Vioxx, one of the fastest-selling new drugs in the world, is likely to face review because a number of patients have experienced strokes and heart attacks after taking the medicine.
The heart attacks and strokes could be serious enough for the Food and Drug Administration to delay Merck & Co.'s plans to market Vioxx for rheumatoid arthritis (the drug is currently indicated for the treatment of pain and osteoarthritis). Vioxx was expected to achieve annual sales of $2 billion by the end of 2002.
Merck does not believe their drug causes heart attack or stroke. Rather, they believe that other medications for osteoarthritis have antiplatelet properties that are not present in Vioxx. The preventitive properties of other, similar, medications cause those medications to have lower stroke and heart attack instance. Vioxx does not cause heart attack or stroke, the other medications may just hold the two vascular complications at bay.
Preliminary data released by Merck in March of this year took note of a statistical anomily. Merck said patients using naproxen, a non-steriodal anti-inflammatory agent, while suffering more gastrointestinal side effects, had significantly fewer heart attacks and strokes than did the Vioxx group. The study did not include a placebo control group and is thereby considered to be flawed.
While it's too early to know what the FDA's reaction will be, the first standard action is to recommend revised labeling of a drug found to have new or additional side effects. For now, the FDA continues to believe that Vioxx is adequately safe and effective for its labeled uses. The FDA did issue a warning to Merck in August of 1999 asking them to remove an advertisment for Vioxx on the grounds that the advertisement misrepresented the indications and usage of the drug.
The FDA has become heavily criticized for it's handling of Rezulin and Fen-Phen. Increased scrutiny of the FDA may make it very hard for Merck to get Vioxx approved for any other indications other than pain and osteoarthritis.
For more information on Vioxx, you can visit Merck and Co.'s Web site. The FDA site is found at www.fda.gov. Currently, the FDA does not have any postings on the controversy.