Vioxx, the trade name of the generic drug rofecoxib, was approved by the U.S. Food and Drug Administration (FDA) in May 1999, for the treatment of osteoarthritis, menstrual pain and the management of acute pain in adults. On September 30, 2004 the manufacturer of Vioxx, Merck & Co., Inc. (Merck) announced that it was voluntarily withdrawing Vioxx from the market worldwide, due to increased risks of cardiovascular problems (including heart attack and stroke) in users of the drug.

A member of the family of non-steroidal anti-inflammatory drugs (NSAIDs), Vioxx does not cure arthritis or other causes of acute pain, but helps to address their symptoms as long as it is taken.

How NSAIDs Work

Although steroids are considered safe for brief use to reduce inflammation, when taken for longer periods they can cause serious side effects like weight gain, fluid retention often visible in the face, sudden mood swings, muscle weakness, blurry vision, increased body hair, osteoporosis (bone weakening), high blood pressure, stomach irritation, and/or glaucoma. Consequently, NSAIDs are used to reduce inflammation if steroids can be avoided.

Vioxx works by preventing the formation of "inflammatory" prostaglandins. These compounds are produced by the enzyme "cyclooxygenase 2," commonly referred to as "Cox-2," and are believed to cause pain and inflammation, as well as prevent blood cells from sticking together. Vioxx is part of a group of drugs known as "Cox-2 inhibitors."  Unlike other NSAIDs, Vioxx does not also block a second enzyme, commonly called "Cox-1," that monitors and maintains stomach tissue.  Since this protects the stomach lining, Vioxx has been promoted as being able to reduce pain and inflammation without also causing ulcers and gastrointestinal bleeding.

Vioxx: History of Clinical Studies

In August 2001, Vioxx was linked in a study by researchers from The Cleveland Clinic to an increase in the risk of blood clots, heart attacks and strokes. Their study was published in the Journal of the American Medical Association and was based on a review and analysis of previous clinical trials.

Additional study results and articles continued to appear in medical journals, further supporting suspicions about Vioxx's effect on the heart. In September 2001, the American Heart Association, the National Stroke Association and the Arthritis Foundation asked Merck to test whether Vioxx increased the risk of heart attack and stroke.