Regeneron's Arcalyst Reduced Painful Gout Flare-Ups by 80%, Research Finds

Regeneron Pharmaceuticals Inc.’s Arcalyst cut by 80 percent the recurrence of painful flare-ups of gout in a study. The drug didn’t work to reduce pain once the condition began, a second trial found.

Patients showed a reduction in the number of flare-ups after 16 weeks of therapy with a once-weekly dose of 160 milligrams of the medicine, the Tarrytown, New York-based company said today in a statement. In the second study, Arcalyst didn’t diminish pain from an ongoing gout flare-up more than an already-approved painkiller from 24 to 72 hours after treatment began.

Gout, a form of arthritis more likely to affect men, occurs when uric acid builds up in the blood. About 3 million Americans have the disorder, according to the Atlanta-based Arthritis Foundation. If Arcalyst is approved for gout flare-ups, it could generate an additional $500 million a year in peak annual sales for the company, Joseph Pantginis, an analyst for Roth Capital Partners in New York, said in an interview before the results were reported.

For patients who took Arcalyst to prevent flares, a once- weekly dose of 80 milligrams had a 73 percent decrease in the number of flares, with an average of 0.29 flares in the treatment group versus 1.06 flares in the placebo group, Regeneron said in the statement.

Arcalyst also lowered the number of patients who had two or more flares by 88 percent, compared with 31.6 percent on placebo. There were no drug-related serious adverse events, according to the company’s statement.

Hereditary Disease

Arcalyst is currently approved to treat cryopyrin- associated periodic syndromes, or CAPS, a hereditary disease. It works by binding to certain proteins, stopping them from activating cell receptors. In the case of gout, this hinders an inflammatory process. The drug doesn’t work against the root cause of the disease, which is the buildup of uric acid in the blood, according to the American College of Rheumatology.

Medications that lower uric acid can cause more flares during treatment, leading some patients to discontinue use, said Ralph Schumacher, a professor of medicine at the University of Pennsylvania, in Regeneron’s statement.

To contact the reporter on this story: Elizabeth Lopatto in New York at

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