Daptomycin is more efficacious than vancomycin against a methicillin-susceptible Staphylococcus aureus in experimental meningitis

Abstract

Objectives: To test the efficacy of daptomycin, a cyclic lipopeptide antibiotic, against a methicillin-susceptible Staphylococcus aureus strain in experimental rabbit meningitis and to determine its penetration into non-inflamed and inflamed meninges Results: Over a treatment period of 8 h, daptomycin (15 mg/kg) was significantly superior to the comparator regimen vancomycin (−4.54 ± 1.12 log₁₀/mL for daptomycin versus −3.43 ± 1.17 log₁₀/mL for vancomycin). Daptomycin managed to sterilize 6 out of 10 CSFs compared with 4 out of 10 for vancomycin. The penetration of daptomycin into inflamed meninges was ∼5% and ∼2% into non-inflamed meninges. Conclusions: The superior bactericidal activity of daptomycin was confirmed in vivo and in time-killing assays in vitro.