Pfizer acknowledged yesterday that a trial conducted in 1999 found elderly patients taking Celebrex were at greater risk for heart problems than those taking placebo.
The disclosure contradicts the company's earlier statements about the drug's safety.
Pfizer said last October that no study had ever shown a link between heart problems and its COX-2 indication Celebrex. The statement was made in response to Merck's withdrawal of its COX-2 drug Vioxx after its use was tied to heart problems.
In December, when a colon cancer study by the company pointed to an increased risk of heart attack and stroke and use of Celebrex, Pfizer said those results were unexpected.
But now Pfizer acknowledges the 1999 study, intended to see whether the drug could be used to treat Alzheimer's disease, found the number of Celebrex patients suffering heart attacks was almost four times that of those taking a placebo.
The study was never published and wasn't submitted to the FDA until June 2001, four months after the FDA conducted a major review of the safety of Vioxx and Celebrex.
Sidney Wolfe, director at the consumer advocacy group Public Citizen, said the trial's findings added further reason for the drug to be pulled from the market. On Monday, Public Citizen renewed its call for the FDA to immediately ban Celebrex and Pfizer's other controversial painkiller, Bextra.
But Gail Cawkwell, Pfizer's medical team leader for Celebrex told The New York Times yesterday that the study's importance should not be overstated. Many other trials have shown that Celebrex is safe and that the medicine is an important treatment for arthritis patients, she said.