A soon to be published study by Oxford University has found that Vioxx, a dangerous painkiller pulled from the market in 2004, may have caused heart attacks and strokes much sooner than originally believed. Researchers dispute previous claims by finding that half the cardiovascular events linked to Vioxx in the study occurred within the first 12 months of the drug’s use.
Manufacturer Merck & Co. has claimed that patients must be on Vioxx for at least 18 months before the acknowledged side effects could occur. Oxford’s study challenges this notion, finding that 16 out of 23 incidents of heart attack and stroke occurred in Vioxx patients, and half of those were within the first 12 months.
These results not only conflict with other major studies supported by Merck, but they could potentially affect the thousands of lawsuits facing the manufacturer in the wake of Vioxx’s withdrawal. The study was part of a prepublication version of the New England Journal of Medicine that was circulated for review, and should see print in the near future.