Eight weeks of therapy with a combination of sofosbuvir, velpatasvir and voxilaprevir does not appear to be as effective as 12 weeks of sofosbuvir plus velpatasvir in patients with chronic hepatitis C virus (HCV) infection, according to the results of two phase 3 randomized clinical trials.
Studies show that patients with chronic HCV infection have high rates of sustained virologic response (SVR) following 12 weeks of treatment with the nucleotide polymerase inhibitor sofosbuvir combined with the NS5A inhibitor velpatasvir. However, a shorter duration of therapy for HCV may help limit the decline in patient compliance with longer courses of therapy. Nonadherence has become the biggest risk factor for treatment failure.
Researchers led by Ira M. Jacobson, MD, professor of medicine at the Icahn School of Medicine at Mount Sinai in New York, assessed the efficacy of eight weeks of treatment with sofosbuvir and velpatasvir plus the pangenotypic NS3/4A protease inhibitor voxilaprevir in comparison to standard 12 weeks of sofusbuvir-velpatasvir.
The researchers published their results online on April 5, 2017 in the journal Gastroenterology.
In a pair of phase 3, open-label trials, patients with HCV infection who had not previously been treated with a direct-acting antiviral (DAA) agent were randomly assigned to groups given sofosbuvir-velpatasvir-voxilaprevir for eight weeks or sofosbuvir-velpatasvir for 12 weeks.
One trial, POLARIS-2, enrolled 941 patients from 117 sites in the United States, Canada, the United Kingdom, France, Germany, Australia and New Zealand who were infected with all HCV genotypes with or without cirrhosis, except patients with HCV genotype 3 and cirrhosis, who are more difficult to treat. This trial was designed to test the non-inferiority of eight weeks of sofosbuvir-velpatasvir-voxilaprevir to 12 weeks of sofosbuvir-velpatasvir.
The other trial, POLARIS-3, enrolled 219 patients infected with HCV genotype 3 who had cirrhosis. It compared rates of SVR in both DAA combination treatments.