More Evidence Links Celebrex to Heart Problems

A consumer advocate Monday accused Pfizer, the maker of Celebrex, of hiding the results of a study in which patients who took the drug were 3 times more likely to have a stroke, heart attack or other serious cardiovascular problem than those on a placebo.

Sidney Wolfe of Public Citizen’s Health Research Group had petitioned the Food and Drug Administration on Jan. 24 to ban Celebrex and Bextra, the only COX-2 inhibitor pain relievers still sold in the USA. Meanwhile, Kaiser Permanente has decided to stop dispensing Bextra at its California pharmacies because of cardiovascular safety concerns.

Merck withdrew Vioxx, its COX-2 inhibitor, Sept. 30 after a study found a higher risk of heart attacks and stroke in volunteers who took the drug compared with those on a placebo. Although some scientists believe all COX-2 inhibitors have a similar effect, Pfizer ran full-page ads in USA TODAY and elsewhere assuring patients that Celebrex was safe.

In a follow-up letter Monday, Wolfe told acting FDA commissioner Lester Crawford that he had just discovered an unfavorable Celebrex study, apparently posted the day he submitted his petition, on a clinical trials Web site run by the Pharmaceutical Research and Manufacturers Association, or PhRMA.

In a statement Monday, Pfizer said it did not hide the study. It said it was presented at a scientific meeting in 2000 and given to the FDA in June 2001. The study, which never ran in a medical journal, randomly assigned 285 Alzheimer’s patients to Celebrex and 140 to a placebo. When major cardiovascular problems were combined, those on Celebrex had a significantly higher risk.

On the PhRMA Web site and in its statement, Pfizer explained that the Celebrex patients were more likely to have cardiovascular disease risk factors than those on a placebo. But Wolfe says he’s skeptical, because the point of randomized trials is to eliminate patient differences that could affect the results.

Recent studies involving Celebrex have yielded conflicting results. An FDA-sponsored study posted in January on The Lancet Web site, as well as a Canadian study posted online Monday by the Annals of Internal Medicine, found a higher risk of cardiovascular problems in patients whose doctors prescribed Vioxx, but not in those getting Celebrex.

Also in December, the National Institutes of Health halted two studies in which participants were randomly assigned to take Celebrex or a placebo or, in one of the two, Aleve, the non-prescription brand of naproxen. One linked Celebrex to heart attacks and strokes; the other linked Aleve, not Celebrex.