958. Is Dalbavancin a Reliable Treatment Option in Socially Challenged Populations?

Abstract Background Dalbavancin (DAL) is a lipoglycopeptide antibacterial that was granted full FDA approval for the treatment of acute bacterial skin and skin structure infections (ABSSSI) in 2014. Due to its long terminal half-life of 14.4 days, DAL has been used off-label to treat infections that require a prolonged duration of treatment, especially in patients with challenging social situations. We aimed to evaluate the differences in outcomes and clinical effectiveness of DAL, primarily in deep-seated infections in an academic health system. Methods We performed a retrospective review of all the adult patients ( >18 years old) with DAL orders within our health care system between January 1st, 2016, and July 16th, 2021. Baseline characteristics were collected, including age, gender, race, history of illicit drug use disorder (IDUD), diagnosis, and recommended DAL regimen. Follow-up data, including completion of treatment, outpatient visits to infectious diseases clinic, and recurrence of infection within six months, were also collected. Results A total of 50 patients were identified during the study time frame. The median age was 45.5 years, 62% were male, 82% were white, and 62% had a history of IDUD (Table 1). DAL was used predominantly to treat bone and joint infections (e.g., osteomyelitis, septic arthritis), followed by bacteremia, endocarditis, and ABSSSI (Table 1). The most common regimen used is 1500 mg weekly for two doses. Patients with a history of IDUD are less likely to complete the recommended treatment regimen (64.5% vs. 100%; p=0.003), and less likely to follow in the infectious disease clinic (16.1% vs. 52.6%, p=0.016) when compared to patients with no history of IDUD. Twelve patients had either objective evidence or clinical suspicion for recurrence within six months. Although there was a trend for higher recurrence among patients with IDUD (29% vs. 16%), there was no statistical difference with a p-value of 0.332 (Table 2). In addition, DAL was well-tolerated among most patients. Table 1.Baseline characteristics of the study population. Table 2. Outcomes of patients with dalbavancin orders. Conclusion Although DAL is a safe and convenient antimicrobial option, more efforts should be made to establish consistent treatment regimens for its off-label use. Those with social barriers such as IDUD might benefit from additional measures to ensure treatment completion and proper follow-up. Disclosures All Authors: No reported disclosures.