Ardea Biosciences, Inc. (Nasdaq: RDEA) announced positive, preliminary, top-line results from its Phase 2b monotherapy study of RDEA594, its lead product candidate for the treatment of hyperuricemia and gout.
In this 28-day, randomized, double-blind, placebo-controlled, dose-escalation study, 123 gout patients with hyperuricemia (serum urate levels greater than or equal to 8 mg/dL) received 200 mg once-daily (qd) RDEA594, 400 mg qd RDEA594, 600 mg qd RDEA594 or matching placebo. For patients receiving 400 mg qd RDEA594 and 600 mg qd RDEA594, their dose was titrated up weekly in increments of 200 mg/day. This study specifically enrolled patients who excrete less than normal amounts of uric acid at baseline (under-excretors of uric acid make up approximately 90% of all gout patients). All patients received colchicine for prophylaxis against flares. The primary endpoint of the study was a significant increase in the proportion of patients who achieved a response, defined as a reduction of serum urate to < 6 mg/dL after 4 weeks of treatment, compared to placebo.The primary endpoint was achieved in this study. Reductions in serum urate and response rates increased in a dose-related manner and were highly clinically and statistically significant at both the 400 mg qd and 600 mg qd dose levels. At the highest dose, there was a 38% median reduction in serum urate levels after 4 weeks compared to a 1% increase on placebo (p < 0.0001). This translated into a response rate of 45%, compared to 0% for placebo (p < 0.0001).