Characteristics and Outcomes of Direct-Acting Antiviral Experienced Patients with Hepatitis C Undergoing Retreatment at an Essential Hospital in the United States.

Background: Hepatitis C virus (HCV) guidelines recommend direct-acting antiviral (DAA) rescue regimens in cases of treatment failure, and first-line regimens for reinfection. In patients with barriers to follow-up after treatment, it is difficult to determine if HCV viremia represents failure or reinfection. Patients are often retreated with rescue regimens despite higher costs. We compared the outcome of first-line vs rescue therapy in DAA experienced patients whose prior outcome was indeterminate. Methods: This retrospective cohort study included DAA experienced adults undergoing retreatment at a hospital in Massachusetts between January 2016 and May 2022. We used descriptive statistics to characterize the population. For patients with an indeterminate prior HCV treatment outcome, we compared the groups' characteristics and outcomes. Results: We included 112 patients. The mean age was 52 years (SD: 12.2), 80.4% were male, and 42.9% were White. Nearly 1 in 4 (25%) reported active substance use. Outcomes of prior DAA treatment included sustained virologic response at 12 weeks in 39.3% (n = 44) and treatment failure in 27.7% (n = 31). The prior treatment outcome was indeterminate in 33% (n = 37). We compared the outcomes of patients with an indeterminate treatment outcome retreated with first-line vs rescue therapy. Sustained virologic response at 12 weeks (66.7 vs 52.7%), treatment failure (0% vs 10.5%), and indeterminate outcome (33.3% vs 36.8%) were similar between the groups ( Conclusions: Outcomes with first-line DAAs were comparable to rescue medications for retreatment of patients with DAA experience and an indeterminate prior treatment outcome. Our findings can help decrease treatment-level barriers for HCV treatment.