| Michael E. Tenta (650) 843-5636 mtenta@cooley.com | VIA EDGAR |
August 24, 2010
Securities and Exchange Commission
| Attention: | Jim B. Rosenberg Joel Parker Vanessa Robertson Suzanne Hayes Karen Ubell |
100 F Street, N.E.
Washington, D.C. 20549
Washington, D.C. 20549
| Re: | Onyx Pharmaceuticals, Inc. Form 10-K for Fiscal Year Ended December 31, 2009 Filed February 23, 2010 Definitive Proxy Statement filed April 9, 2010 File No. 000-28928 |
Ladies and Gentlemen:
On behalf of Onyx Pharmaceuticals, Inc. (the “Company”), this letter is being submitted in response to comments received from the staff of the Commission (the “Staff”) by letter dated August 17, 2010, with respect to the Company’s Form 10-K for Fiscal Year Ended December 31, 2009 and Definitive Proxy Statement filed April 9, 2010.
Please be advised that the Company currently expects that it will provide its response to the Staff’s comment letter on or before September 15, 2010 and will further advise the Staff if it becomes unable to do so.
Please do not hesitate to contact me at (650) 843-5636 if you have any questions or would like any additional information regarding this matter.
| Sincerely, | ||||
| /s/ Michael E. Tenta | ||||
| Michael E. Tenta | ||||
| cc: | Matthew K. Fust Executive Vice President and Chief Financial Officer |