Internal Merck & Co. e-mails and documents show the company knew for years that its popular pain reliever Vioxx posed serious risks of heart attack and stroke, The Wall Street Journal reported.
When it pulled Vioxx off the market in September, Merck said it was "putting patient safety first" but the Journal says company officials had fought for years to protect the highly profitable drug and to keep news of the health risks quiet.
Vioxx was a big moneymaker for Merck, generating about $2.5 billion in yearly sales.
In early 2000, Merck research chief Edward Scolnick e-mailed Merck colleagues that the health risks "are clearly there." But the company continued to publicly reject any link between Vioxx and increased health risks.
Older and cheaper pain relievers such as aspirin and naproxen, known commercially as Aleve, block the COX-1 and COX-2 enzymes that are involved in inflammation and pain. Blocking COX-1 enzymes can upset the stomach but research indicates it may also help prevent blood clots, the leading cause of heart attacks and strokes.
Vioxx blocks only the COX-2 enzyme, thus providing powerful pain relief with no stomach upset. But clinical tests have indicated that it also fails to protect against blood clots and may even cause additional clots to form.
As far back as 1997, the Journal says Merck executives and scientists were discussing the risk. One said flatly that unless patients taking Vioxx also took aspirin, "you will get more thrombotic events," meaning blood clots. But adding aspirin would increase the risk of stomach irritation, leading to what another Merck official called "a no-win situation," the Journal said.
Merck responded that the comments were taken "out of context" and denied that it had purposely endangered its customers. In a statement, Merck said it had acted "responsibly and appropriately" in developing and marketing Vioxx.
Merck shares fell as much as 7 percent to their lowest level in more than eight years after the report.
Merck withdrew the drug September 30 after a study showed that prolonged usage could double the risk of heart attack and stroke in patients who took it for 18 months. That left about 1.3 million Americans looking for a substitute.
Researchers say the number of patients who have had heart attacks or strokes as a result of taking Vioxx could range from 30,000 to 100,000.
