Safety, Tolerability and Efficacy of Sofosbuvir, Velpatasvir, and Voxilaprevir in Subjects With Previous DAA Experience

The treatment of chronic Hepatitis C with combination directly acting antiviral agents (DAAs) represents a dramatic improvement over previous therapies in safety, tolerability and efficacy, but these therapies are not universally effective. Some patients fail to achieve sustained virologic response (SVR) following therapy with combination DAAs, yet the ideal retreatment strategy for these patients has not yet been determined. As DAA medications become more widely available outside clinical trial settings, it is important to evaluate retreatment strategies in patients who fail combination DAA therapy, regardless of whether they had virologic failure, post-treatment relapse, or discontinued treatment prematurely. The RESOLVE study will evaluate the safety, tolerability, and efficacy of treatment with a fixed dose combination of sofosbuvir (an approved NS5B inhibitor), velpatasvir (formerly GS-5816, a second generation NS5A inhibitor) and voxilaprevir (formerly GS-9857, an approved NS3/4A protease inhibitor) in HCV infected patients with early and advanced liver disease, including those with HIV or hepatitis B, who have failed previous combination DAA therapy. Patients with early stage and compensated cirrhosis will receive 12 weeks of therapy, and be followed for adverse events and SVR following completion of therapy. RESOLVE will aid our understanding of the determinants of response to re-treatment with combination DAA therapy * With and without cirrhosis * In patients with HCV GT1 subtypes a and b * In patients who previously failed DAA therapy * With and without HIV or hepatitis B RESOLVE will also examine factors associated with treatment response, including * the viral and pharmacokinetics of patients receiving the combination of SOF/VEL/VOX, in patients with and without cirrhosis * differential interferon sensitive gene responses * host genetic and proteomic factors * evolution of HCV quasispecies and resistance associated variants at baseline and in response to therapy * changes in host HCV-specific immunity in patients with and without advanced liver disease