Onyx Pharmaceuticals Announces a Teleconference and Webcast to Provide an Update on Nexavar

EMERYVILLE, Calif. — Dec. 04, 2006

Onyx Pharmaceuticals, Inc. (Nasdaq: ONXX) today announced that it will host a conference call today, Monday, December 4, 2006, at 10:00 a.m. Eastern Time (7:00 a.m. Pacific Time) to provide an update on Nexavar® (sorafenib) tablets.

Interested parties may access the live presentation at:
http://audioevent.mshow.com/314894/

or by dialing 706-758-9355 and using the passcode 2983873. A replay of the presentation will be available on the Onyx website or by dialing 706-645-9291 and using the passcode 2983873 approximately one hour after the teleconference concludes. The replay will be available through January 4, 2007.

Onyx Pharmaceuticals, Inc. is a biopharmaceutical company developing innovative therapies that target the molecular mechanisms that cause cancer. The company is developing Nexavar, a small molecule drug, with Bayer Pharmaceuticals Corporation. Nexavar has been approved for the treatment of advanced kidney cancer. For more information about Onyx’s pipeline and activities, visit the company’s web site at: www.onyx-pharm.com.

Nexavar® (sorafenib) tablets is a registered trademark of Bayer Pharmaceuticals Corporation.

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