Pfizer has been hit by a class action lawsuit in the USA, claiming that the world’s largest pharmaceutical firm broke the law by misleading investors about the safety of its top-selling painkiller, Celebrex (celecoxib).

The lawsuit, which was filed by law firm, Scott & Scott in a Connecticut court, notes that new prescriptions for Celebrex have slumped by 56% since a recent government-led study found an increased risk of heart attack and stroke in patients taking Pfizer’s drug [[20/12/04a]]. The law firm notes that the same problem led Merck & Co to withdraw its one-time competing drug, Vioxx (rofecoxib), from the market [[01/10/04a]]. It adds that Pfizer’s shares have begun to slide because of fears that, although the company has no plans to withdraw Celebrex from the market, it could see sales crippled as a result. Pfizer’s share price dropped 11% to $25.75 after the trial results were disclosed – wiping almost $25 billion off the firm’s market value.

The complaint alleges that, in a study conducted by Pfizer, the company found no increased heart risk with patients taking the 400mg per day Celebrex dose, and has defended its drug’s safety [[05/11/04b]]. However, the law firm notes that members of congress have since asked Pfizer for documents regarding Celebrex and its other pain offering, Bextra (valdecoxib). They want to know what information Pfizer had about the government-led study when it made the safety statements.