Outcomes of Interferon-free Treatment of Hepatitis C Virus Infection Seven Years after Approval and Problems with Drop out during and after Treatment: A Retrospective, Single-center Study.

Objective This retrospective, single-center study assessed the effects of interferon (IFN)-free treatment of hepatitis C virus (HCV) infection, which has been approved for seven years; calculated the incidence of hepatocellular carcinoma (HCC) after achieving a sustained virologic response (SVR); and elucidated problems with follow-up for surveillance of post-SVR HCC, particularly the impact of the coronavirus disease 2019 (COVID-19) pandemic. Methods We summarized the SVR achievement rate of 286 HCV-infected patients who received 301 IFN-free treatments and analyzed the cumulative incidence of initial HCC and the cumulative continuation rate of follow-up after SVR in the 253 patients who achieved SVR and did not have a history of HCC. Results Among 286 patients who received IFN-free treatments, 14 dropped out, and the 272 remaining patients achieved an SVR after receiving up to third-line treatment. Post-SVR HCC occurred in 18 (7.1%) of the 253 patients without a history of HCC, with a cumulative incidence at 3 and 5 years after SVR of 6.6% and 10.0%, respectively; the incidence of cirrhosis at those time points was 18.2% and 24.6%, respectively.Of the 253 patients analyzed, 58 (22.9%) discontinued follow-up after SVR. Patients who had no experience with IFN-based therapy tended to drop out after SVR. Notably, the number of dropouts per month has increased since the start of the pandemic. Conclusion Currently, IFN-free treatment is showing great efficacy. However, the incidence of HCC after SVR should continue to be monitored. In this study, the COVID-19 pandemic did not affect treatment outcomes, but it may affect surveillance for post-SVR HCC.