High hepatitis C treatment uptake among people with recent drug dependence in New South Wales, Australia

Background & Aims: High HCV treatment uptake among people at most risk of transmission is essential to achieve elimination. We aimed to characterise subpopulations of people with HCV based on drug dependence, to estimate direct-acting antiviral (DAA) uptake in an unrestricted treatment era, and to evaluate factors associated with treatment uptake among people with recent drug dependence. Methods: HCV notifications in New South Wales, Australia (1995-2017) were linked to opioid agonist therapy (OAT), hospitalisations, incarcerations, HIV notifications, deaths, and prescription databases. Drug dependence was defined as hospitalisation due to injectable drugs or receipt of OAT, with indicators in 2016-2018 considered recent. Records were weighted to account for spontaneous clearance. Logistic regression was used to analyse factors associated with treatment uptake among those with recent drug dependence. Results: 57,467 people were estimated to have chronic HCV throughout the DAA era. Treatment uptake was highest among those with recent (47%), compared to those with distant (38%), and no (33%) drug dependence. Among those with recent drug dependence, treatment was more likely among those with HIV (adjusted odds ratio [aOR] 1.71; 95% CI 1.24–2.36), recent incarceration (aOR 1.10; 95% CI 1.01–1.19), and history of alcohol use disorder (aOR 1.22; 95% CI 1.13–1.31). Treatment was less likely among women (aOR 0.78; 95% CI 0.72–0.84), patients of Indigenous ethnicity (aOR 0.75; 95% CI 0.69–0.81), foreign-born individuals (aOR 0.86; 95% CI 0.78–0.96), those with outer-metropolitan notifications (aOR 0.90; 95% CI 0.82–0.98), HBV coinfection (aOR 0.69; 95% CI 0.59–0.80), and >1 recent hospitalisation (aOR: 0.91; 95% CI 0.84–0.98). Conclusions: These data provide evidence of high DAA uptake among people with recent drug dependence, including those who are incarcerated. Enhancing this encouraging initial uptake among high-risk populations will be essential to achieve HCV elimination. Lay summary: To facilitate HCV elimination, those at highest risk of infection and transmission are a treatment priority. This study shows the successes of Australia's universal provision of DAA therapy in reducing the barriers to treatment which have historically persisted among people who inject drugs. Despite higher DAA therapy uptake among those with recent drug dependence, gaps remain. Strategies which aim to reduce marginalisation and increase treatment uptake to ensure equitable HCV elimination must be advanced.