The Food and Drug Administration announced today that it would require stronger warnings for all TNF blockers, a class of drug used to treat rheumatoid arthritis, Crohn’s disease, and other inflammatory diseases.  The label change includes a black box warning highlighting an increased risk of cancer in children and adolescents using adalimumab (Humira), certolizumab pegol (Cimzia), etancercept (Enbrel), golimumab (Simponi), and infliximab (Remicade).

In 2008 the FDA announced an investigation into the drugs had found that they can interfere with a protein called tumor necrosis factor, increasing the risk of life-threatening infections and certain cancers. Based on that information, the agency issued a black box warning about infections from etanercept (Enbrel), including serious infections leading to hospitalization or death. Doctor’s were advised to screen patients for latent tuberculosis infection before starting on Enbrel, and recommended that patients educate themselves about the symptoms of infection and closely monitor any signs and symptoms of infection during or after treatment with the drug.

The FDA says that today’s announcement marks the completion of the investigation, which looked at surveillance reporting data and found that children treated with TNF blockers showed an increased risk of cancer. About half of the cancers reported were lymphomas, which involve cells of the immune system, and occurred, on average, after 30 months of treatment. Some were fatal. The agency says it is continuing to work with manufacturers of the drugs to further understand the cancer risk.