Sunesis' Voreloxin Receives FDA Orphan Drug Designation for Acute Myeloid Leukemia

Sunesis' Voreloxin Receives FDA Orphan Drug Designation for Acute Myeloid
Leukemia

SOUTH SAN FRANCISCO, Calif., Nov. 5 /PRNewswire-FirstCall/ -- Sunesis
Pharmaceuticals, Inc. (Nasdaq: SNSS) today announced that the U.S. Food and
Drug Administration has granted voreloxin orphan drug designation for the
treatment of acute myeloid leukemia (AML). Sunesis is currently conducting two
Phase 2 clinical trials of voreloxin in AML: a single-agent study, known as
REVEAL-1, of voreloxin in newly diagnosed elderly AML patients unlikely to
benefit from standard induction chemotherapy and a study evaluating voreloxin
in combination with cytarabine in relapsed/refractory AML.

"This designation recognizes the acute need for more options in treating this
poor-prognosis disease," stated Steven B. Ketchum, Ph.D., Senior Vice
President of Research and Development at Sunesis. "We believe voreloxin has
the potential to impact the standard of care for AML and we continue to be
encouraged by our progress. We are finalizing a registration strategy for
voreloxin in AML and anticipate launching a pivotal trial in 2010."

Orphan drug designation is granted by the FDA Office of Orphan Drug Products
to novel drugs or biologics that treat a rare disease or condition affecting
fewer than 200,000 patients in the U.S. The designation provides eligibility
for a seven-year period of market exclusivity in the United States after
product approval and an exemption from user fees.

About Voreloxin

Voreloxin is a first-in-class anticancer quinolone derivative, or AQD, a class
of compounds that has not been used previously for the treatment of cancer.
Voreloxin both intercalates DNA and inhibits topoisomerase II, resulting in
replication-dependent, site-selective DNA damage, G2 arrest and apoptosis.
Voreloxin is currently being evaluated in a Phase 2 clinical trial (known as
the REVEAL-1 trial) in previously untreated elderly AML patients and in a
Phase 1b/2 clinical trial combining voreloxin with cytarabine for the
treatment of patients with relapsed/refractory AML, as well as in an ongoing
Phase 2 single-agent trial in platinum-resistant ovarian cancer.

About Acute Myeloid Leukemia

AML is a rapidly progressing cancer of the blood characterized by the
uncontrolled proliferation of immature blast cells in the bone marrow. The
Leukemia and Lymphoma Society estimates that nearly 13,000 new cases of AML
will be diagnosed and approximately 9,000 deaths from AML will occur in the
U.S. in 2009. AML is generally a disease of older adults, and the median age
of a patient diagnosed with AML is about 67 years. A majority of elderly
patients are not considered candidates for standard induction therapy or
decline therapy, resulting in an acute need for new treatment options.

About Sunesis Pharmaceuticals

Sunesis is a 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,
voreloxin, 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 logo are trademarks of Sunesis Pharmaceuticals, Inc.

This press release contains forward-looking statements, including without
limitation statements related to the potential efficacy and commercial
potential of voreloxin and Sunesis' plans to launch a pivotal trial of
voreloxin including the timing thereof. Words such as "believe," "potential,"
"anticipate," 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 additional funding, the risk that Sunesis' drug development
activities for voreloxin could be halted significantly or delayed for various
reasons, the risk that Sunesis' clinical trials for voreloxin may not
demonstrate safety or efficacy or lead to regulatory approval, the risk that
preliminary data and trends may not be predictive of future data or results,
the risk that Sunesis' nonclinical studies and clinical trials may not satisfy
the requirements of the FDA or other regulatory agencies, risks related to the
conduct of Sunesis' clinical trials, risks related to the manufacturing of
voreloxin, and the risk that Sunesis' proprietary rights may not adequately
protect voreloxin. These and other risk factors are discussed under "Risk
Factors" and elsewhere in Sunesis' Quarterly Report on Form 10-Q for the
quarter ended June 30, 2009 and 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 the company's expectations with
regard thereto or any change in events, conditions or circumstances on which
any such statements are based.

Investor and Media Inquiries:
Andrea Rabney Eric Bjerkholt
Argot Partners Sunesis Pharmaceuticals
212-600-1902 650-266-3717

SOURCE Sunesis Pharmaceuticals, Inc.

Andrea Rabney of Argot Partners, +1-212-600-1902; or Eric Bjerkholt of Sunesis
Pharmaceuticals, +1-650-266-3717