WASHINGTON - The blockbuster arthritis drug Vioxx was taken off the market yesterday by Merck & Co. in the largest voluntary drug recall in history after a study confirmed simmering concerns that it significantly raises the risk of heart attack and stroke.
Physicians recommended that patients taking the drug talk to their doctors and switch to other medications. Merck said it will set up a program to buy back unused supplies of Vioxx.
About 2 million people worldwide use Vioxx, and 84 million prescriptions have been filled since it came on the market with great fanfare in 1999. It is one of Merck's most important drugs, with $1.8 billion in U.S. sales in 2003 and global sales of $2.5 billion - 11 percent of the company's $22.49 billion in revenue that year. The market withdrawal slashed the company's stock price by more than $12 a share, reducing the company's market valuation by more than a quarter.
Merck said it received new information in a study last week showing that people who used the drug for more than
18 months had nearly twice as many serious cardiovascular problems as those on a placebo. The three-year study - aimed at showing that Vioxx could prevent the recurrence of polyps, which can turn cancerous, in the colon and rectum - was halted. During the study, 10 patients died, five who had been taking Vioxx and five who took dummy pills.
By Tuesday, the company had told the Food and Drug Administration it planned to withdraw the drug.
"We believe it would have been possible to continue to market Vioxx with labeling that would incorporate these new data," Merck President Raymond Gilmartin said. "However, given the availability of alternative therapies and the questions raised by the data, we concluded that a voluntary withdrawal is the responsible course to take."
FDA officials said they will begin additional study of three other painkillers in the class called Cox-2 inhibitors, which were hailed as near-miracle drugs when they came on the market in the late 1990s. The officials said the other Cox-2 drugs have not be associated with the same dangers of stroke and heart attack but acknowledged that no patients using them have been followed for 18 months, as was the case with Vioxx.
Although Vioxx was aggressively marketed after it won FDA approval in 1999 and has been used widely, serious health concerns were reported soon after it became available. The FDA required additional warnings to the drug's label in 2002, and several months ago received the abstract of another report describing heightened cardiac and stroke risks with Vioxx. FDA officials said they were studying those results when Merck contacted them earlier this week.
Patients who claim to have been harmed by Vioxx had filed more than 200 lawsuits before yesterday's announcement. Many of the cases have been consolidated into two major lawsuits in Los Angeles and New Jersey.
Merck officials stressed that there were no more than the expected number of deaths among the patients taking Vioxx in the new study, and they knew of no deaths that should be attributed to the drug.
But the company, long one of the industry's biggest and most respected, was clearly concerned about a potential onslaught of lawsuits.
"We have substantial defenses in these cases and will defend them vigorously," said Kenneth Frazier, Merck's general counsel.
Vioxx is the first prescription drug to be withdrawn since 2001, when the cholesterol-lowering drug Baycol was taken off the market. In the four years preceding that, 11 drugs were withdrawn for safety reasons.