Prevalence of resistance-associated substitutions to NS3, NS5A and NS5B inhibitors at DAA-failure in hepatitis C virus in Italy from 2015 to 2019

Infez Med. 2021 Jun 1;29(2):242-251.ABSTRACTDespite the high efficacy of direct-acting antivirals (DAAs), the selection of resistance-associated substitutions (RASs) after virological failure of hepatitis C virus (HCV) DAAs can impair the cure of chronic HCV. The aim of the study was to characterize RASs after virological failure of DAAs in Italy over the years. Within the Italian network VIRONET-C, the change in prevalence of NS3/4A-NS5A-NS5B RASs was retrospectively evaluated in patients who failed a DAA regimen over the years 2015-2019. NS3, NS5A and NS5B Sanger sequencing was performed using homemade protocols and the geno2pheno system was used to define HCV-genotype/subtype and predict drug resistance. The changes in the prevalence of RASs over time were evaluated using the chi-square test for trend. Predictors of RASs at failure were analysed by logistic regression. Among 468 HCV-infected patients, HCV genotype 1 was the most prevalent (1b in 154, 33% and 1a in 109, 23%). DAA regimens were: ledipasvir (LDV)/sofosbuvir (SOF) in 131 patients (28%), daclatasvir (DCV)/SOF in 109 (23%), ombitasvir/paritaprevir/ritonavir+dasabuvir (3D) in 89 (19%), elbasvir (EBR)/grazoprevir (GRZ) in 52 (10.5%), velpatasvir (VEL)/SOF in 53 (11%), glecaprevir (GLE)/pibrentasvir (PIB) in 27 (6%) and ombitasvir/paritaprevir/ritonavir (2D) in 7 (1.5%); ribavirin was administered in 133 (28%). The NS5A fasta sequence was available for all patients, NS5B and NS3/4A both for 93%. The prevalence of N...
Source: Infezioni in Medicina - Category: Infectious Diseases Authors: Source Type: research