Preclinical Data on Lead MEK Inhibitor, RDEA119, to be Presented at the 2007 AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Th...(matory diseases such asrheumatoid arthri...),Health

RDEA119, Ardea's lead compound from this program, is a potent, non-ATP competitive, highly selective inhibitor of MEK. Ardea plans to initiate a Phase 1 clinical trial evaluating RDEA119 in advanced cancer patients in the second half of 2007. Preclinical data suggest that RDEA119 may have favorable pharmaceutical properties, including the potential for convenient oral dosing and limited retention in the brain, which, in turn, may result in a reduced risk of CNS side effects. Beyond RDEA119, the Company is evaluating a broad range of MEK inhibitors from several distinct chemical classes and plans to bring forward one of these compounds into a first-in-human study in the fourth quarter of this year.

About Ardea Biosciences, Inc.

Ardea Biosciences is focused on the discovery and development of small-molecule therapeutics for the treatment of viral diseases, cancer and inflammatory diseases. The Company plans to initiate clinical studies on four compounds this year. These include RDEA806, the Company's lead non-nucleoside reverse transcriptase inhibitor (NNRTI) for the treatment of HIV, which recently completed Phase 1 clinical trials, RDEA119, a mitogen-activated ERK kinase (MEK) inhibitor for the treatment of cancer and inflammatory diseases, which has been cleared by the FDA to enter Phase 1 clinical trials, and a follow-on NNRTI and a follow-on MEK inhibitor, both of which are scheduled to enter first-in-human studies in the fourth quarter of 2007.

Statements contained in this press release regarding matters that are not historical facts are "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. Because such statements are subject to risks and uncertainties, actual results may differ materially from those expressed or implied by such forw
'/>"/>