Gilead Sciences’ Vosevi (sofosbuvir/velpatasvir/voxilaprevir) is a highly effective hepatitis C virus (HCV) treatment option for those whose previous direct-acting antiviral (DAA) regimen failed and who have evidence of resistance to certain hep C drug classes, MD Magazine reports.

Publishing their findings in the Journal of Hepatology, researchers conducted a study with 248 people whose hep C had not been cured by a prior DAA treatment for HCV and who had experience taking a medication in the NS5A inhibitor class.

Before 12 weeks of Vosevi treatment, 82.7 percent of the participants had either NS5A inhibitor– or NS3 inhibitor–related resistance-associated substitutions (RASs), which are mutations in hep C linked to drug resistance. A total of 79 percent had RASs to NS5A inhibitors.

Ninety-seven percent of the participants achieved a sustained virologic response 12 weeks after completing therapy (SVR12, considered a cure). There was no association between the initial presence of RASs and the chance of achieving a cure.

Of the seven participants who experienced viral relapse, only one had developed drug resistance prompted by taking Vosevi.

To read the study abstract, click here.