Background: Effective treatment for hepatitis C virus (HCV) genotype 1 infection in patients who have not had a sustained virologic response to prior interferon-based therapy represents an unmet medical need.
Methods: We conducted a phase 3, randomized, open-label study involving patients infected with HCV genotype 1 who had not had a sustained virologic response after treatment with peginterferon and ribavirin, with or without a protease inhibitor. Patients were randomly assigned to receive the NS5A inhibitor ledipasvir and the nucleotide polymerase inhibitor sofosbuvir in a once-daily, fixed-dose combination tablet for 12 weeks, ledipasvir-sofosbuvir plus ribavirin for 12 weeks, ledipasvir-sofosbuvir for 24 weeks, or ledipasvir-sofosbuvir plus ribavirin for 24 weeks. The primary end point was a sustained virologic response at 12 weeks after the end of therapy.
Results: Among the 440 patients who underwent randomization and were treated, 20% had cirrhosis and 79% had HCV genotype 1a infection. The rates of sustained virologic response were high in all treatment groups: 94% (95% confidence interval [CI], 87 to 97) in the group that received 12 weeks of ledipasvir-sofosbuvir; 96% (95% CI, 91 to 99) in the group that received 12 weeks of ledipasvir-sofosbuvir and ribavirin; 99% (95% CI, 95 to 100) in the group that received 24 weeks of ledipasvir-sofosbuvir; and 99% (95% CI, 95 to 100) in the group that received 24 weeks of ledipasvir-sofosbuvir and ribavirin. No patient discontinued treatment owing to an adverse event. The most common adverse events were fatigue, headache, and nausea.
Conclusions: Treatment with a once-daily, single-tablet regimen of ledipasvir and sofosbuvir resulted in high rates of sustained virologic response among patients with HCV genotype 1 infection who had not had a sustained virologic response to prior interferon-based treatment. (Funded by Gilead Sciences; ION-2 ClinicalTrials.gov number, NCT01768286.).