New England Journal of Medicine Publishes Data from Pivotal Phase 3 PROVENGE IMPACT Study

SEATTLE, July 28 /PRNewswire-FirstCall/ -- Dendreon Corporation (Nasdaq: DNDN) announced today the publication of data from the pivotal Phase 3 IMPACT study in the New England Journal of Medicine, showing that PROVENGE® (sipuleucel-T) demonstrated a statistically significant improvement in overall survival compared to control in men with asymptomatic or minimally symptomatic metastatic castration resistant prostate cancer (mCRPC). The manuscript is published in the July 29, 2010 issue of the journal.

PROVENGE is the first product in a new therapeutic class known as autologous cellular immunotherapies to be approved by the U.S. Food and Drug Administration for the treatment of asymptomatic or minimally symptomatic mCRPC.

The 512-patient multi-center, randomized, double-blind, placebo-controlled IMPACT (IMmunotherapy for Prostate AdenoCarcinoma Treatment) study demonstrated that PROVENGE extended median survival by 4.1 months compared to control (25.8 months vs. 21.7 months) and reduced the risk of death by 22.5% compared to control (HR=0.78; P=0.032). Adverse events more commonly reported in the PROVENGE arm in this study included chills, fever, headache, influenza-like illness, muscle aches, hypertension and groin pain.

"These results represent the beginning of a new era in the treatment of cancer, one in which a patient's own immune system is harnessed to fight the disease," said Philip Kantoff, M.D., lead author of the publication, co-principal investigator of IMPACT and Chief of the Division of Solid Tumor Oncology at the Dana-Farber Cancer Institute and Professor of Medicine at Harvard Medical School. "Furthermore, the magnitude of the survival benefit coupled with the side effect profile and short duration of therapy place PROVENGE as a new standard of care for men with asymptomatic or minimally symptomatic mCRPC."

Results of the published IMPACT study also showed that:

• The survival benefit associated with PROVENGE was observed consistently across multiple patient subgroups, including those with prognostic factors known to be adversely correlated with overall survival, such as PSA, LDH, alkaline phosphatase, number of bone metastasis, Gleason score, performance status, and presence of pain;
• Of patients that received PROVENGE, 97.1% received at least one infusion and 92.2% received all three infusions.  In addition, the median time from the first to the third infusion was 28 days;
• Sensitivity analyses provided no evidence that the use of docetaxel could account for the observed treatment difference with respect to overall survival;
• Results were consistent with and confirmed the findings of D9901, a Phase 3, randomized trial, in which the PROVENGE group had a median increase in survival of 4.5 months, a median survival of 25.9 months, and a 3-year survival rate of 34.1%;
• The time to objective disease progression was similar in the two study groups and consistent with results from other trials in this patient population; and
• Overall, 0.9% of patients in the PROVENGE group were unable to receive all three infusions because of infusion-related adverse events.

"PROVENGE has opened a new door in the treatment of advanced prostate cancer, providing patients with a clear and meaningful survival benefit, as well as a minimal and readily manageable side effect profile, with a short duration of therapy," said Paul Schellhammer, M.D., professor of urology at the Eastern Virginia Medical School and co-principal investigator of the IMPACT study.  

PROVENGE Safety

PROVENGE is intended solely for autologous use and is not routinely tested for transmissible infectious diseases.

The safety evaluation of PROVENGE was based on 601 prostate cancer patients in four randomized clinical trials who underwent at least one leukapheresis. The most common adverse events (incidence > to 15%) are chills, fatigue, fever, back pain, nausea, joint ache, and headache. Serious adverse events reported in the PROVENGE group include acute infusion reactions (occurring within 1 day of infusion) and cerebrovascular events. In controlled clinical trials, severe (Grade 3) acute infusion reactions were reported in 3.5% of patients in the PROVENGE group. Reactions included chills, fever, fatigue, asthenia, dyspnea, hypoxia, bronchospasm, dizziness, headache, hypertension, muscle ache, nausea, and vomiting. No Grade 4 or 5 acute infusion reactions were reported in patients in the PROVENGE group.

To fulfill a post marketing requirement and as a part of the company's ongoing commitment to patients, Dendreon will conduct a registry of approximately 1500 patients to further evaluate a small potential safety signal of cerebrovascular events. In four randomized clinical trials of PROVENGE in prostate cancer patients, cerebrovascular events were observed in 3.5% of patients in the PROVENGE group compared with 2.6% of patients in the control group.

For more information on PROVENGE, please see the full prescribing information or call Dendreon ON CALL at 1-877-336-3736.

About Active Cellular Immunotherapy

PROVENGE is classified by the FDA as an autologous cellular immunotherapy.  It is designed to be an active cellular immunotherapy.  Active cellular immunotherapy is designed to stimulate a T-cell response to cancer cells.  An immune response is started by a specialized class of immune system cells called antigen-presenting cells (APCs). APCs take up antigen from their surroundings and process the antigen into fragments that are then displayed on the APC surface. Once displayed, these antigens can be recognized by specific classes of immune cells called T lymphocytes (T-cells), which are activated as a result of their engagement with APCs and combat disease by seeking antigen-bearing cells directly. PROVENGE is designed to target the prostate cancer antigen prostatic acid phosphatase (PAP), an antigen that is expressed in more than 95 percent of all prostate cancers.

About Prostate Cancer

According to the American Cancer Society, prostate cancer is the most common non-skin cancer in the United States and the third most common cancer worldwide. More than two million men in the United States have prostate cancer, with an estimated 217,730 new cases and approximately 32,050 men expected to die from the disease in 2010.

About Dendreon

Dendreon Corporation is a biotechnology company whose mission is to target cancer and transform lives through the discovery, development and commercialization of novel therapeutics. The Company applies its expertise in antigen identification, engineering and cell processing to produce active cellular immunotherapy product candidates designed to stimulate an immune response. Dendreon is also developing an orally-available small molecule that targets TRPM8 that could be applicable to multiple types of cancer. The Company is headquartered in Seattle, Washington and has manufacturing facilities in New Jersey, Georgia and California. Dendreon is traded on the Nasdaq Global Market under the symbol DNDN. For more information about the Company and its programs, visit http://www.dendreon.com/.

www.dendreon.com

This news release contains forward-looking statements that are subject to risks and uncertainties. Factors that could affect these forward-looking statements include, but are not limited to, developments affecting Dendreon's business and prospects, including commercialization of PROVENGE. Information on the factors and risks that could affect Dendreon's business, financial condition and results of operations are contained in Dendreon's public disclosure filings with the U.S. Securities and Exchange Commission, which are available at www.sec.gov. Dendreon cautions investors not to place undue reliance on the forward-looking statements contained in this press release. All forward-looking statements are based on information currently available to Dendreon on the date hereof, and Dendreon undertakes no obligation to revise or update these forward-looking statements to reflect events or circumstances after the date of this press release, except as required by law.

SOURCE Dendreon Corporation