RDEA806 Moves into Phase 2b

SAN DIEGO, Oct 27, 2008 (BUSINESS WIRE) -- Ardea Biosciences, Inc. (Nasdaq:RDEA) announced today that additional data from a Phase 2a monotherapy study of RDEA806, our lead non-nucleoside reverse transcriptase inhibitor (NNRTI) in development for the treatment of human immunodeficiency virus (HIV), were presented at the 48th Annual ICAAC/IDSA 46th Annual Meeting in Washington, DC.

Dr. Graeme Moyle, Director of HIV Research, Chelsea and Westminster Hospital, gave an oral presentation showing that in the Phase 2a study, RDEA806 demonstrated robust antiviral activity with a well-tolerated profile and confirmed a low potential for drug interactions. Data from the study also showed that 800mg of RDEA806 administered once daily produced similar viral load reductions as 400mg of RDEA806 administered twice daily, supporting initiation of a Phase 2b study using once daily doses of RDEA806. In addition, Dr. Moyle presented preliminary data from a Phase 1 drug-drug interaction study of RDEA806 and Truvada(R) (Gilead Sciences) showing no interaction with either of its components (emtricitabine or tenofovir disoproxil fumarate). Ardea recently received regulatory approval from the Medicines and Healthcare products Regulatory Agency (MHRA) in the United Kingdom to conduct a Phase 2b study comparing RDEA806 to efavirenz (SUSTIVA(R)/Stocrin(R), Bristol-Myers Squibb/Merck) in anti-retroviral treatment of naAve patients without transmitted resistance, receiving background treatment with Truvada.

In addition, Dr. Anneke Raney, director, virology, presented preclinical virology data (poster H-1222) showing RDEA806 has a high genetic barrier to resistance and limited cross-resistance to other NNRTIs. Consistent with these in vitro data, no genotypic or phenotypic changes were observed during the Phase 2a study following one week of monotherapy with RDEA806.

"We look forward to initiating the Phase 2b study of RDEA806, an important step forward in the development of this product candidate for the treatment of HIV-infected patients," commented Barry D. Quart, PharmD, Ardea's president and chief executive officer.

The presentation and poster are available on the Company website (http://www.ardeabio.com) under the titles, "RDEA806, a Novel Non-Nucleoside Reverse Transcriptase Inhibitor, Shows Positive Outcome in Treatment of NaAve HIV Patients," and "Resistance to RDEA806 Requires Multiple Mutations Which Have Limited Cross-Resistance to Other NNRTI's," respectively.

About RDEA806

RDEA806 is a novel NNRTI for the potential treatment of HIV infection. Based on preclinical and clinical studies to-date, we believe that RDEA806 may have important competitive advantages compared to currently available NNRTIs. These include the potential for potent antiviral activity against a wide range of HIV viral isolates, including those that are resistant to efavirenz and other currently available NNRTIs; a high genetic barrier to resistance; no reproductive toxicity based on animal studies; 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.

About Ardea Biosciences, Inc.

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, gout, cancer and inflammatory diseases. We have five product candidates in clinical trials and others in preclinical development and discovery. Our most advanced product candidate is RDEA806, an NNRTI, which has successfully completed a Phase 2a study for the treatment of patients with HIV and is entering Phase 2b. We have evaluated our second-generation NNRTI for the treatment of HIV, RDEA427, in a human micro-dose pharmacokinetic study and have selected it for clinical development. RDEA594, our lead product candidate for the treatment of hyperuricemia and gout, is being evaluated in a Phase 1 clinical trial 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 1/2 study in combination with sorafenib (Nexavar(R), Onyx Pharmaceuticals, Bayer HealthCare) and as a single agent in a Phase 1 study, both in advanced cancer patients, and have completed 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 for clinical development.

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 plans and goals, the expected properties and benefits of RDEA806, RDEA427, RDEA594, RDEA119, RDEA436 and our other compounds, and the timing and results of our 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, costs associated with our drug discovery and development programs, and risks related to the outcome of our 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.

SOURCE: Ardea Biosciences, Inc.

Ardea Biosciences, Inc. 
John Beck, 858-652-6523 

jbeck@ardeabio.com

Copyright Business Wire 2008

News Provided by COMTEX