Did the FDA know about the risk of heart attack and stroke when it approved Vioxx?
The FDA originally approved Vioxx in May 1999. The original safety database included approximately 5,000 patients on Vioxx and did not show an increased risk of heart attack or stroke. A later study, called VIGOR (VIOXX GI Outcomes Research), was primarily designed to look at the effects of Vioxx on side effects such as stomach ulcers and bleeding and was submitted to the FDA in June 2000. The study showed that patients taking Vioxx had fewer stomach ulcers and bleeding than patients taking naproxen, another NSAID. However, the study also showed a greater number of heart attacks in patients taking Vioxx. The VIGOR study was discussed at a February 2001 Arthritis Advisory Committee and the new safety information from this study was added to the labeling for Vioxx in April 2002. Merck then began to conduct longer-term trials to obtain more data on the risk for heart attack and stroke with chronic use of Vioxx.
