OncoGenex initiates Phase 3 Prostate Cancer SATURN Trial

OncoGenex Pharmaceuticals, Inc. (NASDAQ: OGXI) announced today the initiation of a Phase 3 registration trial of custirsen sodium (OGX-011/TV-1011), its lead product candidate being developed for the treatment of castrate-resistant prostate cancer (CRPC). This trial, referred to as the Prostate Cancer SATURN Trial, is the first of three Phase 3 trials to be initiated under a global collaboration and license agreement between OncoGenex and Teva Pharmaceutical Industries (NASDAQ: TEVA) to develop and commercialize OGX-011/ TV-1011.

This randomized, controlled, international Phase 3 trial will be conducted in approximately 50 cancer centers and will enroll approximately 300 men with metastatic CRPC who have previously responded to first-line docetaxel therapy, but subsequently have disease progression that involves prostate cancer-related pain despite opioid usage. Patients will be randomized to receive retreatment with docetaxel/prednisone plus OGX-011/ TV-1011 or docetaxel/prednisone plus placebo in a blinded manner. The primary endpoint of the SATURN trial will be to determine whether durable pain palliation for 12 weeks or more is observed in a greater proportion of patients treated with docetaxel/prednisone plus OGX-011/ TV-1011 compared to docetaxel/prednisone plus placebo.

More information on the Prostate Cancer SATURN Trial is available on the Company's website at http://oncogenex.com/clinicalTrials/index.html.

The Principal Investigators for the SATURN trial are Dr. Tomasz Beer at the Oregon Health & Science University Knight Cancer Institute for the United States, Dr. Sebastien Hotte at Juravinski Cancer Centre in Hamilton, Ontario for Canada and Professor Karim Fizazi at the University of Paris for Europe. An Investigator meeting was held in May to train and initiate US and Canadian sites. The Company expects to initiate European sites in the third quarter of 2010.

The SATURN trial design is based on the Phase 2 data in patients with metastatic CRPC who were treated with OGX-011/ TV-1011 in combination with docetaxel/prednisone retreatment as second-line chemotherapy.

"Pain is a dominant symptom in patients with progressive prostate cancer and frequently remains a challenge despite treatment with opioid analgesics. Poorly controlled pain has devastating effects on both patients and their family members," stated Dr. Beer. "In the Phase 2 trial, almost half of patients who had pain or were on opioids and were retreated with docetaxel/prednisone with the addition of OGX-011/ TV-1011 had durable pain palliation for 12 weeks or more. This is better than expected based on pain responses seen after initial treatment with docetaxel/prednisone."

A separate Phase 2 trial evaluating OGX-011/ TV-1011 in combination with first-line chemotherapy showed that patients with advanced metastatic prostate cancer who were treated with OGX-011/ TV-1011 plus docetaxel had a median overall survival of 23.8 months compared to 16.9 months for patients treated with docetaxel alone -- a 6.9 month observed survival advantage for the OGX-011/ TV-1011 arm.

OGX-011/ TV-1011 has received Fast Track designation from the U.S. Food and Drug Administration (FDA) and this SATURN trial is being conducted through the Special Protocol Assessment (SPA) process. Earlier this year, the European Medicines Agency indicated that the Committee for Medicinal Products for Human Use was in overall agreement with the company's development plan for OGX-011/ TV-1011 which included this Phase 3 trial.

In 2009, Teva Pharmaceutical Industries Ltd. and OncoGenex Pharmaceuticals, Inc. entered into a global license and collaboration agreement to develop and commercialize OGX-011/TV-1011. In addition to the ongoing SATURN trial assessing durable pain palliation as the primary endpoint for second-line chemotherapy in men with metastatic CRPC, the global Phase 3 clinical program also includes a Phase 3 trial in first-line chemotherapy for metastatic CRPC which assesses survival as the primary endpoint. A Phase 3 trial assessing survival as the primary endpoint in first-line treatment of advanced, unresectable non-small cell lung cancer (NSCLC) is also planned as part of the strategy to develop and commercialize OGX-011/TV-1011.