Initial- and re-treatment effectiveness of glecaprevir and pibrentasvir for Japanese patients with chronic hepatitis C virus-genotype 1/2/3 infections.

<bold>Background: </bold>Glecaprevir and pibrentasvir (GLE/PIB) are potent antiviral agents for hepatitis C virus (HCV) pan-genotypic infections; however, their clinical effectiveness and safety remain limited in the real-world. This study aimed to evaluate viral responses and the safety of GLE/PIB for patients with chronic HCV-1/2/3 infections during both initial- (Arm A) and re-treatment (Arm B) with all-oral direct-acting antiviral agents (DAAs).<bold>Methods: </bold>This prospective-observational cohort study included Japanese patients with chronic HCV-1/2/3 infections (n = 271: 183 in Arm A and 83 in Arm B), who had started receiving GLE/PIB. Primary end point was a sustained virological response (SVR) rate at week 12 (SVR12) after the end of GLE/PIB treatment (EOT).<bold>Results: </bold>SVR12 was achieved by 99.4% of patients (180/181: modified intention-to-treat (mITT) analysis excluding 2 patients lost to follow-up) in Arm A. One patient with an HCV-3b infection who discontinued at week 8 failed to achieve SVR12. SVR12 was achieved by 97.7% of patients (85/87: mITT excluding 1 patient lost to follow-up) in Arm B. Virological relapse occurred in 2 patients with HCV-1b, presenting common 5 loci of resistance-associated substitutions (RASs) including A92 RASs in the NS5A lesion at baseline. Any adverse events (AEs) (grade ≥ 3) occurred in 8 patients (3.0%). 8 patients (3.0%) discontinued due to AEs, however, all of them achieved SVR12.<bold>Conclusions: </bold>Initial and re-treatment with GLE/PIB are effective and safe for Japanese patients with HCV-1/2/3 in real-life settings. Further studies are required to elucidate the mechanism underlying treatment failures of GLE/PIB to completely eradicate HCV worldwide. [ABSTRACT FROM AUTHOR]