PRESS RELEASE: Novacea Halts Late-Stage Trial of Prostate Cancer Drug Asentar

Novacea Halts Late-Stage Trial of Prostate Cancer Drug Asentar

SOUTH SAN FRANCISCO, CA - Nov 5, 2007 -- Novacea announced today that the company has ended its Phase 3 ASCENT-2 clinical trial of Asentar(TM) (DN-101), the company's lead investigational cancer therapy for the treatment of patients with androgen-independent prostate cancer, or AIPC, due to an imbalance of deaths between the two treatment arms, as observed by the Data Safety Monitoring Board (DSMB) for the clinical study.

The company and its partner, Schering-Plough, plan to fully analyze the clinical data to attempt to understand the cause of the higher death rate in the Asentar plus Taxotere® (docetaxel) treatment group. The study was comparing the benefits of weekly Asentar plus Taxotere to the current standard of care in the treatment of AIPC. To date, more than 900 of the planned total of 1,200 patients were enrolled in this study at multiple centers in various countries, including the United States, Canada, Germany, and Central Europe.

"The safety of the patients in our trials is our top concern. As such, Novacea and Schering-Plough have decided to end the ASCENT-2 trial, however, the product development alliance will continue," said John P. Walker, chief executive officer of Novacea. "The findings in ASCENT-2 are extremely surprising and disappointing to us, given the promising clinical activity that we observed in our Phase 2 ASCENT trial. Importantly, preliminary analysis has not identified any unexpected safety findings with Asentar. Over the next few months, we plan to further analyze the data, and discuss the findings with ASCENT-2 principal investigators and with prostate cancer experts to attempt to determine the possible causes for this outcome. We have informed all relevant constituents, most importantly the clinical trial sites treating patients and the regulatory authorities, and have suspended enrollment in other ongoing or planned trials in other indications until we have had a chance to assess the data more completely," said Mr. Walker. "Novacea remains committed to helping cancer patients, as we continue to advance our other clinical programs with AQ4N, our hypoxia-activated prodrug product candidate."

About Asentar

Asentar is an investigational new drug that is an oral, intermittent, high-dose of calcitriol, the most potent natural ligand or activator of the calcitriol receptor (also known as the vitamin D receptor). The Phase 3 ASCENT-2 study design was based on published results from a double-blinded, placebo-controlled, randomized, multi-site Phase 2 trial of Asentar plus Taxotere as compared to placebo plus Taxotere in AIPC.

Conference Call Information

Members of Novacea's management team will discuss the DSMB decision via a conference call today at 8:30 am Eastern Time. To participate in this conference call, please call 800-573-4842 (United States and Canada) or 617-224-4327 (International); passcode 10312122. The replay will also be available until Nov. 12, 2007 at 888-286-8010 (United States and Canada) or 617-801-6888 (International); passcode 47868709.

About Novacea

Novacea, Inc. is a biopharmaceutical company focused on in-licensing, developing and commercializing novel cancer therapies. Novacea has two product candidates in clinical trials, including Asentar(TM), which has been in a Phase 3 clinical trial for androgen-independent prostate cancer, or AIPC, and in a Phase 2 trial for advanced pancreatic cancer. Asentar is part of a development and commercialization agreement with Schering-Plough Corporation. Novacea's second product candidate, AQ4N, is a hypoxia-activated prodrug that is currently in a Phase 1b/2a clinical trial in glioblastoma multiforme and a Phase 2 trial for refractory acute lymphoblastic leukemia. More information on any of Novacea's trials can be found at

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