Drug Decisions Cause Outbreak of Shock
Recommendations by FDA panels that COX-2 drugs remain in use are criticized by doctors, activistsFeb 20, 2005 | Newsday
In the last decade, the public has seen a series of high-profile drugs designed to treat everything from diabetes to heartburn banished from the market, and it was widely believed early last week that the painkillers called COX-2 inhibitors would succumb to the same fate.
But when two Food and Drug Administration panels narrowly voted on Friday to allow Vioxx to make a comeback and for Celebrex and Bextra to remain on pharmacy shelves many doctors and health care activists responded to the decision with shock.
Just days before the vote, a flurry of medical studies demonstrated that each of the medications was inherently dangerous, capable of raising the risk of heart attacks, strokes and a wide range of other cardiovascular problems.
Dr. Jeffrey Drazen, editor of The New England Journal of Medicine, wrote in a blistering editorial that perhaps it was time to end the problematic pharmaceutical run of the drug class called COX-2.
Nevertheless, proponents who pleaded with FDA panelists to keep the drugs spoke of patients who need them to beat back chronic pain.
Dr. Mark Fendrick, a professor of medicine at the University of Michigan, said that despite the controversy, judicious use can help sidestep potential dangers. "Now that the FDA panel has noted the potential for all COX-2 inhibitors to increase the risk of adverse cardiovascular events, their use should be limited to individuals at risk for stomach injury and those who are at low risk for cardiac problems."
COX-2 inhibitors, initially dubbed super-aspirin, prevent the stomach ulceration associated with aspirin.
Too fast to spot dangers
Critics Friday were less diplomatic, charging that the drugs entered the market on fast-track approvals based on small industry-run studies that were not strong enough to spot the dangers that have unfolded. Troubles linked to Merck's Vioxx and Pfizer's two drugs, Celebrex and Bextra, are emblematic of medications that are fast-tracked and over-hyped, experts said Friday.
"These are weapons of mass destruction," said Dr. Sidney Wolfe, director of consumer watchdog Public Citizen's Health Research Group, referring to the drugs. Wolfe, one of the most vocal critics of the pharmaceutical industry and the FDA, said the decision to leave COX-2 inhibitors on the market "defies common sense."
Vioxx was never banned
Two FDA expert panels heard testimony about the medications from proponents and critics during a three-day hearing last week, and while the panels' vote is merely a recommendation to keep the drugs in pharmacies, the FDA, which has final word, generally abides by its advisers' conclusions.
Vioxx, voluntarily withdrawn by Merck in September when heart risks first surfaced in a cancer prevention trial, was never banned by the FDA. Questions remain about how the agency will re-evaluate it in the near future. It may be difficult finding volunteers for a clinical trial.
"How would they test it? It would be unethical to give it to people" in a clinical trial now that the heart dangers are known, said Dr. Bruce Psaty, a professor of medicine and cardiology at the University of Washington in Seattle. "The FDA is currently underpowered to get things done that need to be done in terms of safety."
The re-emergence of a troubled drug would not be unprecedented, added Wolfe, who pointed to Lotronex, a drug linked to five deaths that was banned by the FDA in 2000. The agency reversed itself in 2002 after a re-evaluation and pleas from patients stricken with irritable bowel syndrome, who said Lotronex was their only form of relief.
But Wolfe said a potential return of Vioxx would be nothing like the comeback of Lotronex. Doctors now are required to use a cumbersome algorithm to prescribe Lotronex and to be well-educated in its benefits and risks. "Lotronex came back under an extraordinarily restricted program and there is nothing like that for these drugs. There's nothing to stop doctors from prescribing them," Wolfe said.
Bextra already carries an FDA "black box" warning. A majority of panelists on Friday felt similar stringent warnings were in order for all drugs in the class.
"I think it's totally chaotic," said Dr. Stanley Katz, chief of cardiology at North Shore University Hospital in Manhasset. "I don't think anyone is 100 percent sure of what to do.
"If I have a patient who wants to take them, I really don't know enough about the effects of these drugs to advise the patient."
"These drugs were fast-tracked based on a promise that turned out to be false," Wolfe added. "They were on a fast track because it was believed they protected the gastrointestinal tract, but of course we know that so-called benefit was completely swamped by the massive risk for heart attacks."
Study published last week
On Tuesday, Dr. Rober Bresalier of M.D. Anderson Cancer Center in Houston, reported in The New England Journal of Medicine that patients who took 25 milligrams of Vioxx daily to prevent colorectal polyps were twice as likely to experience heart attacks and strokes as people who took a placebo. The trial was stopped Sept. 30, when the heart risks were first discovered.
A similar analysis of polyp patients at Brigham and Women's Hospital in Boston found that 200 milligrams of Celebrex a day doubled the risk of cardiovascular problems and 400 milligrams tripled the risk.
"I think of these drugs as absolutely the last resort," Psaty said. "They are known to increase cardiovascular disease risk and there is no additional evidence of benefit. There is no evidence that they are superior to aspirin or Tylenol.
"So the medical rational for using these drugs is not clear to me. They're expensive and potentially risky without any clear advantages," Psaty said.
Despite the cardiovascular risks of the three COX-2 inhibitors, hints from cancer-prevention studies suggest that at least Vioxx and Celebrex can prevent the development of polyps. And while details are expected later this year, doctors now say they must weigh the drugs' potential benefits against the seriousness of their risks.