The Food and Drug Administration has ordered Merck, maker of the blockbuster painkiller Vioxx, to issue a letter to doctors “to correct false or misleading impressions and information” stemming from the drug’s promotional campaign.
Merck’s marketing efforts, aimed mainly at doctors, have minimized Vioxx’s known and potential cardiovascular risks, the FDA wrote in an eight-page “warning letter” faxed Sept. 17 to Raymond Gil- martin, president and chief executive officer. The letter, signed by Thomas Abrams, head of the FDA’s Division of Drug Marketing, Advertising and Communications, was posted Friday on the FDA Web site.
Merck spokeswoman Chris Fanelle says her company will not comment on the letter until after it files a response to the FDA, which has set a deadline for Oct. 1. “We continue to stand behind the overall and cardiovascular safety of the product,” Fanelle says.
So far this year, the FDA has sent drug companies fewer than a dozen warning letters, which the agency reserves for activities that raise significant public health concerns. Pharmacia, maker of Celebrex, Vioxx’s main competitor, received one in February for violations similar to Merck’s.
The two drugs are heavily promoted to patients and doctors, and sales are expected to hit $6 billion this year. They are thought to be gentler on the digestive tract than other non-steroidal anti-inflammatory drugs, or NSAIDs, a group that includes aspirin and ibuprofen. However, the FDA has not yet given their makers permission to make that claim.
In the warning letters, the agency cautions both companies that the cited violations “do not necessarily constitute an exhaustive list.” The letters state that the FDA is continuing to evaluate other aspects of the companies’ promotional campaigns.
According to the Sept. 17 warning letter, a doctor under contract with Merck to present talks to other physicians, company sales representatives and a press release have minimized the possibility that Vioxx could increase users’ risk of heart attacks or strokes.
In a study of 4,000 patients, those on Vioxx were more than twice as likely to suffer a serious cardiovascular complication than those on naproxen, another NSAID.
The Vioxx patients were five times more likely to suffer a heart attack.
Merck’s promotional campaign has attributed that finding to naproxen’s protective effect, which is possible but unproven, the warning letter states. Meanwhile, it says, the company’s marketing efforts have ignored the possibility that Vioxx increases the risk of artery-clogging blood clots.
In February, an advisory panel recommended that the FDA require Merck to warn patients and doctors about an increased heart attack risk, but the agency has not yet asked the company to add that information to Vioxx’s label.
The warning letter also accuses the doctor under contract with Merck and company sales representatives of minimizing the risk of bleeding when Vioxx is taken along with Coumadin, a blood-thinning drug. And it says that the doctor promoted Vioxx for unapproved uses and doses and made unsubstantiated claims of superiority to other NSAIDs.