CHIR Chiron (MM)

Chiron Announces Update on Tezacitabine Program Company to Discontinue Development of Compound Based on Analysis of Phase II Results to Date EMERYVILLE, Calif., March 19 /PRNewswire-FirstCall/ -- Chiron Corporation today announced that the company has decided to discontinue further development of tezacitabine, a next-generation nucleoside analog, based on an analysis of the data from a Phase II trial in patients with gastroesophageal cancer. The compound did not demonstrate sufficient antitumor activity in the trial to satisfy Chiron's predetermined criteria to advance the program. The company had previously announced that it had concluded Phase II development of tezacitabine in patients with colorectal cancer. No safety issues were identified in treatment with tezacitabine. "Data from the Phase II trial failed to meet Chiron's threshold for moving the program forward," said Dr. Stephen Dilly, senior vice president of development, Chiron BioPharmaceuticals. "We had set explicit milestones for ourselves so that we could quickly and efficiently reach a conclusion about the program. We are now evaluating our options for the tezacitabine program. We remain focused on developing new treatments for cancer, including our programs for Proleukin(R) in combination with rituximab and for CHIR258, our growth factor kinase inhibitor." Chiron acquired tezacitabine in January 2002 with the purchase of Matrix Pharmaceutical. The side effect profile for tezacitabine is consistent with that of other nucleoside analogs, with fevers and clinically manageable reductions in white blood cell counts being the most commonly reported side effects. Chiron BioPharmaceuticals develops and manufactures high-value therapeutic products to treat cancer and infectious disease. The flagship of Chiron's oncology franchise is Proleukin(R) (aldesleukin) interleukin-2 for metastatic melanoma and metastatic renal cell cancer. Chiron is currently conducting a Phase II trial evaluating the potential benefit of Proleukin in combination with rituximab for the treatment of low-grade non-Hodgkin's lymphoma in patients who have previously failed rituximab treatment. A second Phase II trial, in rituximab-naive patients with low-grade non-Hodgkin's lymphoma, is expected to begin later in 2004. The company's first small molecule compound, CHIR258, entered Phase I testing in early 2004. Chiron expects to file an IND later this year for anti-CD40, a monoclonal antibody with the potential to target B-cell hematologic malignancies. About Chiron Chiron Corporation, headquartered in Emeryville, California, is a global pharmaceutical company that leverages a diverse business model to develop and commercialize high-value products that make a difference in people's lives. The company has a strategic focus on cancer and infectious disease. Chiron applies its advanced understanding of the biology of cancer and infectious disease to develop products from its platforms in proteins, small molecules and vaccines. The company commercializes its products through three business units: BioPharmaceuticals, Vaccines and Blood Testing. For more information about Chiron, visit the company's website at http://www.chiron.com/. This news release contains forward-looking statements, including statements regarding sales growth, product development initiatives and new product marketing, that involve risks and uncertainties and are subject to change. A discussion of Chiron's operations and financial prospects is contained in documents the company has filed with the SEC, including the form 10-K for the year ended December 31, 2003, and will be contained in subsequently periodic filings made with the SEC. These documents identify important factors that would cause the company's actual performance to differ from current expectations, including the outcomes of clinical trials, regulatory reviews and approvals, manufacturing capabilities, intellectual property protections and defenses, stock-price and interest-rate volatility, and marketingeffectiveness. In particular, there can be no assurance that Chiron will increase sales of existing products, successfully develop and receive approval to market new products, or achieve market acceptance for such new products. There can be no assurance that Chiron's out-licensing activities will generate significant revenue, nor that its in-licensing activities will fully protect it from claims of infringement by third parties. Consistent with SEC Regulation FD, we do not undertake an obligation to update the forward-looking information we are giving today. NOTE: Proleukin is a trademark of Chiron Corporation. DATASOURCE: Chiron Corporation CONTACT: media, Chiron Corporate Communications, +1-510-923-6500, or investors, Chiron Investor Relations, +1-510-923-2300 Web site: http://www.chiron.com/

Copyright