1553. Efficacy and Safety of Dalbavancin and Oritavancin in the Treatment of Gram-Positive Infections

Background Lipoglycopeptides are approved for acute bacterial skin and skin structure infections (ABSSSI), but are often used in other infections, including osteomyelitis (OM) and bloodstream infections (BSI). Methods This retrospective cohort study included VA St. Louis Health Care System patients aged ≥18 through ≤89 years treated for ABSSSI, BSI, or OM with lipoglycopeptides. Patients were excluded if they received ≥72 hours (ABSSSI, BSI) or ≥7 days (OM) of antibiotics prior to lipoglycopeptide administration or other intravenous antibiotics were administered for ≥48 hours after lipoglycopeptide. The primary efficacy outcome was clinical success in the lipoglycopeptide cohort, defined per infection. Secondary outcomes were a comparison of clinical success in the lipoglycopeptide cohort to historical controls of patients treated at the VA St. Louis for ABSSSI, BSI, or OM. A multivariate regression was also conducted to find factors in the lipoglycopeptide group independently associated with clinical success. Safety outcomes compared adverse drug reactions between single- and 2-dose regimens of lipoglycopeptides. Results A total of 36 patients were included in the analysis; no patients met inclusion for bloodstream infection. Twenty-nine patients were treated for ABSSSI and 7 patients met inclusion for OM treatment. Dalbavancin was the agent used most often for both OM (4/7) and ABSSSI (22/29). The primary outcome of clinical success occurred in 77.7% (28/36) of the lipoglycopeptide cohort. There was no difference in clinical success between the lipoglycopeptide cohort and historical controls for ABSSSI (86% [5/29] vs 84% [159/189], p >0.05) or OM (43% [3/7] vs 58% [83/143], p >0.05). No difference in adverse outcomes between single- and 2-dose regimens of lipoglycopeptide were observed. Conclusion Clinical success for patients treated with lipoglycopeptides for ABSSSI and OM in this small cohort were comparable to historical controls. No difference was identified in the safety between single- and 2-dose regimens of lipoglycopeptides. Disclosures All Authors: No reported disclosures