San Diego’s Ardea Biosciences (NASDAQ: RDEA) appears to have stubbed a toe in its development of RDEA 594 as a first-line treatment for gout. Data presented at a medical meeting in Philadelphia today showed the Ardea drug was no better at controlling gout than existing medications, including allopurinol, a cheap generic. During a conference call with investors today, CEO Barry Quart says Ardea’s chief focus is on developing RDEA 594 as an add-on or alternative for patients who do not respond adequately to existing drugs. Quart says the potential market for RDEA 594 remains quite large since 60 percent of gout patients do not fully improve on the mainstay drug allopurinol.
Ardea is testing its drug in combination with allopurinol and in combination with febuxostat, a newer drug marketed by Takeda under the name Uloric, Quart said. A mid-stage trial pitting RDEA 594/allopurinol against allopurinol alone in gout patients is now underway, with data expected by the end of the year. Development of the febuxostat/RDEA 594 combination is not as far along; an early-stage study is being conducted in 54 healthy volunteers to look at the safety of the drug combination. If results are good, Ardea will test the drug combination in people with gout. Quart said animal studies to date have supported the safety of the drug combinations.
Adrea still believes RDEA 594 may be useful as a standalone treatment for people who can’t tolerate or don’t benefit from allopurinol. However, developing RDEA 594 as a monotherapy is not a major focus, according to the company. “We have to be realistic,” said Ardea spokesman John Beck, noting the company has been shifting the focus of its development program for “the last couple quarters.”
Quart’s comments came as Ardea presented fresh data from clinical studies of RDEA 594 at the annual meeting of the American College of Rheumatology/ Association of Rheumatology Health Professionals. Data from a small trial of 21 gout patients shows that RDEA 594 can reduce the amount of uric acid in patients’ blood without serious side effects. But the study also shows RDEA 594 is no more effective than allopurinol. According to the poster presentation, “response rates seen with RDEA 594 were consistent with that seen with currently marketed products…”
Gout is a form of arthritis caused by the buildup of uric acid crystals in the joints. The condition can cause redness, swelling and pain; the first sign of gout is typically a swollen, painful big toe. Gout affects 2.1 million Americans, most of them men, according to the National Institutes of Health. However, estimates vary, and Ardea told investors today that the number of potential patients in the U.S. could exceed 5 million. The majority of gout sufferers are men. RDEA 594 steps up the amount of uric acid excreted in urine; about 90 percent of people with gout excrete too little uric acid. RDEA 594 works differently from allopurinol, which reduces the buildup of uric acid in the blood stream. This difference in the mechanism of action is one reason why Ardea believes combination drug treatments make sense.
Ardea started work on RDEA 594 after observing an experimental HIV drug reduced levels of uric acid in the blood. Sensing potential opportunity in gout, a disease with few approved treatments, the company did some further research and learned that a metabolite of the HIV drug—a molecule shed when the HIV drug broke down in the body—was responsible. RDEA 594 is a form of that metabolite.
Also on the call, Quart gave investors an update on Ardea’s cash position. He said the company expects to have $50 million to $55 million in cash at the end of 2009, providing it with enough funds to continue operations through the first quarter of 2011.