Rofecoxib (Vioxx)
Rofecoxib is a COX-2 inhibiting drug developed to reduce pain without the gastrointestinal side effects of non-selective NSAIDs (non-steroidal anti-inflammation drugs). In May 1999, the drug was approved in the United States by the Food and Drug Administration (FDA) as as a treatment for osteoarthritis, severe back or joint pain in adults and for moderate to severe menstrual pain. The drug was marketed under the brand name of Vioxx by the pharmaceutical company Merck and Co.
On September 30, 2004, Merck voluntarily recalled Vioxx after an internal study proved increased risk of severe cardiovascular side effects among participants taking Vioxx.
Safety of Vioxx has been questioned since the results of the VIOXX Gastrointestinal Outcomes Research (VIGOR) became available in 2000. The study indicated a five-fold increase in the incidence of heart attack and stroke in those taking Vioxx vs. naproxen (Aleve), a traditional, non-selective pain reliever.
Traditional pain medications inhibit both COX-2 and COX-1 enzymes equally, while selective pain relievers block COX-2 only. Recent studies found that although Vioxx blocks pain caused by COX-2 enzymes, it may also disturb the beneficial balancing effect that the COX-2 enzymes have on the human heart and cardiovascular system. The disturbed balance may be the cause of increased rates of heart attack and stroke in patients taking the Vioxx. Read more on COX enzymes and COX-2 inhibitors.
It is estimated that at the time of the recall, as many as 2 million patients were taking the drug worldwide. Recent reports indicate that the cardiovascular side effects of Vioxx could have caused as many as 100,000 hospitalizations, 27,785 heart attacks and strokes and, possibly, as many as 10,000 to 15,000 deaths in the U.S.
Worldwide sales for Vioxx in 2003 were approximately $2.5 billion; sales in the United States amounted to $1.8 billion.