Gilead has announced positive results from four Phase 3 clinical studies of once-daily, fixed-dose combination of sofosbuvir (SOF), velpatasvir (VEL), and voxilaprevir (VOX; GS-9857), for the treatment of genotype 1-6 chronic hepatitis C infection. The endpoint for all studies (POLARIS-1, POLARIS-2, POLARIS-3 and POLARIS-4) was sustained viral response after 12 weeks (SVR12).
The POLARIS-1 study was a double-blind, placebo-controlled study in 415 genotype 1-6 NS5A inhibitor-experienced patients. In this study, 96% of patients in the SOF/VEL/VOX group achieved SVR12, versus 0% in the placebo group.
The open-label POLARIS-4 study evaluated the use of SOF/VEL/VOX or SOF/VEL for 12 weeks in 333 genotype 1-4 HCV-infected patients with prior DAA experience that did not include an NS5A inhibitor. In this study, 97% of patients in the SOF/VEL/VOX group achieved SVR12, compared to 90% in the SOF/VEL group.
The open-label POLARIS-2 study evaluated the use of SOF/VEL/VOX for 8 weeks or SOF/VEL for 12 weeks in 941 genotype 1-6 DAA-naïve HCV-infected patients, including 18% with cirrhosis and 23% who had previously failed treatment with an interferon-based regimen. In this study, 95% of patients in the SOF/VEL/VOX group achieved SVR12, compared to 98% in the SOF/VEL group.
The open-label POLARIS-3 study randomized patients with genotype 3 HCV infection and cirrhosis to receive SOF/VEL/VOX daily for 8 weeks or SOF/VEL for 12 weeks. Of the 219 patients treated, 31% had previously failed treatment with an interferon-based regimen. In this study, 96% of patients in the SOF/VEL/VOX group achieved SVR12, compared to 96% in the SOF/VEL group.
The POLARIS-1, POLARIS-3 and POLARIS-4 studies met their respective pre-specified primary endpoints for the patients receiving SOF/VEL/VOX. The POLARIS-2 study did not meet its primary endpoint; with a pre-specified 5% margin, the SVR12 rate for patients receiving treatment with SOF/VEL/VOX for 8 weeks was not statistically non-inferior to the SVR12 rate for patients receiving SOF/VEL for 12 weeks.
The most common adverse events among patients who received SOF/VEL/VOX were headache, fatigue, diarrhea and nausea.
Based on these results Gilead plans to, “submit regulatory applications for SOF/VEL/VOX for the treatment of chronic HCV in the United States in the fourth quarter of 2016,” said Norbert Bischofberger, PhD, EVP of R&D and Chief Scientific Officer at Gilead.
For more information visit Gilead.com.