Daptomycin compared to standard therapy for the treatment of native valve endocarditis

Introduction: In a recent randomized trial of Staphylococcus aureus bacteremia and native valve endocarditis, daptomycin was found not inferior to standard therapy. We summarized findings in the subgroup of patients with endocarditis according to the Duke criteria. Methods: Patients were randomly assigned to receive daptomycin 6 mg/kg/day or standard therapy (vancomycin 1 g every 12 h or antistaphylococcal penicillin 2 g every 4 h, both with gentamicin 1 mg/kg every 8 h for the first 4 days). The primary end point was success in the modified intent-to-treat population 6 weeks after the end of therapy. Results: Fifty-three patients were included: 35 with right-sided endocarditis (RIE) and 18 with left-sided endocarditis (LIE). The success rates in patients with RIE were similar between daptomycin and the comparator (42% vs 44%). Patients with RIE with septic pulmonary infarcts responded similarly to treatment with daptomycin and standard therapy (60% vs 67%). In the LIE population, treatment success rates were poor in both arms (11% vs 22%). Conclusion: Daptomycin is an efficacious and well-tolerated alternative to standard therapy in the treatment of RIE. Patients with LIE had a poor outcome regardless of the treatment received. Daptomycin is also effective in treating endocarditis with septic pulmonary infarcts.