Why did Merck take Vioxx off the market?
Merck pulled its best-selling arthritis drug off the market based on data indicating the drug increases the risk of heart attack and stroke among users. Merck announced the immediate, voluntary worldwide withdrawal after a three-year colon cancer clinical trial with 2,600 patients revealed that 18 months after patients started taking Vioxx, test results showed an increased risk of heart attacks and other cardiovascular complications. 84 million people have used Vioxx since 1999.