Pfizer Bextra

Valdecoxib Bextra Pfizer, Inc. Cox-2 inhibitor 11/1/2002 4/7/2005 2.5 years Serious and potentially life-threatening skin reactions (Unavailable)... 

Valdecoxib (Bextra Pfizer), a second COX-2 specific inhibitor NSAID was taken off the market a few months after Vioxx. In addition to a higher risk of serious skin toxicity, pahents given Vioxx after Coronary Bypass Surgery had a higher rate of myocardial infarchons. 

Drugs specifically designed for COX-2 selectivity have been marketed quite successfully, especially in the United States. The drugs that were part of this litigation were celecoxib (Celebrex ) and valdecoxib (Bextra ). COX-2 selective inhibitors have been shrouded in controversy since their use has been in some cases linked with increased risk of heart attacks and stroke. Celebrex and Bextra were both marketed by Pfizer, but Bextra was pulled from the United States market in 2005 out of safety concerns. The COX-2 selective inhibitor rofecoxib (Vioxx ) was marketed by Merck and was voluntarily pulled from the market by Merck in 2004. Celebrex remains on the market, and worldwide sales in 2007 were over 2 billion. 

The 850 patent described the COX-1 and COX-2 enzymes as well as assays useful for distinguishing whether a compound was a selective inhibitor for the COX-2 enzyme. The 850 patent also described methods of using COX-2 selective compounds as well as their formulation, routes of administration, possible effective doses, and suitable dosage forms. On the day that the 850 patent issued, the University of Rochester sued Pfizer, G. D. Searle, and related parties in a federal district court alleging that Pfizer s marketing of Celebrex and Bextra infringed several claims of the patent (including claim l).22... 

Both Celebrex and Bextra were developed by Searle, which was subsequently purchased by Monsanto. Monsanto later merged with Pharmacia and Upjohn, and the resultant company later merged with Pfizer. 23 University of Rochester v. G.D. Searle Co., 249 F.2d 216 (W.D. N.Y. 2003). The District Court also held the claims to be invalid due to lack of enablement, an issue we will discuss further later in this chapter. 

The diaryl pyrazole derivative celecoxib (Celebrex /Pharmacia, Pfizer), the fiiranone derivative rofecoxib (Vioxx /Merck), and the isoxazole derivative valdecoxib (Bextra /... 

A similar fate befell a series of other coxibs as well These, like Valdecoxib (Bextra ) had to be withdrawn from the market by Pfizer, or, like parecoxib (Pfizer) or etoricoxib (Merck), did not obtain regulatory approval in major markets at all (Fig. 5.89). 

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