InterMune extends hepatitis C drug discovery program with Array BioPharma.

InterMune, Inc. announced the presentation of preclinical data on the discovery and characterization of a number of potent and selective small molecule inhibitors of the hepatitis C (HCV) NS3/4 protease. These molecules are part of InterMune's robust HCV protease inhibitor program and demonstrate promising potency, bioavailability and metabolic stability in preclinical models. The data were presented at the 55th Annual Meeting of the American Association for the Study of Liver Diseases (AASLD).

According to the Centers for Disease Control an estimated 3.9 million (1.8%) Americans have been infected with HCV, of whom 2.7 million are chronically infected, and the prevalence of chronic HCV is increasing. Currently available therapies are insufficient, creating a need for the development of novel therapeutic approaches. Protease inhibitors represent a promising class of drugs for HCV, and the HCV NS3/4 protease is an attractive drug target because of its involvement in viral replication and suppressive effects on host response to viral invasion.

InterMune and Array BioPharma scientists worked in collaboration to discover novel small molecule inhibitors of the HCV NS3/4 protease. Compounds were designed using computational modeling techniques and optimized to achieve high potency. Preclinical plasma pharmacokinetic analysis following intravenous and oral administration was then used in conjunction with other in vitro assays and stability studies to optimize the compounds.

"We have discovered highly potent, metabolically stable, orally available small molecule inhibitors of the HCV NS3/4 protease," said Lawrence Blatt, Ph.D., Senior Vice President of Preclinical and Applied Research at InterMune, who presented the data. "Our preclinical data provide us with the rationale to further test these compounds with the goal of selecting the most appropriate candidate to take into the clinic for development as a treatment for patients with HCV."

In addition, InterMune and Array BioPharma announced the extension of their collaboration, which has focused on the discovery and development of small molecule drugs directed against HCV since 2002. Under this extension, Array will perform process research and cGMP scale-up through Phase I clinical trials of drug candidates resulting from the program. In addition, Array will create second-generation compounds as back-up candidates for the program.

"We are very excited by the progress we have made advancing our novel small molecule program and as a result we have extended our collaboration with Array BioPharma. This extended agreement provides a valuable opportunity to continue the development of novel HCV inhibitors, which we believe may one day prove to be an important component of treatment for HCV patients," said Dan Welch, Chief Executive Officer and President of InterMune. "In addition to our protease inhibitor program, we are advancing our robust and late stage HCV pipeline and growing our marketed brand, Infergen (interferon alfacon-1) for HCV."

In September 2002, InterMune launched a drug discovery program with Array BioPharma to pursue small molecule therapeutics targeting HCV. Over the past two years, scientists from InterMune and Array have collaborated to design, create, optimize and evaluate drug candidates. In September 2004, InterMune entered into a nonexclusive licensing agreement with Chiron Corporation granting InterMune a license to discover, develop and commercialize small molecule therapeutic agents against certain HCV targets that Chiron currently holds under patent protection.

InterMune is a biopharmaceutical company that is committed to developing and commercializing innovative therapies in hepatology. In addition to the currently marketed product indicated for the treatment of chronic HCV (Infergen), InterMune has a broad and deep late-stage product portfolio addressing HCV, particularly in patients who are considered nonresponders to previous pegylated interferons plus ribavirin. Leading the hepatology portfolio is the DIRECT trial, an ongoing Phase III study of daily interferon alfacon-1 (Infergen) plus ribavirin, and an ongoing Phase II trial of daily interferon alfacon-1 plus interferon gamma-1b (Actimmune) with and without ribavirin. Both of these trials are for the treatment of HCV patients who do not respond to first-line therapy (pegylated interferon-alfa 2a or 2b plus ribavirin). In addition, InterMune has an early stage small molecule program targeted at the HCV protease.

Array BioPharma is a biopharmaceutical company focused on the discovery, development and commercialization of orally active drugs to address significant unmet medical needs. Array's proprietary drug development pipeline is primarily focused on the treatment of cancer and inflammatory disease and includes several small molecule drug candidates that are designed to regulate targets in therapeutically important biologic pathways. In addition, leading pharmaceutical and biotechnology companies access Array's drug discovery technologies and expertise through collaborations to design, create, optimize and evaluate drug candidates across a broad range of therapeutic areas.

InterMune, Inc.

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www.intermune.com

Array BioPharma, Inc.

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www.arraybiopharma.com