Ruben, Brandão,Rute, Marcelino,Goncalves, Maria de FátimaDiogo, IsabelCarvalho, A PCabanas, JoaquimCosta, InêsBrogueira, PedroVentura, FMiranda , Ana CláudiaMansinho, KamalGomes, P2021-05-032021-05-032018-04-261999-4915PURE: 6140247PURE UUID: a3a75ce9-3a04-4d2e-a04c-91697a22e7f3Scopus: 85046272851PubMed: 29701642PubMedCentral: PMC5977216http://hdl.handle.net/10362/116851This study is focused on the prevalent NS5 coding region resistance-associated substitutions (RASs) in DAA-naive genotype (GT)1 HCV-infected patients and their potential impact on success rates. Plasma RNA from 81 GT1 HCV-infected patients was extracted prior to an in-house nested RT-PCR of the NS5 coding region, which is followed by Sanger population sequencing. NS5A RASs were present in 28.4% (23/81) of all GT1-infected patients with 9.9% (8/81) having the Y93C/H mutation. NS5B RASs showed a prevalence of 14.8% (12/81) and were only detected in GT1b. Overall 38.3% (31/81) of all GT1 HCV-infected patients presented baseline RASs. The obtained data supports the usefulness of resistance testing prior to treatment since a statistically significant association was found between treatment failure and the baseline presence of specific NS5 RASs known as Y93C/H (p = 0.04).141462364engDirect-acting antiviralsHepatitis C virusNS5ANS5BResistance-associated substitutionsSDG 3 - Good Health and Well-beingjournal article10.3390/v10050223https://www.ncbi.nlm.nih.gov/pubmed/29701642