ZymoGenetics Reports Favorable Survival Data from IL-21 Phase 2a Clinical Trial in Melanoma

Median overall survival of 12.4 months
SEATTLE, Sep 29, 2010 (BUSINESS WIRE) --

ZymoGenetics, Inc. (NASDAQ:ZGEN) today announced positive survival data from a Phase 2a clinical trial in metastatic melanoma with recombinant Interleukin 21 (IL-21) as a single agent. Median overall survival was 12.4 months, and the percentage of patients surviving at 12 months was 53%.

"The median overall survival of 12.4 months in the Phase 2 study with IL-21 in advanced melanoma patients is very encouraging," said Eleanor L. Ramos, M.D., Senior Vice President and Chief Medical Officer of ZymoGenetics. "We look forward to further results from an ongoing IL-21 Phase 2b randomized clinical trial in melanoma."

The open-label, single-arm, multi-center Phase 2 study was conducted by the NCIC Clinical Trials Group in Canada. A total of 40 patients with Stage 4 melanoma were enrolled and treated with IL-21 using 3 dosing regimens. Previous results for the clinical trial were presented at the American Society of Clinical Oncology 2010 meeting. Overall response rate was 23% in 39 evaluable patients, and median progression-free survival was 4.3 months. Common adverse events were fatigue, rash, fever, myalgia, anorexia, chills and nausea. Responses were not dependent on B-Raf status.

About Interleukin 21 (IL-21)

Interleukin 21 (IL-21) is a cytokine that modifies the function of cells in the immune system. IL-21 activates several types of immune cells thought to be critical in eliminating cancerous or virally infected cells from the body. Specifically, IL-21 enhances the activity of natural killer cells and has multiple effects on cytotoxic T cells. This novel immunotherapy has demonstrated antitumor activity in multiple tumor types (metastatic melanoma, renal cell cancer and non-Hodgkin's lymphoma) as a single agent and in combination with other therapies. More than 250 patients have been treated with IL-21 in clinical trials. The lead indication is metastatic melanoma, where IL-21 has shown efficacy.

About the NCIC Clinical Trials Group

The NCIC Clinical Trials Group (NCIC CTG) is a cancer clinical trials cooperative group that conducts phase I-III trials testing anti-cancer and supportive therapies across Canada and internationally. It is one of the national programmes and networks of the Canadian Cancer Society Research Institute (CCSRI), and is supported by the CCSRI with funds raised by the Canadian Cancer Society (CCS). The NCIC CTG's Central Office is located at Queen's University in Kingston, Ontario, Canada.

About ZymoGenetics

ZymoGenetics is a biopharmaceutical company focused on the development and commercialization of therapeutic proteins for the treatment of human diseases. The company developed and is marketing RECOTHROM(R) Thrombin, topical (Recombinant) in the United States. ZymoGenetics has two product candidates in Phase 2 clinical development: PEG-Interferon lambda, being studied in collaboration with Bristol-Myers Squibb for treatment of hepatitis C virus infection, and IL-21, being tested as a potential treatment for metastatic melanoma. In addition, ZymoGenetics has an anti-IL-31 monoclonal antibody in preclinical development, which it expects to test initially as a treatment for atopic dermatitis. Several of the product candidates previously identified through ZymoGenetics' discovery research efforts have been licensed to and are being developed by third parties, including Merck Serono and Novo Nordisk. ZymoGenetics is eligible to receive milestone payments and royalties related to these assets. For further information, visit www.zymogenetics.com.