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Steve Karlson
Windspeed Ventures
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Sunesis Pharmaceuticals, Inc. Files Registration Statement for Proposed Initial Public Offering

South San Francisco, CA, December 23, 2004 - Sunesis Pharmaceuticals, Inc. announced today that it has filed a registration statement with the Securities and Exchange Commission relating to the proposed initial public offering of its common stock. All of the shares of common stock will be offered by the Company.

Lehman Brothers Inc. and SG Cowen & Co., LLC are acting as joint book-running managers for this offering, and Needham & Company, Inc. is acting as co-manager. The number of shares to be offered and the price range for the offering have not yet been determined.

This offering will be made only by means of a prospectus. A copy of the preliminary prospectus may be obtained, when available, from either Lehman Brothers Inc., c/o ADP Financial Services, Prospectus Fulfillment, 1155 Long Island Avenue, Edgewood, NY 11717 or by fax at (631) 254-7268 or email request to sabrina_neat@adp.com or monica_castillo@adp.com or from SG Cowen & Co., LLC Prospectus Department, 1221 Avenue of the Americas, 6th Floor, New York, NY 10020.

A registration statement relating to these securities has been filed with the Securities and Exchange Commission but has not yet become effective. These securities may not be sold nor may offers to buy be accepted prior to the time the registration statement becomes effective. This press release shall not constitute an offer to sell or a solicitation of an offer to buy, nor shall there be any sale of these securities in any state or jurisdiction in which such an offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction.

About Sunesis Pharmaceuticals
Sunesis is a clinical-stage biopharmaceutical company focused on the discovery, development and commercialization of small molecule therapeutics for oncology, inflammatory diseases and other unmet medical needs. Sunesis has built a product candidate portfolio through internal discovery and the in-licensing of novel cancer therapeutics. The Company is advancing its product candidates through in-house research and development efforts and strategic collaborations with leading pharmaceutical and biopharmaceutical companies. For further information, visit www.sunesis.com.