BackgroundIran is among countries with high opioid agonist therapy (OAT) coverage in prisons, which provides an infrastructure to increase feasibility of HCV programs. We aimed to evaluate the impact of an intervention to improve HCV screening, diagnosis, and treatment, including alongside the provision of OAT, in an Iranian prison. MethodsDuring July-December 2018, in the Gorgan prison, all incarcerated adults (>18 years) received HCV antibody rapid testing and, if positive, provided a venepuncture sample for HCV RNA testing. Participants with positive RNA received direct-acting antiviral (DAA) therapy [(Sofosbuvir/Daclatasvir) for 24 or 12 weeks, respectively, for those with and without cirrhosis]. Response to treatment was measured by the sustained virological response at 12 weeks post-treatment (SVR12). ResultsAmong 2015 incarcerated people with a median age of 35 years (IQR:29–41), the majority were male (97%), had not finished high school (68%), and had a history of drug use (71%), of whom 15% had ever injected drugs. A third of participants were receiving OAT, including 54% of those who had ever injected. HCV antibody prevalence was 6.7%, and RNA was detected in 4.6% of all participants; this prevalence was 32.6% and 24.7% among those with a history of injection, respectively. Treatment uptake was 82% (75/92) and was similar among people on OAT and those with a history of injection (81%). The majority completed treatment in prison and were available for SVR12 assessment (71%, 53/75). Achieved SVR12 was 100% (53/53) based on the available case analysis; those who did not have available SVR12 were released either prior to treatment initiation or completion (n = 39). ConclusionThe availability of OAT infrastructure should be considered as an opportunity for enhancing HCV care in prisons. Where resources are limited, the prison harm reduction network could be used to design targeted HCV programs among people who are at higher risk of infection.