COX-2 Hearing

DRUG SAFETY

An FDA advisory panel has recommended that three leading arthritis drugs--Celebrex, Bextra, and Vioxx--be allowed to remain on the market. Now, the agency must decide whether it will heed that advice, given studies that show an increased risk of cardiovascular problems in people who take the drugs.

The FDA Arthritis Drug Advisory Committee on Feb. 18 concluded unanimously that all three cyclooxygenase-2 (COX-2) inhibitors increase the risk of heart attack and stroke in patients using the drugs. What's more, they recommended that the strongest possible warnings--so-called black-box warnings--be placed on the drugs' bottle or box to notify patients of the potential dangers.

But the votes on whether these products should be banned were not unanimous. The panel voted 31 to 1 against banning Celebrex, 17 to 13 against banning Bextra, and 17 to 15 against banning Vioxx. Merck withdrew Vioxx from the market on Sept. 30, 2004, after discovering that it doubles the risk of cardiovascular problems.

The panel also advised that no direct-to-consumer advertising should be allowed for COX-2 inhibitors and that drug information included with the prescription should also carry written warnings about the cardiovascular risks.

Alastair J. J. Wood, chairman of the FDA panel and professor of pharmacology at Vanderbilt University Medical Center, says: "It was clear to the committee that all three COX-2 drugs increased the risk of heart attack in patients. Although it is currently unclear which, if any, group of patients can safely take these drugs, it would be unwise to give them to patients with risk factors for heart disease."

FDA is not required to follow the advice of its expert panels, but it generally does. The agency is expected to decide in a few weeks whether Pfizer's Bextra and Celebrex should remain on the market and whether to allow Merck, if the company chooses, to once again sell Vioxx.

If these were the only painkillers that cause cardiovascular problems, FDA's decision would be easy. According to the panel, older drugs like ibuprofen and diclofenac may also have adverse effects on the heart, but their risks are not as well researched. And the newer nonsteroidal anti-inflammatory drug (NSAID) Aleve may also increase cardiovascular risk when used over long periods.

Larry D. Sasich, a pharmacist with Public Citizen's Health Research Group, says it appears that neither of the two COX-2 inhibitors still available is safer for the gastrointestinal tract than the older NSAIDs. Gastrointestinal side effects of NSAIDs pushed the development of COX-2 inhibitors. "I can see no reason to keep COX-2 inhibitors on the market. The NSAID ibuprofen appears the safest," he says.

It is not clear that Vioxx poses unique risks among COX-2 inhibitors, Peter S. Kim, president of Merck Research Laboratories, told the panel. Vioxx was the only COX-2 drug that caused fewer gastrointestinal events than Aleve, and "we have heard numerous reports from patients" that Vioxx is the only medicine that relieves their pain, he said.