Evolution of late hepatitis C relapse among patients with previous sustained virological responses: An 18-year prospective study.

[BACKGROUND/AIMS] The phenotype of late relapsed hepatitis C virus (HCV) infection (RCI), defined as reappearance of serum HCV RNA in patients with sustained virological responses (SVRs) without reinfection, has yet to be fully elucidated in Asia.

[METHODS] This 18-y prospective study included 1004 Taiwanese SVR patients who were followed up every 3‒6 months. Assessments of late RCI were performed in patients with abnormal alanine aminotransferase levels or occult HCV infection (OCI).

[RESULTS] Among 531 SVR patients tested for OCI, 139 (26.1%) experienced OCI. Of 1004 SVR patients, 2 (0.19%) developed late RCI: one was a 57-y-old genotype 1 HCV-infected male without cirrhosis (patient A) who experienced RCI at 12 months after 12 months of combination therapy with pegylated interferon and ribavirin; the other was a 65-y-old genotype 2 HCV-infected male without cirrhosis (patient B) who experienced RCI at 63 months after 3 months of combination therapy with sofosbuvir and ribavirin and in whom OCI preceded RCI by 36 months. Patients A and B received sofosbuvir/velpatasvir therapy and achieved a 2nd SVR at 10 y and 5 y after the 1st SVR, respectively. Neither late RCI patient had cirrhosis or HCC.

[CONCLUSIONS] During the 18-y follow-up, 0.199% of SVR patients and 0.188% of OCI patients developed late RCI at 1-5 y after the first SVR. In both late RCI patients, 2nd SVR was achieved using sofosbuvir/velpatasvir. Future studies with comprehensive OCI and late RCI assessments are needed to establish the precise relationships of OCI and hepatic events with late RCI.