06/04/08 - FDA to Study if Link Exists Between Childhood Cancer and Abbott's Humira

The U.S. Food and Drug Administration is taking a look at serious health risks in certain patients taking drugs in the same class as two of Abbott Laboratories' top-selling prescription medications.

On Wednesday, the FDA said it will conduct a safety review of Abbott's blockbuster rheumatoid arthritis drug Humira and similar drugs in the same class such as Enbrel and Remicade following a small number of reports such medicines have been linked to cancer risks in children and young adults.

Meanwhile, Abbott's epilepsy drug Depakote and other drugs in its class could face new warnings in their labels about possible risks of suicidal thinking. The FDA said Wednesday it was evaluating the best way to communicate potential risks.

The Abbott Park-based company said it has not heard reports of cancer risk in Humira or of suicidal thoughts in patients who have taken Depakote but was committed to working with the FDA in its evaluations of its drugs.

"There have been no incidents of lymphoma," reported in Humira patients, Abbott spokeswoman Laureen Cassidy said.

Humira, Abbott's top-selling drug, generated $3 billion in worldwide sales last year. Depakote, the company's No. 2 product last year, generated $1.6 billion in sales. Combined, the two products accounted for about 18 percent of total company worldwide sales last year.

The FDA said it is investigating about 30 reports of cancer from the past 10 years in children and young adults taking the so-called TNF blockers.

"The drugs Enbrel, Humira, and Remicade are being reviewed for a possible association between their use and the development of lymphoma and other cancers in children and young adults treated with TNF blockers for juvenile idiopathic arthritis, and Crohn's disease," the FDA said. "Lymphoma is a cancer of the cells in the immune system."

Such drugs are predominantly used to treat rheumatoid arthritis, the most debilitating form of the disease. The bulk of sales of such drugs for Abbott and other makers come from treatments for adults, according to industry reports. It's unclear what, if any impact, the FDA's safety review would have on sales.

Abbott shares rose 27 cents to $56.

The class of drugs works by suppressing the immune system by blocking "the activity of TNF, a substance in the body that can cause inflammation and lead to immune system-related diseases such as juvenile idiopathic arthritis and Crohn's disease," the FDA said.

"This early communication is in keeping with FDA's commitment to inform the public about its ongoing safety reviews of drugs," the FDA said. "Once FDA's review of the new information is complete, FDA will communicate its findings and any resulting recommendations to the public. Health care professionals and caregivers should be aware of the possible association of lymphoma and other cancers in children and young adults when deciding how to best treat this population."

Meanwhile, the FDA would not comment further about any labeling changes for Depakote or other epilepsy drugs, which also include Pfizer Inc.'s Lyrica and Johnson & Johnson's Topamax.

"The FDA has been carefully reviewing data on drugs used to treat epilepsy and is working on finding the most appropriate ways to convey to the public the risks of suicidality that were seen in trials," agency spokeswoman Sandy Walsh said. The FDA is "trying to figure out specific next steps, which may include drug labeling changes and the convening of an advisory committee meeting."

"Abbott's review of its clinical trial data showed no incremental risks of suicidal events with Depakote," Cassidy said. "Given the importance of this information for physicians, Abbott will work to implement any class recommendations recommended by the agency."