LONDON, May 25, 2011 /PRNewswire/ -- Ardea Biosciences, Inc. (Nasdaq: RDEA) announced today that additional positive clinical and preclinical results from its development program of lesinurad, the Company's lead product candidate for the treatment of hyperuricemia and gout, were presented at the Annual European Congress of Rheumatology hosted by the European League Against Rheumatism (EULAR) in London, UK. Results from Primary Dosing Period and Ongoing Extension of Phase 2b Combination Study with Allopurinol Results presented from the ongoing blinded extension portion of Ardea's Phase 2b study (study 203) of lesinurad in patients who did not achieve target on allopurinol therapy alone demonstrated that for those patients who have reached week 28 of the extension period, 91 percent of those patients receiving lesinurad in combination with allopurinol achieved serum urate (sUA) levels below the clinically important target of 6 mg/dL. Importantly, continued reductions in sUA were observed beyond the initial 28 days of dosing with a majority of the responding patients remaining on a 200 mg dose of lesinurad thus far in the extension period. These preliminary results are from the extension portion of a 28-day, randomized, double-blind, placebo-controlled Phase 2b study evaluating lesinurad in combination with allopurinol in 208 gout patients with elevated sUA greater than or equal to 6 mg/dL who were not adequately responding despite being on a stable dose of allopurinol. Following the 28-day primary dosing period and at least a two-week washout, 126 patients entered the optional extension period and restarted dosing with 200 mg of lesinurad or placebo. Non-responding patients can be escalated up to 400 mg or 600 mg of lesinurad, at the investigators' discretion. Currently, 30 patients have been dosed for at least 6 months. Final results were also presented from the completed 28-day main portion of study 203. At the highest lesinurad dose tested in this study, patients achieved a 30 percent mean reduction in sUA levels after 4 weeks, compared to a 3 percent mean increase on allopurinol plus placebo (p< 0.0001). This resulted in a response rate of 79 percent for the 600 mg dose (p< 0.0001) using the more rigorous "intent-to-treat" (ITT) analysis and 87 percent using a "last observation carried forward" (LOCF) analysis. As a result, the number of patients taking the combination who achieved the medically recommended target of below 6 mg/dL was more than three times the number of patients who achieved the target on allopurinol alone.