CHIME - A tailored HCV microelimination project in Viennese people who inject drugs at drug centralized substitution centers.

Background: Hepatitis C remains highly prevalent among people who inject drugs (PWIDs). We propose an integrated approach for screening/diagnostic testing and treatment in 6,665 Viennese PWIDs registered to access opioid agonist therapy (OAT). Methods: OAT prescriptions were required monthly at one of nine approved authorities, making them ideal platforms for hepatitis C virus (HCV) screening. All PWIDs attending these authorities between January 2019 and March 2020 were offered on-site HCV screening, and consecutive HCV RNA PCR in case of positive HCV serology. In HCV viremic PWIDs, offsite referral to HCV care and treatment according to directly observed therapy (DOT) alongside OAT were performed. Results: 4,327/6,665 (64.9%) individuals were contacted before the COVID-19-related project discontinuation. There were 1,538/4,327 (35.5%) individuals who had participated in the study. HCV serology was available in 1,510/1,538 (98.2%): 795/1,519 (52.6%) had a positive serology, among whom 632 (79.5%) were followed-up with a PCR test. In 8/1,538 (0.5%) additional study participants HCV RNA PCR was assessed without prior serological screening. 239/640 (37.3%) individuals were HCV viremic with 51 (21.3%) having started on direct-acting antivirals (DAAs). 48/51 (94.1%) had completed treatment, among whom 42 (87.5% according to ITT) had achieved sustained virologic response at 12 weeks after completing treatment (SVR12) and 6 (12.5%) had been lost to follow-up after completion of therapy (SVR12 according to mITT: 42/42, 100%). No treatment failures had occurred. Conclusion: Providing integrated point-of-care HCV screening/diagnostic testing at central OAT approved centers, followed by DOT with DAAs, represents an effective HCV microelimination strategy. While some PWIDs were lost in the cascade to cure and the absolute number of SVR was limited by the COVID-19 pandemic, our approach will allow linkage to care in a large proportion of Viennese PWIDs.