The painkiller Vioxx was withdrawn from the market in 2004 following a three-year study which showed it doubled the risk of heart attack and strokes in patients taking it for at least 18 months.
Vioxx belongs to a class of drugs known as COX-2 inhibitors which were originally designed to be a safer option to aspirin, ibuprofen and other non-steroidal anti-inflammatory drugs or NSAIDs, which can cause sometimes fatal stomach bleeding.
Now a correction to a key study on Vioxx has revealed the risk of heart problems was elevated throughout the time people were on the drug and did not just develop following 18 months of use of the drug as manufacturer Merck has stated.
The correction backs the claims of many doctors who believe the risks showed up after as little as three months of use.
Dr. Jeffrey Drazen, editor-in-chief of the New England Journal of Medicine who published both the study and the correction, worked with the authors to correct their original findings of the APPROVe trial which was published in March 2005.
He says heart attacks and strokes occurred more frequently after people had been on the drug for at least 18 months, but the actual harm occurred much earlier, and it is a subtle but critical point.