iconstar paper   Hepatitis C Articles (HCV)  
Back grey arrow rt.gif
Idenix Pharmaceuticals Reports Sustained Virologic Response Rate (SVR4) for Phase II All-Oral Combination Study of Samatasvir (IDX719), a Potent, Pan-Genotypic HCV NS5A Inhibitor, and Simeprevir
  CAMBRIDGE, Mass., Jan. 13, 2014 (GLOBE NEWSWIRE) -- Idenix Pharmaceuticals, Inc. (Nasdaq:IDIX), a biopharmaceutical company engaged in the discovery and development of drugs for the treatment of human viral diseases, today announced interim data from the Company's ongoing phase II 12-week HELIX-1 clinical trial evaluating an all-oral, direct-acting antiviral (DAA) HCV combination regimen of samatasvir (IDX719), Idenix's once-daily pan-genotypic NS5A inhibitor, and simeprevir (TMC435), a once-daily protease inhibitor jointly developed by Janssen R&D Ireland and Medivir AB, plus ribavirin. The combination regimen was well-tolerated in the study. In the treatment-naïve, non-cirrhotic, genotype 1b or 4 HCV-infected patients receiving 50 mg of samatasvir and 150 mg of simeprevir plus ribavirin, 85 percent (n=17/20) remained undetectable for HCV RNA four weeks after completing therapy (SVR4). The 50 mg dose of samatasvir is the selected dose in the ongoing 3-DAA HELIX-2 clinical trial. The HELIX-1 study results are expected to be presented at a scientific meeting in 2014.
"We are pleased with the progress of our program with Janssen, including the announcement of the HELIX-1 SVR4 and safety data, as well as the recent initiation of a second phase II all-oral combination study, HELIX-2," stated Ron Renaud, President and Chief Executive Officer of Idenix. "We also have successfully completed the single-dose portion of the phase I/II clinical trial of IDX21437, a next-generation uridine nucleotide prodrug inhibitor, and the 7-day proof-of-concept portion of the study is underway. Based on these important developments, we are on track to initiate an Idenix-sponsored combination study of samatasvir and IDX21437 by mid-2014."
The HELIX-1 trial is the first study in HCV-infected patients to commence under a non-exclusive collaboration agreement signed with Janssen in January 2013. The HELIX-1 trial is a phase II 12-week, randomized, parallel-group study evaluating the antiviral activity, safety and tolerability of samatasvir and simeprevir in treatment-naïve, non-cirrhotic, genotype 1b or 4 HCV-infected patients. Patients in Part A of the study (n=63) were enrolled in one of three treatment groups receiving 50, 100, or 150 mg samatasvir once-daily for 12 weeks in combination with 150 mg of simeprevir plus a weight-based dose of ribavirin. In Part B of the ongoing HELIX-1 study, exploratory cohorts of patients have been added to evaluate the safety and antiviral activity of simeprevir and ribavirin in combination with 1) a 25 mg dose of samatasvir in genotype 1b-infected patients and 2) a 100 mg dose of samatasvir in genotype 6-infected patients.
A second phase II trial (HELIX-2) was initiated in December 2013 evaluating samatasvir, simeprevir and TMC647055, a once-daily non-nucleoside polymerase inhibitor boosted with low-dose ritonavir being developed by Janssen, with and without ribarivin in genotype 1-infected patients who are either treatment-naïve or have previously relapsed after treatment with interferon and ribavirin.
The combination treatment regimen has been well-tolerated, and there have been no treatment-related serious adverse events in the clinical trial to date. The most frequently reported adverse events were fatigue, pruritus, anemia, nausea and insomnia.
Virologic response data from Part A of the HELIX-1 study are as follows:


"The HELIX-1 study has supported our goal of building the safety profile of samatasvir as part of an all-oral 12-week HCV combination," said Douglas Mayers, M.D., Chief Medical Officer of Idenix. "Based on these data, the 50 mg dose was selected to be evaluated as part of the 3-DAA combination regimen in the recently initiated HELIX-2 clinical trial."
In January 2013, Idenix entered into a non-exclusive collaboration with Janssen Pharmaceuticals for the clinical development of all-oral direct-acting antiviral (DAA) HCV combination therapies. The collaboration is evaluating combinations including samatasvir, simeprevir, and TMC647055. The HELIX-1 and HELIX-2 clinical trials are being conducted by Idenix. Both Idenix and Janssen retain all rights to their respective compounds under the agreement.
Samatasvir is an NS5A inhibitor with low picomolar, pan-genotypic antiviral activity in vitro. To date, samatasvir has been safe and well-tolerated after single and multiple doses of up to 150 mg in healthy volunteers up to 14 days duration, and in HCV-infected patients up to 12 weeks duration. There have been no treatment-related serious adverse events reported in the program. Samatasvir has demonstrated potent pan-genotypic antiviral activity in HCV-infected patients with mean maximal viral load reductions up to approximately 4.0 log10 IU/mL across HCV genotypes 1-4 in a proof-of-concept, three-day monotherapy study.
Simeprevir is an NS3/4A protease inhibitor jointly developed by Janssen R&D Ireland and Medivir AB for the treatment of chronic hepatitis C infection in combination with other antivirals in HCV genotype 1- and 4-infected patients with compensated liver disease, including cirrhosis.
Simeprevir was approved for the treatment of genotype 1 hepatitis C in September 2013 in Japan under the trade name SOVRIAD™, in November 2013 in Canada under the trade name GALEXOS™ and in November 2013 in the United States under the trade name OLYSIO™. A Marketing Authorisation Application was submitted to the European Medicines Agency (EMA) in April 2013 by Janssen-Cilag International NV seeking approval of simeprevir for the treatment of genotype 1 and genotype 4 chronic hepatitis C. To date, more than 3,700 patients have been treated with simeprevir in clinical trials.
Hepatitis C virus is a common blood-borne pathogen infecting three to four million people worldwide annually. The World Health Organization (WHO) estimates that more than 150 million people worldwide are chronically infected with HCV, representing a nearly 5-fold greater prevalence than human immunodeficiency virus.
Idenix Pharmaceuticals, Inc., headquartered in Cambridge, Massachusetts, is a biopharmaceutical Company engaged in the discovery and development of drugs for the treatment of human viral diseases. Idenix's current focus is on the treatment of patients with hepatitis C infection. For further information about Idenix, please refer to www.idenix.com.
CONTACT: Idenix Pharmaceuticals Contact:
Teri Dahlman, (617) 995-9807
  iconpaperstack View Older Articles   Back to Top   www.natap.org