( Additional Preclinical Data Presented o...)Idenix Reports Results from Two Phase IIb Studies of the,Combination of Valopicitabine and Pegylated Interferon in Hepatitis,C Genotype-1 Patients at the 42nd Annual Meeting of the European,Association for the Study of the Liver,Health

BARCELONA, Spain, April 12, 2007 /PRNewswire-FirstCall/ -- Idenix Pharmaceuticals, Inc. today announced results from two phase IIb studies of the novel combination of valopicitabine (NM283) and pegylated interferon alfa-2a (Pegasys(R)) in both treatment-naive and treatment- experienced patients infected with the genotype-1 strain of the hepatitis C virus (HCV). These data, as well as preclinical data on the active component of valopicitabine in combination with Schering Plough's investigational protease inhibitor boceprevir (SCH 503034), will be presented at the 42nd Annual Meeting of the European Association for the Study of the Liver (EASL).

Pegylated interferon alfa and ribavirin therapy, the current standard of care, is successful in treating 42 - 46 percent of treatment-naive HCV genotype-1 infected patients.(1,2) For patients who do not achieve successful treatment outcomes with pegylated interferon and ribavirin, there are currently no approved treatment options. New antiviral agents are needed to provide more treatment options for patients infected with HCV genotype-1.

"We have learned a great deal about the treatment of patients with hepatitis C, as well as the safety and efficacy of valopicitabine as a result of these large phase IIb trials," said Douglas L. Mayers, executive vice president and chief medical officer of Idenix Pharmaceuticals. "We remain optimistic about the antiviral activity of the combination of valopicitabine and pegylated interferon observed in various patient populations, and believe that multi-drug combinations will play an important role in the treatment of HCV genotype-1 infected patients. We are now working to define valopicitabine's role in therapy, not only in combination with the current standard of care, but also with other investigational compounds in
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