On- and off-label utilization of dalbavancin and oritavancin for Gram-positive infections

Abstract Background Long-acting lipoglycopeptides (laLGPs) are FDA approved only for acute bacterial skin and skin structure infections (ABSSSIs). However, these antibiotics show promise for off-label use, reductions in hospital length of stay (LOS) and healthcare cost savings. Objectives To assess the effectiveness, safety, impact on LOS and estimated cost savings from laLGP treatment for Gram-positive infections. Methods Retrospective cohort of adult patients who received at least one dose of laLGPs at the University of Colorado Health system. Descriptive statistics were utilized for analysis. Results Of 59 patients screened, 56 were included: mean age 47 years, 59% male and 30% injection drug users/polysubstance abusers (dalbavancin, 71%; oritavancin, 25%; both, 4%). Most common indications for laLGP: ABSSSIs (36%), osteomyelitis (27%) and endocarditis (9%). Most common isolated pathogens: MSSA and MRSA (25% and 19%, respectively), Enterococcus faecalis (11%) and CoNS (11%). Previous antibiotics were administered for a median of 13 days (IQR = 7.0–24.5 days) and laLGPs for a median of one dose (IQR = 1–2 doses). Ten (18%) patients were lost to follow-up. Clinical failure was found in 7/47 (15%) cases with adequate follow-up. Mild adverse effects occurred in six (11%) patients. Projected reduction in hospital LOS and health-system costs were 514 days (9.18 days/person average) and $963456.72 ($17204.58/person average), respectively. Conclusions Prospective trials are needed to validate the use of these antibiotics for Gram-positive infections in practice, with the hope that they will reduce hospital LOS and the need for daily antibiotic infusions to provide alternative options for patients not qualifying for outpatient parenteral antimicrobial therapy.