Investor and Media Inquiries: David Pitts Argot Partners 212-600-1902 Eric Bjerkholt Sunesis Pharmaceuticals Inc. 650-266-3717 Sunesis Pharmaceuticals Reports Fourth Quarter and Full-Year 2013 Financial Results and Recen

Sunesis Pharmaceuticals Reports Fourth Quarter and Full-Year 2013 Financial Results and Recent Highlights

Phase 1b/2 Data from MD Anderson Sponsored Study of Vosaroxin in AML and

High-Risk MDS to be Presented at the AACR Annual Meeting 2014

Sunesis to Host Conference Call Today at 11:00AM Eastern Time

SOUTH SAN FRANCISCO, Calif., (March 6, 2014) Sunesis Pharmaceuticals, Inc. (NASDAQ: SNSS) today reported financial results for the fourth

quarter and year ended December 31, 2013. Loss from operations for the three months and year ended December 31, 2013 was $7.6 million and $31.8 million, respectively. As of December 31, 2013, cash, cash equivalents and marketable

securities totaled $39.3 million. On March 4, 2014, Sunesis closed an underwritten public offering for net proceeds of approximately $40.0 million.

Sunesis also announced today that updated data from the ongoing Phase 1b/2 University of Texas MD Anderson Cancer Center-sponsored study of vosaroxin in

combination with decitabine in older patients with previously untreated acute myeloid leukemia (AML) and high-risk myelodysplastic syndrome (MDS) will be presented at the American Association for Cancer Research Annual Meeting 2014 (AACR) on

April 8 in San Diego, California. The abstract (#CT307), which includes preliminary results, can be found on the AACR website.

Vosaroxin is one of the most advanced and promising therapies in development for AML today, and with a transformative year ahead, we will look to

realize its ability to change the global standard of care in this disease, said Daniel Swisher, Chief Executive Officer of Sunesis. This goal centers on the unblinding of VALOR, expected in the third quarter of 2014, and will be

supported by data from investigator- and company-sponsored trials, beginning with the MD Anderson-sponsored Phase 1b/2 study presentation at AACR in April. A positive VALOR data readout will begin Sunesis transition from a development-stage to

a commercial-ready company.

Mr. Swisher added: Beyond our lead program, 2014 has and will continue to be an important year for the

development of our pipeline. We recently announced the licensing of two exciting new programs - a differentiated BTK inhibitor and a novel PDK1 inhibitor program. Together with vosaroxin and MLN2480, a pan-RAF inhibitor being developed with

Millennium, these assets provide the foundation for creating a leading oncology franchise.

Fourth Quarter 2013 and Recent Highlights

In October 2013, Sunesis announced the initiation of a Phase 1/2 investigator-sponsored trial of vosaroxin in adult patients with previously

treated intermediate-2 or high-risk MDS. The trial is being conducted at Weill Cornell Medical College and New York-Presbyterian Hospital under the direction of Gail J. Roboz, M.D., Associate Professor of Medicine and Director of the Leukemia

The second agreement, with Millennium: The Takeda Oncology Company,

is for global commercial rights to several potential first-in class, pre-clinical inhibitors of the novel target PDK1 (phosphoinositide-dependent kinase-1). PDK1 is a key kinase and mediator of PI3K/AKT signaling, a pathway involved in cell growth,

proliferation, differentiation, motility and survival. Sunesis anticipates selecting a lead PDK1 development candidate this year to take into IND-enabling studies.

Financial Highlights

The warrants may only be gross exercised for cash following unblinding of the VALOR trial. The per share exercise price of

the first warrant (Series A warrants) is $8.50 and the second warrant (Series B warrants) is $12.00. The Series A warrants are exercisable until the later of 30 days after VALOR unblinding (but no later than March 4, 2016) or December 4,

2014. The Series B warrants are exercisable until the later of 30 days following the PDUFA date for vosaroxin (but no later than March 4, 2016) or September 4, 2015. Assuming the warrants are exercised in full, the warrants could result in

additional net proceeds to Sunesis of up to $95.3 million.

AACR Poster Information

A poster, titled Phase

I/II study of vosaroxin and decitabine in older patients with acute myeloid leukemia (AML) and high risk myelodysplastic syndrome (MDS), will be presented at the San Diego Convention Center, Hall A-E, Poster Section 38, during the Phase

II/III Clinical Trials Poster Session on Tuesday, April 8, 2014 from 8:00 a.m. to 12:00 p.m. Pacific Time (Poster #7).

Sunesis will host an update conference call today, March 6th at 11:00 a.m. Eastern Time. The call can be accessed by dialing

(800) 591-6942 (U.S. and Canada) or (617) 614-4909 (international), and entering passcode 15910310. To access the live audio webcast, or the subsequent archived recording, visit the Investors and Media - Calendar of Events

section of the Sunesis website at www.sunesis.com. The webcast will be recorded and available for replay on the company s website for two weeks.

