When Vioxx was approved in 1990 it immediately rose to number one on drug sales charts. Vioxx is a COX-2 selective nonsteroidal anti-inflammatory drug prescribed to relieve arthritis, acute pain in adults, and painful menstrual cycles. Because Vioxx only needs to be taken once every 24-hours and has low gastrointestinal side effects it was known as a wonder drug of its time.

On September 30, 2004, Merck & Co. announced a voluntary worldwide withdrawal of Vioxx due to safety concerns. In Vioxx test groups of more than 4,000 patients, Vioxx users suffered 101 serious cardiovascular events.

Recently other studies in patients taking Vioxx have also suggested an increased risk of cardiovascular events. FDA was in the process of carefully reviewing these results, to determine whether further labeling changes were warranted, when Merck informed the agency of the results of the new trial and its decision to withdraw Vioxx from the market.