Pfizer Inc. shares plunged on the new the cardiovascular risk associated with its painkiller Celebrex, a drug in the same class as Vioxx recently withdrawn from the market by Merck amid scandal about the heart attacks caused by its use. The study that showed cancer patients taking Celebrex in 400-milligram and 800-milligram doses were 2.5 times more likely to develop a fatal or non-fatal cardiovascular event sent the pharmaceutical giant’s stock down 15%.

Regulators on both sides of the Atlantic are now likely to swoop on the Cox-2 class of painkillers after the two resonating scandals involving Merck’s Vioxx and Pfizer’s Celebrex.

The U.S. Food and Drug Administration plans will look into the safety of the painkillers in an advisory committee meeting in 2005.

Pfizer stock dropped more than $4  in NYSE composite trading.