest geometric mean MIC (0.29 mg/L) and daptomycin had the lowest geometric mean MBC (0.57 mg/L). Time–kill tests were performed on 25 isolates. Bactericidal activity (>99.9% kill) was observed with daptomycin at 2 mg/L and at 2 × MBC for 92% of strains tested. In comparison, the bactericidal rates for the other drugs at breakpoint concentrations and at 2 × MBC were 72% and 70% for vancomycin, 46% and 60% for Q-D, and 7% and 14% for linezolid. Of the four drugs tested, daptomycin was bactericidal against the most strains and had the most rapid cidal activity.
Oxford University Press