The Arcoxia study -- presented at yesterday's meeting of the American Heart Association (AHA) in Chicago -- involved 34,701 patients who took either Arcoxia or diclofenac, a decades-old non-steroidal anti-inflammatory drug.
The study found that the patients taking Arcoxia experienced the same rate of heart complications as those taking diclofenac, but more patients stopped taking Arcoxia because they experienced high blood pressure.
Merck -- which is facing more than 23,000 lawsuits over Vioxx after it was pulled from the market in 2004 for increasing the risk of heart attack and stroke -- was instructed to provide more safety information on Arcoxia after the FDA initially rejected its application for approval.
According to Dr. Steven Nissen, chairman of cardiology at the Cleveland Clinic, Arcoxia should not receive FDA approval.
"Showing that you're not inferior to diclofenac doesn't make this an approvable drug," he said.
The most common heart ailment examined in the study was heart attack, though the researchers also noted that patients taking 90 mg doses of Arcoxia experienced more edema -- fluid retention -- and a higher rate of heart failure. Merck is seeking approval of 30 mg and 60 mg doses of Arcoxia to treat osteoarthritis.
However, critics of the drug say it would be unpopular, given its safety risks. Luis Alberto Garcia Rodriguez, author of an editorial that accompanies the study in the Lancet, said the study's design was flawed because it compared Arcoxia with a heart medication (diclofenac) with known heart risks. A better comparison would have been naproxen, which is safer for the heart, Rodriguez said.
"There is no clear evidence of which drug to choose," he said. "Based on these results, doctors won't feel too inclined to prescribe Arcoxia."
However, Arcoxia has already been approved in 62 other countries, and earned Merck $218 million in sales last year.
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