WASHINGTON - Blockbuster prescription drugs used to treat rheumatoid arthritis and other autoimmune conditions can increase the risk of potentially deadly cancer in children and teenagers, the Food and Drug Administration said yesterday, ordering stronger warnings on such medications.
The FDA, which urged greater caution with so-called TNF blockers last September, said an analysis of 48 reported cancer cases in children using the drugs "showed an increased risk of cancer, occurring after 30 months of treatment on average." Eleven of the reported cases were fatal, the agency said.
After more than a year of review, FDA scientists said the group of best-selling drugs used to treat arthritis and other inflammatory diseases, appear to increase the risk of lymphoma after they are used beyond 2 1/2 years.
The drugs are known as tumor necrosis factor (TNF) blockers and work by neutralizing a protein that, when overproduced, causes inflammation and damage to bones, cartilage and other tissue.
In children, the drugs are mainly prescribed to treat rheumatoid arthritis, inflammatory bowel disorder and Crohn's disease. More broadly, they are approved to treat a variety of chronic, inflammatory and autoimmune system diseases including juvenile idiopathic arthritis, rheumatoid arthritis, psoriatic arthritis, plaque psoriasis and ankylosing spondylitis.
The agency will bolster the "black box" warning on the five drugs sold in the U.S., including Abbott Laboratories' Humira, Johnson & Johnson's Remicade and Simponi, and Enbrel, which is co-marketed by Amgen Inc. and Wyeth.
The action also affects Belgian drugmaker UCB's Cimizia.
Shares of North Chicago-based Abbott Laboratories and New Brunswick, N.J.-based Johnson & Johnson fell after the FDA announcement.
Along with updating the drugs' labels, the FDA is requiring companies to add information about cancer risks to patient medication guides. The FDA said it is also working with the manufacturers to further define the scope of the cancer risk.
Johnson & Johnson said in a statement it "will coordinate closely with the FDA to ensure that health care providers, patients and caregivers are properly informed." Amgen and Wyeth said they will continue working with regulators to evaluate "the potential risks and benefits" of their drug.