SAN FRANCISCO — A fixed-dose combination of Sovaldi and velpatasvir yielded better sustained virologic response rates in patients with genotype 2 hepatitis C virus than Sovaldi and ribavirin, the current standard of care, according to findings presented at The Liver Meeting 2015.
Mark S. Sulkowski, MD, of Johns Hopkins University, noted that there is currently no ribavirin-free regimen approved for the treatment of this patient population. The open-label study had broad inclusion criteria, allowing for patients with treatment experience and cirrhosis, and was conducted at 51 centers in the U.S.
The primary endpoint was SVR at 12 weeks. The aim was to establish the noninferiority of the Sovaldi (sofosbuvir, Gilead Sciences) and velpatasvir (GS-5816, Gilead Sciences) combination with a 10% margin. Adverse events, discontinuations and lab abnormalities also underwent analysis.
Mark S. Sulkowski
There were 134 patients in the sofosbuvir/velpatasvir arm and 132 in the sofosbuvir/ribavirin arm. One patient in the velpatasvir arm stopped treatment due to an adverse event on day 1 and one patient in the ribavirin arm was lost to follow-up after week 10.
SVR12 was 99% for the velpatasvir group and 94% for the ribavirin group. Sulkowski highlighted a strata-adjusted difference of 5.2%. “Sofosbuvir/velpatasvir was superior to the standard of care sofosbuvir and ribavirin,” he said.
There were six relapses and two patients lost to follow-up in the standard of care group after treatment ended.
The velpatasvir regimen yielded SVR12 rates at or near 100% among cirrhotics, compared with a peak rate of 96% among cirrhotics treated with sofosbuvir/ribavirin.
All patients with NS5A resistance-associated variants (RAVs) in the velpatasvir arm reached SVR12. “Thus, NS5A RAVs had no impact on the efficacy of sofosbuvir/velpatasvir,” Sulkowski said.
Adverse events occurred in 69% of patients in the study regimen group and 77% of those in the standard of care group. Grade 3 or 4 event rates were slightly higher in the standard therapy group. Fatigue, headache, nausea and insomnia occurred in more than 10% of patients in both study arms, but were slightly more frequent in the sofosbuvir/ribavirin arm.
There were two deaths in the velpatasvir group, but neither was determined to be related to the study regimen.
“This regimen is currently under regulatory review,” Sulkowski said. – by Rob Volansky
Sulkowski MS, et al. Abstract 205. Presented at: The Liver Meeting; Nov. 13-17, 2015; San Francisco.
Disclosures: Sulkowski reports being on the advisory committees or review panels of Abbvie, Bristol-Myers Squibb, Gilead, Janssen and Merck and receiving grant or research support from those same companies. Please see the full study for a list of all other authors’ relevant financial disclosures.