The hepatitis C virus (HCV) NS5A-P32 deletion (P32del) confers potent resistance to NS5A inhibitors. Chronic hepatitis C patients in whom NS5A-P32del variants had emerged during prior direct-acting antiviral (DAA) therapy with an NS5A inhibitor show poor response to DAA retreatment. Here, we report three patients with HCV NS5A-P32del infection who were treated with sofosbuvir, velpatasvir plus ribavirin (SOF/VEL + RBV) in a real-world setting. The patients developed HCV NS5A-P32del, L31F + P32del, or L31V + P32del variants following failure of daclatasvir plus asunaprevir (DCV/ASV) therapy. One of the patients failed to respond to subsequent DCV/ASV and beclabuvir therapy, and the remaining two patients failed to respond to subsequent glecaprevir and pibrentasvir therapy. All three patients completed 24-week SOF/VEL + RBV therapy. Serum HCV RNA became negative at the end of the therapy in all three patients. Two patients with NS5A-P32del and NS5A-L31F + P32del achieved sustained virological response 12 weeks after completion of treatment (SVR12), but HCV relapsed in the remaining NS5A-L13V + P32del patient. Direct sequence analysis detected no additional variants within either the NS5A or NS5B regions at the time of relapse. In conclusion, three patients with prior NS5A-P32del-associated DAA treatment failure received 24 weeks of SOF/VEL + RBV therapy, and two of the patients achieved SVR12.
Keywords: P32 deletion; Resistance-associated substitution; Ribavirin; Sofosbuvir; Velpatasvir.