Patients with genotype 1 or 3 hepatitis C virus (HCV) infection responded well to therapy with 400 mg of sofosbuvir combined with 100 mg of velpatasvir for 12 weeks, in a randomized, phase II, open-label study conducted in 58 sites in Australia, New Zealand, and the United States.
This treatment program was “well tolerated and highly effective,” according to Dr. Stephen Pianko and his colleagues.
The study participants were divided into three cohorts: the first included patients with genotype 3 HCV infection without cirrhosis, the second included patients with genotype 3 HCV with compensated cirrhosis, and the third included patients with genotype 1 HCV infection that was unsuccessfully treated with a protease inhibitor with peginterferon and ribavirin (50% could have compensated cirrhosis). All patients were treatment experienced and received 12 weeks of drug therapy that included 400 mg of sofosbuvir once daily. Patients in each cohort were randomly assigned to also being treated with 25 mg of velpatasvir once daily with or without ribavirin, or 100 mg of velpatasvir once daily with or without ribavirin.
All patients in cohort 1 who were treated with 400 mg of sofosbuvir combined with 100 mg of velpatasvir or 400 mg of sofosbuvir combined with 100 mg of velpatasvir plus ribavirin experienced a sustained virologic response at week 12 after treatment. The same was true for 100% of patients in cohort 3, who either received 400 mg of sofosbuvir combined with 25 mg velpatasvir or 400 mg of sofosbuvir combined with 100 mg of velpatasvir.
The proportion of patients in the other treatment categories who achieved sustained virologic response 12 weeks following therapy ranged from 58% to 97%.
Eighty-two percent (263 of 321) of patients experienced at least 1 adverse event. Common adverse events included headache and fatigue. "More patients in the groups receiving ribavirin had fatigue, nausea, and pruritus; decreased hemoglobin levels; and increased bilirubin." One patient had an elevated alanine aminotransferase level and y-glutamyl transferase level on treatment day 80, which resulted in treatment discontinuation. Eight study participants experienced "serious adverse events that were not considered to be related to a study drug."
“In summary, sofosbuvir plus 100 mg of velpatasvir provided high rates of [sustained virologic response at week 12 after treatment] in treatment-experienced patients with genotype 1 or 3 HCV infection, including those with compensated cirrhosis, but results will need confirmation in a phase 3 trial,” according to the researchers.
Read the full study in Annals of Internal Medicine (doi: 10.7326/M15-1014).
*This story was updated 11/11/2015.