Arthritis Drugs to Carry Fungus Warning

(September 7, 2008) - Four drugs, commonly used to treat rheumatoid arthritis (Read about "Rheumatoid Arthritis"), will now have to carry a warning about fungus infections. (Read about "Microorganisms") The manufacturers of Humira, Cimzia, Enbrel, and Remicade must strengthen the existing warnings, in the Warnings and Precaution sections of the drugs' prescribing information and Medication Guides, on the risk of developing opportunistic fungal infections. Some patients with invasive fungal infections have died.

The four drugs, known as tumor necrosis factor alpha blockers (TNF-alpha blockers), which suppress the immune system (Read about "The Immune System"), are approved to treat a variety of conditions which may include rheumatoid arthritis, juvenile idiopathic arthritis, psoriatic arthritis, plaque psoriasis, ankylosing spondylitis, and Crohn's disease. (Read about "Arthritis & Rheumatic Diseases" "Crohn's Disease")

Since the initial approval of the four TNF blockers, the prescribing information for these drugs has included information about the risk of serious infections, including fungal infections. However, based on reports reviewed by the Food and Drug Administration (FDA), health care professionals are not consistently recognizing cases of histoplasmosis and other invasive fungal infections, leading to delays in treatment.

Patients taking TNF blockers should be aware that they are more susceptible to serious fungal infections. Those who develop a persistent fever, cough, shortness of breath, and fatigue should promptly seek medical attention. To assist in the diagnosis, those being treated with TNF blockers should tell their health care professionals where they live and what areas they have recently visited. Patients who develop a fungal infection may be advised to stop the TNF blocker until they recover.

FDA has reviewed 240 reports of histoplasmosis, an infection caused by the fungus Histoplasma capsulatum, in patients being treated with Enbrel, Humira, or Remicade. The majority of the reports involved people in the Ohio River and Mississippi River valleys (the fungus is commonly found in those areas). In at least 21 of the reports, histoplasmosis was initially not recognized by health care professionals, and antifungal treatment was delayed. Twelve of those patients died.