Reduction in the population prevalence of hepatitis C virus viraemia among people who inject drugs associated with scale-up of direct-acting anti-viral therapy in community drug services: real-world data

Abstract

Background and aims: There has been little empirical evidence to show the 'real-world' impact of scaling-up direct-acting anti-viral (DAA) treatment among people who inject drugs (PWID) on hepatitis C virus (HCV) viraemia at a population level. We aimed to assess the population impact of rapid DAA scale-up to PWID delivered through community services-including drug treatment, pharmacies, needle exchanges and prisons-in the Tayside region of Scotland, compared with Greater Glasgow and Clyde (GGC) and the Rest of Scotland (RoS).

Design, setting and participants: Natural experiment, evaluated using data from national biennial surveys of PWID and national clinical data. Services providing injecting equipment (2010-18) and HCV treatment clinics (2017-18) across Scotland. A total of 12 492 PWID who completed a questionnaire and provided a blood spot (tested for HCV-antibodies and RNA); 4105 individuals who initiated HCV treatment.

Intervention and comparator, measurements: The intervention was rapid DAA scale-up among PWID, which occurred in Tayside. The comparator was GGC/RoS. Trends in HCV viraemia and uptake of HCV therapy over time; sustained viral response (SVR) rates to therapy by region and treatment setting.

Findings: Uptake of HCV therapy (last year) among PWID between 2013-14 and 2017-18 increased from 15 to 43% in Tayside, 6 to 16% in GGC and 11 to 23% in RoS. Between 2010 and 2017-18, the prevalence of HCV viraemia (among antibody-positives) declined from 73 to 44% in Tayside, 67 to 58% in GGC and 64 to 55% in RoS. The decline in viraemia was greater in Tayside [2017-18 adjusted odds ratio (aOR) = 0.47, 95% confidence interval (CI) = 0.30-0.75, P = 0.001] than elsewhere in Scotland (2017-18 aOR = 0.89, 95% CI = 0.74-1.07, P = 0.220) relative to the baseline of 2013-14 in RoS (including GGC). Per-protocol SVR rates among PWID treated in community sites did not differ from those treated in hospital sites in Tayside (97.4 versus 100.0%, P = 0.099).

Conclusions: Scale-up of direct-acting anti-viral treatment among people who inject drugs can be achieved through hepatitis C virus (HCV) testing and treatment in community drug services while maintaining high sustained viral response rates and, in the Tayside region of Scotland, has led to a substantial reduction in chronic HCV in the population.

Keywords: Hepatitis C, Chronic; Substance Abuse, Intravenous; Viremia; direct-acting anti-virals; prevalence; sustained viral response.