VALOR is a Phase 3, randomized,

double-blind, placebo-controlled, pivotal trial in patients with first relapsed or refractory AML. The trial enrolled 712 patients at more than 100 leading sites in the U.S., Canada, Europe, Australia, New Zealand and South Korea. Patients were

randomized in a ratio of 1:1 to receive either vosaroxin on days one and four in combination with cytarabine daily for five days, or placebo in combination with cytarabine. The trial s primary endpoint is overall survival. For more information

on the VALOR trial, please visit www.valortrial.com.

Vosaroxin is a first-in-class anti-cancer quinolone derivative (AQD), a class of compounds that has not been used previously for the treatment of cancer.

Vosaroxin both intercalates DNA and inhibits topoisomerase II, resulting in replication-dependent, site-selective DNA damage, G2 arrest and apoptosis. Both the FDA and European Commission have granted orphan drug designation to vosaroxin for the

treatment of AML. Additionally, vosaroxin has been granted fast track designation by the FDA for the potential treatment of relapsed or refractory AML in combination with cytarabine.

AML is a rapidly progressing cancer of the blood characterized by the uncontrolled proliferation of immature blast cells in the bone marrow. The American

Cancer Society estimates there will be approximately 18,860 new cases of AML and approximately 10,460 deaths from AML in the U.S. in 2014. Additionally, it is estimated that the prevalence of AML across major global markets (U.S., France, Germany,

Italy, Spain, United Kingdom and Japan) is over 50,000. AML is generally a disease of older adults, and the median age of a patient diagnosed with AML is about 67 years. AML patients with relapsed or refractory disease and newly diagnosed AML

patients over 60 years of age with poor prognostic risk factors typically die within one year, resulting in an acute need for new treatment options for these patients.

About Sunesis Pharmaceuticals

biopharmaceutical company focused on the development and commercialization of new oncology therapeutics for the treatment of solid and hematologic cancers. Sunesis has built a highly experienced cancer drug development organization committed to

advancing its lead product candidate, vosaroxin, in multiple indications to improve the lives of people with cancer. For additional information on Sunesis, please visit http://www.sunesis.com.

SUNESIS and the logos are trademarks of Sunesis Pharmaceuticals, Inc.

This press release contains forward-looking statements, including statements related to Sunesis s overall strategy, the design, conduct, progress, timing

and results of the VALOR trial and Sunesis other clinical trials, the sufficiency of Sunesis financial resources and the commercial potential for vosaroxin. Words such as anticipate, approximately,

assume, believe, could, potential, promising, realize, well beyond, and similar expressions are intended to identify forward-looking statements. These

forward-looking statements are based upon Sunesis current expectations. Forward-looking statements involve risks and uncertainties. Sunesis actual results and the timing of events could differ materially from those anticipated in such

forward-looking statements as a result of these risks and uncertainties, which include, without limitation, risks related to Sunesis need for substantial additional funding to complete the development and commercialization of vosaroxin, risks

related to whether outstanding warrants will be exercised in the future, risks related to Sunesis ability to raise the capital that it believes to be accessible and is required to fully finance the development and commercialization of

vosaroxin, the risk that raising funds through lending arrangements may restrict our operations or produce other adverse results, the risk that Sunesis development activities for vosaroxin could be otherwise halted or significantly delayed for

various reasons, the risk that Sunesis clinical studies for vosaroxin may not demonstrate safety or efficacy or lead to regulatory approval, the risk that data to date and trends may not be predictive of future data or results, the risk that

Sunesis nonclinical studies and clinical studies may not satisfy the requirements of the FDA, European Commission or other regulatory agencies, risks related to the conduct of Sunesis clinical trials, risks related to the manufacturing

of vosaroxin and supply of the active pharmaceutical ingredients required for the conduct of Sunesis clinical trials, the risk of third party opposition to granted patents related to vosaroxin, and the risk that Sunesis proprietary

rights may not adequately protect vosaroxin. These and other risk factors are discussed under Risk Factors and elsewhere in Sunesis Quarterly Report on Form 10-Q for the quarter ended September 30, 2013, Sunesis Annual

Report on Form 10-K for the year ended December 31, 2013, when available, and Sunesis other filings with the Securities and Exchange Commission. Sunesis expressly disclaims any obligation or undertaking to release publicly any updates or

revisions to any forward-looking statements contained herein to reflect any change in Sunesis expectations with regard thereto or any change in events, conditions or circumstances on which any such statements are based.

SUNESIS PHARMACEUTICALS, INC.

CONSOLIDATED BALANCE SHEETS

Note 1: The consolidated balance sheet as of December 31, 2012 has been derived from the audited financial statements as

of that date included in the Company s Annual Report on Form 10-K for the year ended December 31, 2012.

SUNESIS PHARMACEUTICALS, INC.

CONSOLIDATED STATEMENTS OF OPERATIONS

AND COMPREHENSIVE (LOSS) INCOME

(In thousands, except per share amounts)