Combining treatment for chronic hepatitis C with opioid agonist therapy is an effective microelimination strategy for people who inject drugs with high risk of non-adherence to direct-acting antiviral therapy.

ABSTRACT

Background & aims: Despite effective direct-acting antivirals (DAAs), hepatitis C virus (HCV) prevalence is high among people who inject drugs (PWIDs) and non-adherence to therapy remains a major obstacle towards HCV elimination in this subpopulation. To overcome this issue, we have combined ongoing opioid agonist therapy (OAT) with DAAs in a directly-observed therapy (DOT) setting. Method: From September 2014 until January 2021 PWIDs at high risk of non-adherence to DAA therapy, who were also on OAT, were included into this microelimination project. Individuals received their OAT and DAAs under supervision of healthcare workers as DOT in a pharmacy or low-threshold facility. Results: In total, 504 HCV RNA-positive PWIDs on OAT (387 men, 76.8%; median age 38 years [IQR 33-45], HIV 4.6%; hepatitis B 1.4%) were included into this study. Two thirds reported ongoing intravenous drug use (IDU) and half of them had no permanent housing. Only 41 (8.1%) were lost to follow-up and two (0.4%) died of reasons unrelated to DAA toxicity. Overall, 90.7% of PWIDs achieved sustained virological response 12 weeks after treatment (SVR12) (95% CI 88.1-93.2%). By excluding those lost to follow-up and hose who had died of causes unrelated to DAAs, the SVR12 rate was 99.1% (95% CI 98.3-100.0%; modified intention-to-treat analysis). Four PWIDs (0.9%) experienced treatment failure. Over a median follow-up of 24 weeks (IQR 12-39), 27 reinfections (5.9%) were observed in individuals with the highest IDU rates (81.2%). Importantly, even though some were lost to follow-up, all completed their DAA treatment. By using DOT, adherence to DAAs was excellent with only a total of 86 missed doses (0.3% of 25,224 doses). Conclusions: In this difficult-to-treat population of PWIDs with high rates of IDU , coupling DAA treatment to OAT in a DOT setting resulted in high SVR12 rates equivalent to conventional treatment settings in non-PWID populations.