Review ArticleOverall efficacy and safety results of sofosbuvir-based therapies in Phase II and III studies

The uridine nucleotide analogue sofosbuvir is a selective hepatitis C virus NS5B polymerase inhibitor, active regardless of genotype. We analyzed data on efficacy and safety of sofosbuvir, either in combination with pegylated interferon alfa-2a and ribavirin, or in combination with ribavirin alone as part of an interferon free regimen in more than 1300 patients. Treatment with sofosbuvir for 12 weeks in combination with P/R, in naïve genotype 1 patients was mainly studied in Neutrino. The efficacy of sofosbuvir as part of an all-oral combination including ribavirin alone, was explored in 555 naïve, ineligible and previous treatment failure genotype 2/3 patients. Rates of Sustained Viral Response in genotype 1 and 2 were higher than 85%. For genotype 3 and 4, a European study, Valence, and a US study on patients of Egyptian origin showed that naïve patients are cured at high rates by the all-oral combination given for 24 weeks. The efficacy of sofosbuvir plus P/R for 12 weeks in previous treatment failure genotype 3 has also been demonstrated. Sofosbuvir-based combinations are safe and well tolerated without side effects directly related to the drug. A large body of evidence suggests that sofosbuvir marks a revolution in HCV treatment.