Oritavancin for Staphylococcus Aureus Infections in Opioid Users

This will be an early phase, single center, open label pilot study of 15 participants designed to evaluate the effects of oritavancin in patients with Opioid Use Disorder and/or Intravenous Drug Use and systemic S. aureus infections. In this study systemic infections refers to bacteremia or Infectious Endocarditis. Participants who meet inclusion and exclusion criteria will receive a single 1200mg infusion of oritavancin to complete 4 weeks of antibiotic therapy (including the inpatient phase) for isolated bacteremia and 6 weeks for IE. Participants will be evaluated weekly until completion of treatment and then at week 4 and week 6 after the infusion of oritavancin. Participants will have blood drawn at each visit to monitor for toxicity and pharmacokinetics and will be evaluated clinically and by culture for the presence of relapse of the infection. At the last visit, participants will have an echocardiogram.