Jan. 24, 2005 -- A pharmaceutical watchdog group called on federal regulators Monday to ban two prescription pain relief medications similar to Vioxx, saying the drugs increase the risk of heart attacks and other cardiovascular problems.
Public Citizen filed a petition with the FDA asking the agency to immediately remove Celebrex and Bextra from the market. Celebrex and Bextra are two arthritis drugs in a class known as Cox-2 inhibitors. According to the group, Americans filled more than 36 million prescriptions of these drugs last year.
Public Citizen is a longtime critic of both the pharmaceutical industry and the FDA, and it independently warned patients more than four years ago that Celebrex was unsafe.
The group said Monday that studies show that Celebrex and Bextra increase the likelihood of dangerous heart problems while offering patients little or no benefit over older pain relievers.
"Both drugs are fundamentally dangerous, and the only way of dealing with that is to get them off the market," Sidney Wolfe, MD, head of Public Citizen's Health Research Group, tells WebMD.
Wolfe says the group does not have data suggesting how many adverse health events may have resulted from the use of the two drugs.
Similar Drug Pulled From Market
The petition comes after Merck & Co. voluntarily pulled Vioxx from the market in September 2004 following reports of increased heart attack risk in patients taking it. The move prompted some experts to speculate that the side effects are not unique to Vioxx but could be shared by the entire class of Cox-2 inhibitor drugs.
FDA scientist David Graham, MD, singled out Bextra and four other prescription drugs as potentially unsafe in November 2004 when he testified in front of the Senate Finance Committee about drug safety problems at the FDA.
In one study published in 2000, researchers found that patients taking Celebrex had a slightly higher chance of developing chest pain (angina) than those taking ibuprofen. The study findings did not reach mathematical significance, meaning the results could have been by chance. However, FDA scientists at the time cited a "consistent and worrisome trend" in several studies pointing to cardiovascular toxicity caused by the drug.
At the same time, the study, known as CLASS, found no difference in the rate of serious stomach or intestinal complications in patients who took Celebrex or ibuprofen, according to Public Citizen's complaint.
Then, in December 2004, the National Institutes of Health abruptly halted a colon polyp study after preliminary data suggested that patients taking Celebrex were up to 3.4 times more likely than those taking a placebo to have a heart attack, stroke, or a sudden, heart-related death.
Pfizer said at that time that it was taking steps to address the new data revealed in the NIH study, and it also pointed to another large-scale NIH trial showing no increased cardiovascular risk due to Celebrex. The company issued a statement several days later urging doctors to use "the lowest effective dose" of Celebrex in patients with joint pain due to arthritis or other causes.
Pfizer did not respond to requests for comment on Monday's petition to the FDA.
An FDA spokesperson says the agency plans to review the petition "very carefully." The agency is planning to convene an expert advisory committee next month to conduct a broad review of Cox-2 inhibitor drugs.
More Questions About Bextra
An analysis slated for publication next week in the medical journal Circulation also questions the safety of Bextra by concluding that the drug caused a more than threefold increased risk of cardiovascular side effects in patients who had undergone heart bypass surgery.
Curt D. Furberg, MD, the study's lead researcher, tells WebMD that while the analysis was limited to patients already at high risk of heart attack, as many as half of all arthritis patients also meet criteria for heart disease risk. Bextra's safety has not been adequately studied in the general population since the studies used to gain FDA approval generally excluded those deemed at risk for cardiovascular problems, he says.
"This is the best we've got. Generalizable studies haven't been done," says Furberg, a professor of pubic health sciences at the Wake Forest University School of Medicine.
Furberg declined to comment directly on calls to ban Celebrex and Bextra. But he says data are mounting to suggest that the benefits of Cox-2 inhibitor drugs may not be worth their risks.
"My general view is that the cloud over all the Cox-2 drugs is getting darker and darker," he says.
The FDA in December issued a public warning of the risks of Cox-2 inhibitor use and announced it was strengthening Bextra's product label to alert doctors and patients of cardiovascular risks.