Like its predecessor, Vioxx -- and its primary competition, Celebrex -- Arcoxia is a COX-2 inhibitor, a drug meant to have the same benefits of non-steroidal anti-inflammatory drugs without the risks of bleeding stomach ulcers and other serious digestive tract problems associated with that class of drugs.
Vioxx was taken off the market in September 2004 after it was linked to a severe increase in risk of cardiovascular problems and was thought to have caused between 88,000 and 139,000 heart attacks, about 30 to 40 percent of which were fatal.
In his editorial, printed in the online edition of the Journal of the American Medical Association, Graham said that, in the consideration of Arcoxia's approval, "the FDA, academia, and the medical research enterprise are once again faced with the opportunity to forsake common sense by willfully accepting misdirection and disinformation presented in the guise of science."
An editor's note clarified that the editorial was accepted from Graham as a public citizen rather than an employee of the FDA, and a JAMA press release stated the article was printed online "because of the public health implications."
Some of the concern about Arcoxia comes from the fact that Merck scientists stated that the rate of cardiovascular events for Arcoxia were similar to those for diclofenac -- an older arthritis drug -- but a past JAMA article said diclofenac itself could pose as much cardiovascular risk as low-dose Vioxx.
Dr. David Henry, co-author of the diclofenac study and clinical pharmacologist at the University of Newcastle in Australia, said he decided to give his patients naproxen rather than diclofenac.
"(Naproxen) causes gastrointestinal bleeding, no question," he said. "But I'd rather have a gastrointestinal bleed than a heart attack."
Wake Forest University medical epidemiologist Curt Furberg agreed.
"The take-home message is stay away from diclofenac, which is basically another way of saying that Arcoxia is harmful," said Furberg, who sits on the FDA's Drug Safety and Risk Management Advisory Committee.
The Arcoxia/diclofenac comparison results "are consistent with FDA's April 2005 memo stating that long-term clinical trials have not shown a difference in cardiovascular safety (between COX-2s and other NSAIDs), with naproxen as a possible exception," said a statement released by Merck.
JAMA's web site also published a study of 114 clinical trials in which volunteers took a COX-2 inhibitor, another NSAID, or a placebo. Of the drugs, only Vioxx was found to increase the risk of heart arrhythmias and kidney-related problems. Co-author Eric Ding, a doctoral candidate at the Harvard School of Public Health, notes that this does not mean the other drugs, including Arcoxia and Celebrex, are safe.
"I just want to say that in the (COX-2) class analysis, Vioxx seemed to stand out," he said.
So far, Merck has received an "approvable letter" from the FDA concerning Arcoxia, asking for data on the drug's safety and efficacy, but the administration has not yet made a decision on the drug, despite the fact it is already sold in 62 countries.
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