Simeprevir was safer than telaprevir among patients with hepatitis C virus, according to data presented by Medivir AB at the Conference of the Asian Pacific Association for the Study of the Liver.
The phase 3 ATTAIN study of 771 treated adults with chronic HCV and compensated liver disease achieved its primary endpoint by demonstrating the noninferiority of simeprevir compared with telaprevir, Medivir AB reported in a press release. Simeprevir, an NS3/4A protease inhibitor, was co-developed by Medivir AB and Janssen R&D Ireland.
In the study patients were assigned pegylated interferon and ribavirin (PEG-IFN/RBV) with either simeprevir or telaprevir. Simeprevir demonstrated a superior safety profile — including fewer adverse events (pruritis, 31% vs. 43%; fatigue, 32% vs. 38%), serious adverse events (2% vs. 9%) and less anemia (13% vs. 37%) — than telaprevir, the release said.
“We are very pleased to report [the] noninferiority of simeprevir compared to telaprevir, and a superior safety profile in this difficult to treat patient group,” Charlotte Edenius, executive vice president, development, Medivir AB, said in the release. “Moreover, the further analysis of the genotype 1b HCV patients of the phase 3 studies QUEST-1, QUEST-2 and PROMISE demonstrated very high SVR12 rates supporting the strength of simeprevir as a treatment option for this large patient population.”
In the ATTAIN study, patients were randomly assigned 150 mg simeprevir once daily plus PEG-IFN/RBV or 750 mg telaprevir three times daily with PEG-IFN/RBV for 12 weeks, followed by 36 weeks of PEG-IFN/RBV. Forty-four percent of chronic HCV genotype 1 previous null-responders treated with simeprevir and PEG-IFN/RBV achieved the primary endpoint of SVR12 at treatment end compared with 46% of those assigned telaprevir and PEG-IFN/RBV. Among prior partial responders, 70% in the simeprevir arm achieved SVR12 compared with 69% of those assigned telaprevir.
Results from the pooled Quest-1 and Quest-2 studies showed that 85% of treatment-naive patients with HCV genotype 1b achieved SVR12 when treated with simeprevir and PEG-IFN/RBV, compared with 53% of patients treated with placebo and PEG-IFN/RBV, the release said.
During the PROMISE trial, 86% of prior relapse patients with HCV genotype 1b achieved SVR12 when assigned simeprevir and PEG-IFN/RBV vs. 43% of those assigned placebo and PEG-IFN/RBV.