Board Recommends Continuation of Sunesis Pharmaceuticals' VALOR Trial

The VALOR trial is a Phase 3, randomized, double-blind, placebo-controlled, pivotal trial of vosaroxin, the Company's lead product candidate, in patients with first relapsed or refractory acute myeloid leukemia (AML).

The adaptive design of the VALOR trial also provides for a single interim analysis by the DSMB, expected in mid-2012, to examine pre-specified efficacy and safety data sets and decide whether to stop the study early for efficacy or futility, continue the study as planned or implement a one-time sample size adjustment of 225 additional evaluable patients. Without a sample size adjustment, the unblinding of the trial is currently expected in 2013.

"The DSMB recommendation to continue as planned reinforces our confidence in the design and conduct of the VALOR trial, one of the largest industry-sponsored trials undertaken in this AML setting," stated Daniel Swisher, Chief Executive Officer of Sunesis. "As of today, 168 patients have been enrolled with more than half being enrolled since early September, thus highlighting the enthusiasm for VALOR among our investigators. We hope that the promising safety/tolerability profile and anti-leukemic activity exhibited by vosaroxin during our Phase 2 program will translate into improved clinical outcomes for relapsed and refractory AML patients."