"This study shows a strong association between treatment with TNF-blocking antibodies and the development of serious infections, such as pneumonia, and cancers," says Eric Matteson, M.D., Mayo Clinic rheumatologist and a senior study investigator. "It's a very serious issue. TNF-blocking antibodies are effective for treatment for rheumatoid arthritis and related conditions, but patients and health care providers must know that there is an increased risk for these complications and be alert for them."

More than half a million patients have received therapy with TNF-blocking antibodies. Patients treated with these drugs usually have not had favorable results with other drug treatments for rheumatoid arthritis or have more severe disease, according to Dr. Matteson. The drugs also are used to treat psoriasis, Crohn's disease and other conditions.

The study involved a systematic literature search for trials of TNF-blocking antibodies for rheumatoid arthritis. In addition, the researchers searched for such trials in the abstract databases of the scientific meetings of the American College of Rheumatology and the European League Against Rheumatism through December 2005 and conducted interviews with the manufacturers of the two licensed TNF-blocking antibodies, infliximab and adalimumab. The investigators found nine trials that met their inclusion criteria, including 3,493 patients who received TNF-blocking antibodies and 1,512 patients who received placebo. They gathered all data related to serious infections and malignancies in the studies' participants. Collectively, using various types of analyses, the researchers found that those treated wi
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Contact: Lisa Lucier
newsbureau@mayo.edu
507-284-5005
Mayo Clinic
16-May-2006