Ardea Biosciences completes phase 1 trials of HIV drug RDEA806

Ardea Biosciences, Inc. has announced that it has successfully completed Phase 1 single-ascending-dose, multiple-ascending-dose, food-effect, and drug-interaction studies of RDEA806, a novel HIV non-nucleoside reverse transcriptase inhibitor (NNRTI), in healthy volunteers.

The data from these Phase 1 clinical trials, together with select preclinical data, will be discussed in four poster presentations at the 47th Annual Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC), which is being held September 17-20 in Chicago, Illinois. Abstracts can be accessed on the official ICAAC web site at http://www.icaac.org/ . The poster titles and presentation details are as follows:

• "The Discovery of RDEA806: A Potent New HIV NNRTI in Phase 1 Clinical Trials" will be presented during Poster Session 101 (HIV: New Drugs), Poster Board #299, Abstract #3285, on Tuesday, September 18, 12:15-1:15 PM in Hall D.
• "RDEA806: A Potent NNRTI with Broad Activity Against Resistant Strains of HIV-1 and a High Genetic Barrier to Resistance" will be presented during Poster Session 101 (HIV: New Drugs), Poster Board #300, Abstract #1662, on Tuesday, September 18, 12:15-1:15 PM in Hall D.
• "Safety and Pharmacokinetics of Ascending Single Oral Doses of RDEA806, a Novel HIV NNRTI, in Healthy Volunteers" will be presented during Poster Session 160 (Antiviral Agents), Poster Board #23, Abstract #1609, on Wednesday, September 19, 11:15 AM-12:15 PM in Hall D.
• "RDEA806, a Potent Non-Nucleoside Reverse Transcriptase Inhibitor with Less Potential for Drug-Drug Interactions" will be presented during Poster Session 160 (Antiviral Agents), Poster Board #25, Abstract #3390, on Wednesday, September 19, 11:15 AM-12:15 PM in Hall D.

"We are very encouraged by our Phase 1 clinical trial results in healthy volunteers. Based on these results, we plan to initiate a Phase 2a proof-of-concept study of RDEA806 in HIV-infected patients before the end of this year, the results of which may be available by the first quarter of 2008. Assuming positive results, a larger Phase 2b study in HIV-infected patients could start in the second quarter of 2008," said Barry D. Quart, PharmD, President and CEO. "ICAAC is an international conference where many new therapeutic innovations and discoveries are first disclosed, and we look forward to presenting our preclinical and initial clinical data on RDEA806 at this important meeting."

RDEA806 is a novel non-nucleoside reverse transcriptase inhibitor (NNRTI) for the potential treatment of HIV infection. Based on preclinical and clinical studies to-date, Ardea believes that RDEA806 possesses several attractive attributes. These include: potent antiviral activity against a wide range of HIV viral isolates, including those that are resistant to efavirenz (Sustiva(R), Bristol-Myers Squibb) and other currently available NNRTIs; 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.