Despite High Hepatitis C Virus Testing, Treatment Gaps Remain: A Study Among Syringe Services Program Participants in Massachusetts.

BACKGROUND: People who inject drugs are less likely to initiate hepatitis C virus (HCV) treatment, and less likely to achieve sustained virologic response if they do start, than the general population. The objective of this analysis was to examine whether healthcare experiences were associated with HCV testing and treatment outcomes among people who inject drugs in Massachusetts. METHODS: We analyzed baseline data from an HIV prevention study, which enrolled participants from two Massachusetts syringe service programs from 2020 to 2025. We assessed lifetime HCV testing and treatment outcomes, sociodemographics, substance use behaviors, and healthcare experiences (e.g., comfort with providers) and calculated bivariate associations. RESULTS: Among 185 participants (median age of 40, 43% cisgender women), 97% had ever been tested for HCV; 71% of those tested had ever received a positive test result. However, among those who tested positive, only 41% initiated treatment. Most participants reported comfort discussing their injection drug use with a provider (79%) and feeling welcome in medical clinics (75%). Cisgender men and those feeling welcome in medical clinics reported higher proportions of treatment initiation compared to their counterparts (both p<0.05). CONCLUSIONS: Despite pervasive testing and high treatment completion rates, treatment initiation remains suboptimal. Feeling welcome in medical clinics may be an important, modifiable indicator of HCV treatment engagement. The gap between HCV testing and treatment initiation persists. Understanding factors that shape HCV testing and treatment engagement can generate actionable insights for ongoing elimination efforts in New England.