Sunesis Announces New Data on Voreloxin for Acute Myeloid Leukemia To Be Presented at ASH

12-02-2008

Sunesis Pharmaceuticals, Inc. (Nasdaq: SNSS), a biopharmaceutical company focused on the development and commercialization of new oncology therapeutics, today announced new data from its studies of voreloxin in acute myeloid leukemia (AML) will be presented during the 50th American Society of Hematology (ASH) Annual Meeting in San Francisco, California, December 5-9, 2008. Researchers will present updated interim data from the company's ongoing Phase 2 clinical trial of single-agent voreloxin (formerly SNS-595) for elderly patients with newly diagnosed AML and from its Phase 1b/2 study of voreloxin in combination with cytarabine for relapsed/refractory AML. In addition, results from the Phase 1 study of SNS-032, a selective inhibitor of cyclin dependent kinases 2, 7 and 9, in both chronic lymphocytic leukemia and multiple myeloma will be presented. Following are the details on each of these data presentations.

Sunday, December 7, 2008

Viewing: 9:00 a.m. to 8:00 p.m. PT

Presentation Time: 6:00 p.m. to 8:00 p.m. PT

Hall A, MosconeCenter

Abstract #1951

Title: "Phase 2 Study of Voreloxin (Formerly Known as SNS-595) as Single Agent Therapy for Elderly Patients with Newly Diagnosed Acute Myeloid Leukemia (AML): Preliminary Safety and Clinical Responses (The REVEAL-1 Study)"

Poster Board II-45

Abstract #1955

Title: "Voreloxin (formerly known as SNS-595) in Combination with Cytarabine Demonstrates Preliminary Clinical Responses in a Phase 1 Study in Relapsed/Refractory Acute Myeloid Leukemia"

Poster Board II-49

Monday, December 8, 2008

Viewing: 10:30 a.m. to 7:30 p.m. PT

Presentation Time: 5:30 p.m. to 7:30 p.m. PT

Hall A, MosconeCenter

Abstract #3178

Title: "A Phase 1 Trial of SNS-032, a Potent and Specific CDK 2, 7 and 9 Inhibitor, in Chronic Lymphocytic Leukemia and Multiple Myeloma"

Poster Board III-260

Conference Call Information

Sunesis management will host a conference call to discuss the voreloxin and SNS-032 clinical data presented at the ASH Annual Meeting on Tuesday, December 9, 2008, at 11:00 a.m. ET / 8:00 a.m. PT. Individual and institutional investors can access the call via 1-877-856-1956 (U.S. and Canada) or +1-719-325-4805 (international). 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 until December 23, 2008.

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 over 13,000 new cases of AML were diagnosed and approximately 9,000 deaths from AML occurred in the U.S. during 2007. 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 Voreloxin

Voreloxin (formerly SNS-595), is a novel naphthyridine analog, structurally related to quinolones, 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, irreversible G2 arrest and apoptosis. Voreloxin is currently being evaluated as a single agent 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. In clinical trials conducted to date, voreloxin has been generally well tolerated and has shown objective responses in both solid and hematologic tumor types.

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 Pharmaceuticals, please visit http://www.sunesis.com.

Contacts
Eric Bjerkholt
650-266-3717