Effectiveness and safety of elbasvir/grazoprevir in korean patients with hepatitis c virus infection: A nationwide real-world study

Background/Aim: This study aimed to establish the real-world effectiveness and safety of grazoprevir/elbasvir (EBR/GZR) therapy in South Korea. Methods: A total of 242 patients with chronic hepatitis C virus (HCV) genotype 1 or 4 infection who started EBR/GZR were consecutively enrolled from seven ter-tiary hospitals. Retrospective analysis of the fractions of patients that achieved sustained virological response (SVR) was performed, and the incidence of adverse events was noted. Results: The mean age of enrolled patients was 59.0 ± 12.6 years and 47.5% were males. Patients with HCV genotype 1b accounted for 93.8% (n = 227), and patients with HCV of unspecified genotype 1 accounted for 5.8% (n = 14). Hypertension was the most common comorbid disease (29.8%) followed by diabetes (22.7%) and chronic kidney disease (CKD, 12.4%). SVR rates of treatment-naïve and treat-ment-experienced patients were 85.5% (182/213) and 93.1% (27/29), respectively, in the intention-to-treat analyses, whereas in the per-protocol analyses, those were 97.8% (179/183) and 100% (28/28), respectively. Fewer patients with HCV genotype 1 of unspecified subtype achieved SVR (81.8%, n = 11) compared to the patients with SVR infected with genotype 1b (99%, n = 198, p < 0.001). All patients with CKD showed SVR. Itching (12%) and dyspepsia (4.1%) were common adverse events. Of the four patients who discontinued the antiviral therapy, one experienced mild fatigue but neither treatment withdrawal was because of an adverse event. Conclusions: EBR/GZR showed high real-world effectiveness and safety in Korean patients with chronic HCV infection regardless of the previous antiviral treat-ment, liver cirrhosis, or CKD status.