Pfizer under pressure

Pressure is mounting on Pfizer to make clear any safety risks associated with its COX-2 inhibitor, Celebrex, after US consumer group Public Citizen accused the company of trying to hide a five-year-old study linking the drug with an increased risk of heart attack and stroke in patients.

The 1999 Alzheimer's study, posted on a website run by the US pharma industry association PhRMA (Pharmaceutical Research and Manufacturers of America), revealed that patients taking Celebrex had 3.6 times greater occurrence of a serious heart event, compared with those on placebo.

The accusation follows hot on the heels of last week's Public Citizen petition urging the US Food and Drug Administration (FDA) to withdraw Celebrex and fellow arthritis drug Bextra from the market as it believes the risks are too great.

Dr Sidney Wolfe, health unit director at Public Citizen, said Pfizer had posted the study results on the site only in recent weeks.

ìThere is no excuse for this study not being made more public,î he said. ìIt's a clear signal that I would have loved to have known about four years ago.î

In a statement, Pfizer acknowledged that people taking Celebrex suffered more cardiovascular problems than those taking a placebo but said that the group taking its drug had a greater number of medical conditions than the placebo group, potentially confusing comparisons.

'Because of this marked imbalance in the health of participating patients, definitive conclusions about cardiovascular risk cannot be drawn from this study,' the statement read.

Dr Gail Cawkwell, Pfizer's medical team leader for Celebrex, said the study's importance should not be overstated: ìMany other trials have shown that Celebrex is safe, and that the medicine is an important treatment for arthritis patients.î

Lancet dataÖ

Pfizer's case to support Celebrex was bolstered just last week when new data published in the Lancet indicated that the cardiovascular risk factors attributed to Merck's Vioxx could not necessarily also be attributed to Celebrex.

Dr David Graham, of the US Food and Drug Administration's Office for Drug Safety, fought to publish his data after the FDA threatened him with dismissal, he noted, if he were to go ahead without its permission.

About 25 million people worldwide have taken Celebrex since it was launched in 1999 and the drug amassed sales of $3.3bn last year.

Separately, Pfizer (which tied up with Pharmacia in 2003) has announced it is to cut 1,000 UK jobs following a post-merger review of its business worldwide. The company said it would shed 400 jobs at its plant in Sandwich, Kent and sell its operation in Morpeth, Northumberland, which currently employs 571 people.