Most people with hepatitis C virus (HCV) can be successfully treated with Vosevi (sofosbuvir/velpatasvir/voxilaprevir) after a previous treatment failure, according to study findings published in the Journal of Hepatology. Adding ribavirin to the regimen made little difference in efficacy but led to more adverse events.
Direct-acting antiviral (DAA) regimens such as Epclusa (sofosbuvir/velpatasvir) and Mavyret (glecaprevir/pibrentasvir) are highly effective, curing more than 95% of treated individuals, but a small proportion of patients do not achieve a sustained virological response (SVR). Adding more drugs could help overcome viral resistance and lead to a cure.
Vosevi is a recommended regimen for people with a previous failed round of DAA therapy behind them, but whether adding ribavirin improves efficacy is uncertain. A broad-spectrum antiviral that was widely used with interferon before the advent of modern DAA therapy, ribavirin can cause side effects including nausea, mood swings and anemia.
Samuel Lee, MD, of the University of Calgary Cumming School of Medicine, and colleagues conducted a study to test whether adding ribavirin makes Vosevi more effective for HCV retreatment.
This randomized controlled trial (NCT04695769) included 315 people at five sites in Egypt. More than half were men, and the average age was about 50 years. Most were previously treated with Sovaldi (sofosbuvir) plus Daklinza (daclatasvir), with or without ribavirin.
The participants were randomly assigned to two groups, receiving either Vosevi alone or Vosevi plus a weight-based dose of ribavirin for 12 weeks. If participants achieved SVR—an undetectable HCV viral load 12 weeks after completing therapy—the treatment was considered a success.
In each group, 17 people were lost to follow-up. Based on the number of people initially included in the study at baseline, 87% of participants taking Vosevi alone and 88% of those taking Vosevi plus ribavirin achieved SVR. Based on the number of participants who were retained at the end of the study, 98% and 99%, respectively, were cured.
Both regimens were described as “well tolerated,” and adverse events were uncommon. However, more people taking ribavirin reported side effects including abdominal pain, fatigue and itching. Overall, 55 of 158 people taking Vosevi alone and 77 of 157 taking Vosevi plus ribavirin experienced adverse events. There was only one serious adverse event in the second group, a case of anemia that required ribavirin discontinuation.
“This randomized-controlled trial showed equal, high efficacy of both regimens for the retreatment of previous DAA failures, although ribavirin was associated with more adverse events,” wrote the researchers. “Therefore [sofosbuvir/velpatasvir/voxilaprevir] monotherapy should be the preferred retreatment strategy.”