Outcomes in Patients with Staphylococcus aureus Bacteremia Treated with Dalbavancin in Clinical Trials

Introduction Dalbavancin is a long-acting, bactericidal, lipoglycopeptide antibiotic approved by the US Food and Drug Administration and the European Medicines Agency for treatment of acute bacterial skin and skin structure infections in adults, with potent activity against Gram-positive pathogens, including methicillin-susceptible and methicillin-resistant Staphylococcus aureus. Here we describe the clearance and clinical outcomes of patients with S. aureus bacteremia in five clinical trials of skin and skin structure infections or catheter-related bloodstream infections that evaluated the efficacy and safety of dalbavancin. Methods Patients with uncomplicated S. aureus bacteremia identified in blood cultures drawn at baseline (before study drug) with at least one follow-up blood culture are described from four phase 3 trials in skin and skin structure infections and one phase 2 catheter-related infection study. Dalbavancin was administered as a single-dose (1500 mg intravenous [IV]) or a two-dose regimen (1000 mg IV on day 1, 500 mg IV on day 8). Comparators included vancomycin IV or linezolid IV/oral for 10-14 days. Results All 39 patients (100%) who received dalbavancin, including 8 patients on the single-dose regimen, had clearance of bacteremia versus 19/20 patients (95%) treated with comparators (vancomycin or linezolid). At end of treatment, 33/36 dalbavancin-treated patients (92%) achieved clinical success versus 18/23 patients (78%) treated with comparators. Conclusions All 39 patients with uncomplicated S. aureus bacteremia treated with dalbavancin (single- or two-dose regimen) and with follow-up blood cultures had clearance of their bloodstream infection. Clinical response rates were similar to daily comparator therapy for 10-14 days.