Ardea Biosciences, Inc. (Nasdaq: RDEA) announced preclinical data on its lead non-nucleoside reverse transcriptase inhibitor (NNRTI) candidate, RDEA806, demonstrating no reproductive toxicity. In addition, novel second-generation NNRTI, RDEA427, was selected as a development candidate for the potential treatment of the human-immunodeficiency virus (HIV), the causative agent of AIDS.

Animal reproductive toxicity studies recently completed with RDEA806 have demonstrated no effects on male or female fertility or on early embryonic development at all tested doses. These results are in contrast to the fetal malformations reported in other NNRTI animal reproductive toxicity studies.

Exploratory human testing (Phase 0) of RDEA427 was recently completed in which micro-doses of the compound were administered to healthy volunteers. Preliminary pharmacokinetic data from this study, produced by Vitalea Science, Inc. using Accelerator Mass Spectrometry (AMS) technology, demonstrated that RDEA427 has a half-life of approximately 40 hours, which could permit once daily oral dosing.

"The ability to use RDEA806 in women, without the risk of birth defects, is a major advantage over the current first-line NNRTI. Women make up 26% of HIV/AIDS diagnosed patients in the United States, and an even larger percent of infected patients worldwide. These preclinical data for RDEA806 further strengthen its impressive product profile," said Barry D. Quart, PharmD, Ardea Biosciences' President and CEO. "In addition, the excellent preclinical properties of RDEA427 and its long half-life in humans make it the perfect candidate to progress into clinical testing. Developing both RDEA806 and RDEA427 in tandem is consistent with our business strategy of keeping Ardea's pipeline full of novel compounds in areas that are underserved by current treatment options. We are on track to begin a Phase 1 trial with RDEA427 later this year, and expect to initiate a Phase 2b trial with RDEA806 in the third quarter of this year."

About RDEA806 and RDEA427

RDEA806 and RDEA427 are novel, structurally different NNRTIs for the potential treatment of HIV infection. Based on preclinical and clinical studies to-date, Ardea believes that RDEA806 and RDEA427 may have important competitive advantages. These include: the potential for potent antiviral activity against a wide range of HIV viral isolates, including those that are resistant to efavirenz (Sustiva(R), Bristol-Myers Squibb); a high genetic barrier to resistance; the potential to be administered in a patient-friendly, oral dosing regimen; limited pharmacokinetic interactions with other drugs; and the ability to be co-formulated with other HIV antiviral drugs. RDEA806 reproductive toxicity data indicates that future studies, including Ardea's planned Phase 2b trial, would likely include women of child-bearing age in anti-retroviral naive HIV-infected patients.

About Ardea Biosciences

Ardea Biosciences, Inc., of San Diego, California, is a biotechnology company focused on the discovery and development of small-molecule therapeutics for the treatment of HIV, cancer and inflammatory diseases, including gout. We have four drug candidates in clinical trials and others in preclinical development and discovery. Our most advanced development candidate is RDEA806, a non-nucleoside reverse transcriptase inhibitor (NNRTI), which is in a Phase 2a study for the treatment of HIV. We have evaluated our second-generation NNRTI for the treatment of HIV, RDEA427, in a human micro-dose pharmacokinetic study and have selected it as a development candidate. RDEA594, our lead development candidate for the treatment of gout, is in preclinical development and is believed to be an inhibitor of the URAT1 transporter in the kidney, which is responsible for regulation of uric acid levels. We are evaluating our lead MEK inhibitor, RDEA119, in a Phase 1 study in advanced cancer patients, as well as in a Phase 1 study in normal healthy volunteers as a precursor to trials in patients with inflammatory diseases. Lastly, we have evaluated our second-generation MEK inhibitor for the treatment of cancer and inflammatory diseases, RDEA436, in a human micro-dose pharmacokinetic study and have selected it as a development candidate.

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 forward-looking statements. Such statements include, but are not limited to, statements regarding our goals, including the expected properties and benefits of RDEA806, RDEA427, RDEA594, RDEA119, RDEA436 and our other compounds and the results of preclinical, clinical and other studies. Risks that contribute to the uncertain nature of the forward-looking statements include: risks related to the outcome of preclinical and clinical studies, risks related to regulatory approvals, delays in commencement of preclinical and clinical studies, and costs associated with our drug discovery and development programs and business development activities. These and other risks and uncertainties are described more fully in our most recently filed SEC documents, including our Annual Report on Form 10-K and our Quarterly Reports on Form 10-Q, under the headings "Risk Factors." All forward-looking statements contained in this press release speak only as of the date on which they were made. We undertake no obligation to update such statements to reflect events that occur or circumstances that exist after the date on which they were made.

Ardea Biosciences, Inc.
http://www.ardeabio.com