Outcomes from a large 10 year hepatitis C treatment programme in people who inject drugs: No effect of recent or former injecting drug use on treatment adherence or therapeutic response

BACKGROUND AND AIMS People who inject drugs (PWID) are historically viewed as having "difficult to treat" hepatitis C disease, with perceived inferior treatment adherence and outcomes, and concerns regarding reinfection risk. We evaluated for differences in treatment adherence and response to Peginterferon-alfa-2a/Ribavirin (Peg-IFNα/RBV) in a large urban cohort with and without a history of remote or recent injection drug use. METHODS Patient data was retrospectively reviewed for 1000 consecutive patients-608 former (no injecting drug use for 6 months of therapy), 85 recent (injecting drug use within 6 months) PWID, and 307 non-drug users who were treated for chronic hepatitis C with Peg-IFNα/RBV. The groups were compared for baseline characteristics, treatment adherence, and outcome. RESULTS There was no significant difference in treatment non-adherence between the groups (8.4% in PWID vs 6.8% in non-PWIDs; RR = 1.23, CI 0.76-1.99). The overall SVR rate in PWID (64.2%) was not different from non-PWIDs (60.9%) [RR = 1.05, 95% CI 0.95-1.17]. There was no significant difference in SVR rates between the groups controlling for genotype (48.4% vs 48.4% for genotype 1; 74.9 vs 73.3% for genotype 3). Former and recent PWID had similar adherence rates. CONCLUSIONS PWID have comparable treatment adherence and SVR rates when compared to non-drug users treated with Peg-IFNα/RBV. These data support a public health strategy of HCV treatment and eradication in PWID in the DAA era.