Resistance-associated substitutions in relapse after failing hepatitis C direct acting antiviral treatment

Abstract

Introduction: A low rate of failure has been observed with current direct acting antiviral (DAA) regimens, sustained virologic response (SVR) rate of over 95% have been reported. DAA failure was observed rarely in chronic hepatitis C infected (CHC) patients. We aimed to clarify the resistance-associated substitutions (RASs) after the failure of DAA regimen hepatitis C virus (HCV) genotype 1 infections. Methods: We performed a hospital-based analytic study. In this study, 3754 participants were treated with DAA treatment at Liver Center. This study enrolled 14 CHC patients who experienced failure with the DAA regimen in the clinical case study between 2016-2020.The RASs in non-structural protein NS3, NS5A, and NS5B were determined. We evaluated the RASs that were associated with DAA failure in the light of the 2018 EASL HCV guidelines. Results: The HCV relapse rate was about 0.37%. 92.85% of the participants had HCV genotype 1b RASs were detected in all patients Y93H was 84.6%, the most detected RAS in GT1b infected patients complex RAS-pattern L31M/V/ I+Y93H was observed GT1b participants with 61.5%. Patients who had failed DAA treatment in GT 1b were able to increase significantly the level of resistance compared to single RASs.