Celecoxib (Celebrex)
Celecoxib is another COX-2 inhibitor drug developed to reduce pain associated with arthritis and other chronic inflammatory illnesses. It was the first COX-2 inhibitor drug approved by the FDA for pain relief in December 1998.
Celecoxib is the least potent of the COX-2 inhibiting drugs. The selectivity ratio of celecoxib is only 30; that is, the drug inhibits COX-2 enzymes 30 times more than COX-1 enzymes. The selectivity ratio of Celebrex is considerably less than the 272 ratio of Vioxx, recently recalled by Merck.
The amount of selectivity for COX-2 enzymes may play a role in the side effects related to heart attacks and other cardiovascular problems. Needless to say, if the drug is taken in higher dosages, the harmful potency of the drug can increase with higher concentration of drug levels in the blood.
Recent government- and manufacturer-led studies, unveiled in late 2004, found that both celecoxib (marketed under the trade name of Celebrex) and valdecoxib (commercially sold as Bextra) may also induce myocardial infarction and cardiovascular side effects. These side effects are under intense investigation, but neither Celebrex nor Bextra have been recalled from the market. Pfizer plans to continue marketing the drug to doctors, but has stopped advertising the pain reliever to consumers.
Celebrex is Pfizer's best-selling drug. For 2003, sales in the United States were $2.5 billion, and $3.2 billion worldwide. Celebrex was initially marketed by Pharmacia, a pharmaceutical company purchased by Pfizer in 2004.