WASHINGTON, April 7: US health officials on Thursday asked Pfizer to withdraw arthritis drug Bextra from the market due to potential health risks, and ordered new warning labels for others in a similar class of drugs, including Pfizer’s Celebrex.

The Food and Drug Administration announced the changes on rules for the so-called COX-2 medications used for pain and arthritis, requiring warnings for a risk of heart problems and gastrointestinal bleeding.

The FDA said Pfizer agreed to a request to withdraw Bextra (valdexocib) from the market “because the overall risk-versus-benefit profile for the drug is unfavourable.”

Additional warning labels will be required for other painkilling medications sold by prescription or over the counter, warning of potential risks, the FDA said in a statement. These include widely used medications such as ibuprofen, an aspirin substitute.

Pfizer said in a statement it would work with the FDA on new warning labels for Celebrex.

“Pfizer and the FDA plan further discussions regarding the precise content of the Celebrex label,” the company said. “Pfizer also reaffirmed its commitment to conduct additional long-term clinical studies evaluating the benefits and risks of Celebrex.”

The company said it agreed to withdraw Bextra even though its cardiovascular risk “could not be differentiated” from other painkillers, since it was found to have an “increased risk of rare but serious skin reactions” that “warrants its withdrawal from the market.”

The company will also suspend Bextra sales in the European Union and is holding talks with regulators in other parts of the world.

Pfizer, however, said it “respectfully disagrees with FDA’s position regarding the overall risk/benefit profile of Bextra.”

But it said it agreed to suspend sales “in deference to the agency’s views,” adding that it would “explore options with the agency under which the company might be permitted to resume making Bextra available to physicians and patients.”

“For now, patients should stop taking Bextra and contact their physicians about appropriate treatment options,” Pfizer said.

The re-examination of cardiovascular risks of the so-called COX-2 drugs began after Merck voluntarily withdrew its arthritis painkiller Vioxx from the market in September 2004.

An FDA advisory panel of experts earlier this year narrowly agreed that Vioxx could be sold, but it was unclear whether Merck, which faces massive litigation, would attempt to reintroduce the drug. Thursday’s FDA statement said the agency “will carefully review any proposal from Merck for resumption of marketing of Vioxx.”

Vioxx, Celebrex and Bextra have been widely prescribed for arthritis and severe pain but have all come under fire recently for being linked to a higher incidence of cardiac problems in some patients.

All three drugs were determined by an FDA panel of experts to cause increased heart risks.—AFP