(HealthDay)—Xeljanz (tofacitinib) has been approved by the U.S. Food and Drug Administration to treat symptoms of rheumatoid arthritis (RA) among people who can't tolerate, or haven't been helped by, the drug methotrexate.
RA is an autoimmune disease in which the immune system mistakenly attacks the body. In the case of RA, this leads to swelling of the joints and nearby tissues. About 1.5 million Americans have RA, the FDA said in a news release.
A twice-daily pill, Xeljanz is designed to block molecules involved in joint inflammation, the FDA said.
The drug was evaluated in seven clinical studies of adults with moderate-to-severe RA. The drug carries a "black box" label warning of an increased risk of infection triggered by a suppressed immune system, and tuberculosis and certain cancers.
Other serious side effects could include increased cholesterol levels and liver enzyme problems, the FDA said. More common adverse reactions were upper respiratory tract infections, headaches, diarrhea and nasal inflammation.
Xeljanz is marketed by New York-based Pfizer Inc.
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The U.S. National Library of Medicine has more about rheumatoid arthritis.