The impact of SVR from direct-acting antiviral- and interferon-based treatments for HCV on hepatocellular carcinoma risk.

We evaluated the effect of sustained virologic response (SVR) from direct-acting antiviral (DAA)- and interferon-based treatments on hepatocellular carcinoma (HCC) risk in a large population-based cohort in Canada. We used data from the BC Hepatitis Testers Cohort, which includes ~1.3 million individuals tested for HCV since 1990, linked with healthcare administrative and registry datasets. Patients were followed from the end of HCV treatment to HCC, death or 31 December 2016. We assessed HCC risk among those who did and did not achieve SVR by treatment type using proportional hazard models. Of 12 776 eligible individuals, 3905 received DAAs while 8871 received interferon-based treatments, followed for a median of 1.0 [range: 0.6-2.7] and 7.9 [range: 4.4-17.1] years, respectively. A total of 3613 and 6575 achieved SVR with DAAs- and interferon-based treatments, respectively. Among DAAs-treated patients, HCC incidence rate was 6.9 (95%CI: 4.7-10.1)/1000 person yr (PY) in SVR group (HCC cases: 26) and 38.2 (95%CI: 20.6-71.0) in the no-SVR group (HCC cases: 10, P < .001). Among interferon-treated individuals, HCC incidence rate was 1.8 (95%CI: 1.5-2.2) in the SVR (HCC cases: 99) and 13.9 (95%CI: 12.3-15.8) in the no-SVR group (HCC cases: 239, P < .001). Compared with no-SVR from interferon, SVR from DAA- and interferon-based treatments resulted in significant reduction in HCC risk (adjusted subdistribution hazard ratio (adjSHR) DAA = 0.30, 95%CI: 0.19-0.48 and adjSHR interferon = 0.2, 95%CI: 0.16-0.26). Among those with SVR, treatment with DAAs compared to interferon was not associated with HCC risk (adjSHR = 0.93, 95%CI: 0.51-1.71). In conclusion, similar to interferon era, DAA-related SVR is associated with 70% reduction in HCC risk.