Vioxx Scandal

Vioxx, manufactured by Merck & Co., belonged to a class of drugs called COX-2 inhibitors, designed to provide pain relief with fewer gastrointestinal side effects than traditional nonsteroidal anti-inflammatory drugs (NSAIDs). Approved by the FDA in 1999, Vioxx became one of the most prescribed medications in the United States, generating over $2.5 billion in annual sales at its peak.

Concerns about Vioxx’s cardiovascular risks emerged early in its commercial life. The VIGOR trial, completed in 2000, showed that patients taking Vioxx had five times the risk of heart attacks compared to those taking naproxen. Merck initially attributed this finding to naproxen’s protective effects rather than Vioxx’s harmful properties, an interpretation that many independent researchers disputed.

Internal company documents later revealed in litigation showed that Merck scientists had identified potential cardiovascular risks as early as 1996, before the drug’s approval. Despite mounting evidence of increased heart attack and stroke risks, Merck continued marketing Vioxx aggressively and did not adequately warn physicians and patients about the potential dangers.

The decisive evidence came from the APPROVe trial, designed to test whether Vioxx could prevent colon polyps. When data showed an 18-month doubling of cardiovascular events among Vioxx users, Merck voluntarily withdrew the drug from the global market on September 30, 2004. The company claimed this was the first definitive evidence of the drug’s risks, despite years of earlier warning signals.

Studies estimated that Vioxx may have caused between 88,000 and 140,000 excess cases of serious heart disease, including heart attacks and sudden cardiac deaths, during its five years on the market. The FDA faced criticism for its role in approving and monitoring the drug, with some agency scientists claiming their safety concerns had been suppressed by management.

Merck faced approximately 60,000 lawsuits from patients and families who claimed Vioxx had caused heart attacks, strokes, or deaths. In 2007, the company agreed to a $4.85 billion settlement to resolve the majority of these claims, one of the largest pharmaceutical settlements in history. The scandal prompted calls for reform in drug safety monitoring and clinical trial transparency.