Simeprevir, an investigational NS3/4A protease inhibitor jointly developed by Janssen and Medivir, is currently in Phase 3 studies as a once-daily treatment taken in combination with pegylated interferon and ribavirin for the treatment of genotypes 1 and 4 chronic hepatitis C. It is also being studied in separate Phase 2 trials with other direct-acting antiviral agents as part of interferon-free regimens, with and without ribavirin. This includes a recently initiated Phase 2a trial of an interferon-free regimen with simeprevir and TMC647055, Janssen's non-nucleoside polymerase inhibitor (NNI) currently in development for hepatitis C."We are encouraged by these data, which show sustained viral response and tolerability in both treatment-naive and more challenging-to-cure patients," said Maria Beumont, M.D., Medical Leader for simeprevir, Janssen Research & Development. "We look forward to further evaluating the utility of simeprevir in combination with other agents for the treatment of hepatitis C." About the PILLAR & ASPIRE Trials In the two international, Phase 2b, randomized, double-blind, placebo-controlled studies, patients were either treatment naive (PILLAR) or treatment experienced (ASPIRE), and received pegylated interferon and ribavirin alone or in combination with once-daily simeprevir. In PILLAR, 309 treatment-naive hepatitis C patients received either 75 or 150 mg of once-daily simeprevir for 12 or 24 weeks plus pegylated interferon and ribavirin for 24 or 48 weeks depending on their response to treatment. In ASPIRE, 396 treatment-experienced patients received either 100 or 150 mg of once-daily simeprevir for 12, 24 or 48 weeks plus pegylated interferon and ribavirin for 48 weeks. The post hoc analyses of PILLAR and ASPIRE presented at AASLD (abstracts 83 and 769) evaluated only patients receiving 150 mg of simeprevir and reporting a Metavir score of F3 (PILLAR), or F3 and F4 (ASPIRE). The Metavir score is used to quantify the degree of inflammation and fibrosis of the liver and patients are scored on a four-point scale. An F3 score means the patient has numerous septa (fibrous tissue bands that can decrease the flow of blood through the liver) without cirrhosis, while an F4 score means the patient has cirrhosis. About Simeprevir Simeprevir (TMC435) is a NS3/4A protease inhibitor jointly developed by Janssen and Medivir AB to treat chronic hepatitis C (HCV). Simeprevir is being studied in combination with pegylated interferon and ribavirin, and in combination with direct-acting antiviral agents in all-oral interferon-free regimens, with and without ribavirin. Global Phase 3 studies of simeprevir include QUEST-1 and QUEST-2 in treatment-naive patients, PROMISE in patients who have relapsed after prior interferon-based treatment and ATTAIN in null-responder patients. In parallel to these trials, Phase 3 studies for simeprevir are ongoing in both treatment-naive and treatment-experienced HIV-HCV co-infected patients, HCV genotype 4 patients and in Japanese HCV genotype 1 patients.