Onyx Pharmaceuticals Announces First Quarter 2010 Financial Results Teleconference and Webcast

Emeryville, CA. — Apr. 27, 2010

Onyx Pharmaceuticals, Inc. (Nasdaq: ONXX) today announced that it will host a webcast and teleconference with management to provide a general business overview, as well as to discuss first quarter 2010 financial results, on Tuesday, May 4, 2010, at 5:00 p.m. Eastern Time (2:00 p.m. Pacific Time). Financial results for the first quarter ended March 31, 2021 will be released earlier that day.

Interested parties may access a live webcast of the presentation on the company’s website at:
http://www.onyx-pharm.com/view.cfm/32/Event-Calendar

or by dialing 847-619-6547 and using the passcode 26940268. A replay of the presentation will be available on the Onyx website or by dialing 630-652-3044 and using the passcode 26940268 approximately one hour after the teleconference concludes. The replay will be available through May 18, 2010.

About Onyx Pharmaceuticals, Inc.
Onyx Pharmaceuticals, Inc. is a biopharmaceutical company committed to improving the lives of people with cancer. The company, in collaboration with Bayer HealthCare Pharmaceuticals, Inc., is developing and marketing Nexavar® (sorafenib) tablets, a small molecule drug that is currently approved for the treatment of liver cancer and advanced kidney cancer. Additionally, Nexavar is being investigated in several ongoing trials in a variety of tumor types. Beyond Nexavar, Onyx has established a development pipeline of anticancer compounds at various stages of clinical testing, including carfilzomib, a next-generation proteasome inhibitor, that is currently being evaluated in multiple clinical trials for the treatment of patients with relapsed or relapsed/refractory multiple myeloma and solid tumors, and ONX 0801, a targeted alpha-folate inhibitor, currently in Phase 1 testing. For more information about Onyx, visit the company’s website at www.onyx-pharm.com.
Nexavar® (sorafenib) tablets is a registered trademark of Bayer HealthCare Pharmaceuticals, Inc.

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