House Of Pain – The Downfall of Vioxx

On September 30th, 2004, the FDA had the drug company Merck withdraw its anti-inflammatory pain medicine vioxx (rofecoxib). When Vioxx was withdrawn from the market, it represented the largest prescription drug removal in history! In this article, we will explain the differences between traditional NSAIDs (non-steroidal anti-inflammatory drugs) and the COX-2 inhibitors (like Vioxx), look back at what happened to Vioxx, and examine the evidence behind why it was taken off the market.

Traditional NSAIDs vs. COX-2 Inhibitors
Anti-inflammatory medications are one of the most commonly prescribed classes of medicines in the world. Traditional NSAIDs are medicines like ibuprofen, motrin, and naproxen. They are anti-inflammatory medicines that inhibit both COX-1 and COX-2 enzymes. One of the functions of COX-1 is to help maintain the lining of the stomach and intestinal tracts. COX-2 is responsible for mediating the body’s response to inflammation and pain. The COX-2 inhibitors, like Vioxx, do NOT inhibit COX-1 enzymes; they only block the COX-2 enzymes. The idea behind using the COX-2 inhibitors was that they would cause less gastrointestinal problems, like ulcers and acute bleeds.

A Brief History of Vioxx
In May 21, 1999, the FDA approved Merck to market Vioxx. The VIGOR (Vioxx Gastrointestinal Outcomes Research) study was the major source of data that Merck used to show the Vioxx had less gastrointestinal side effects than traditional NSAIDs. Naproxen was compared to Vioxx, and it was found that Vioxx created a lower percentage of stomach ulcers and intestinal (duodenal) ulcers (0.7 and 0.7%) vs. naproxen (2.0 and 1.0%). However, some troubling data came out of this study which showed that the patients taking Vioxx had a higher risk of heart attack or stroke when compared to naproxen (0.4% vs. 0.1%).

On February 8, 2001, the FDA Arthritis Advisory Committee met to discuss the potential cardiovascular risks of Vioxx. The result was that on April 11, 2002, one year later, the FDA made Merck include a warning about potential heart related risks to users of Vioxx. It wasn’t until more evidence came out of the APPROVe (Adenomatous Polyp Prevention on Vioxx) study, which looked at 2600 patients with colon polyps taking either Vioxx or a placebo that the FDA took action. This study was stopped early because 3.5% patients taking Vioxx developed heart attacks or strokes compared to 1.9% of the patients taking the placebo. So while Vioxx may have created slightly less stomch problems, it was causing more heart attacks and strokes – not a good thing.

The Money Trail
When Vioxx was withdrawn from the market this past September, over 80 million patients had taken this medication. Merck had spent 100 million dollars per year on direct-to-consumer marketing, flooding the public, and asking them to request Vioxx from their doctors. More than 10 million prescriptions were written each month for Vioxx in the United States. Annual sales were regularly over one billion dollars, with the most recent annual sale figure being 2.5 billion.

In Summary
The interesting fact in this saga is that in no study was Vioxx or other COX-2 inhibitors shown to be more effective than traditional NSAIDs in treating pain and inflammation. Rather, the COX-2 medicines were only shown to cause fewer gastrointestinal side effects. One last piece of interesting information is the fact that many people who take COX-2 inhibitors for arthritis pain or inflammation also may take a regular or baby strength aspirin to protect their heart. Taking the aspirin essentially negates the stomach and gastrointestinal effects of taking the COX-2 inhibitor. The evidence is still out on whether or not all COX-2 inhibitors have the potential to cause this greater risk of heart attacks or stroke. Just remember all medications have benefits as well as side effects, and it is important to be informed of both.