An arthritis drug withdrawn on safety grounds last year probably killed many thousands of patients, a new study suggests. Researchers said the drug Vioxx may have caused between 88,000 and 140,000 serious heart problems in the United States alone since its introduction in 1999.

With heart disease death rates in the US running at 44%, many of these cases were likely to have been fatal, it was claimed. Vioxx, which has the scientific name rofecoxib, was prescribed to 400,000 patients in the UK. It was taken off the market at the end of September after a three year trial linked it to an increased risk of heart disease events.

The study published on-line today by the Lancet medical journal analysed data from 1.4 million Californians who had used various kinds of non-steroidal anti-inflammatory drugs (NSAIDs).

Among them were 27,000 patients who had been taking Vioxx, which belongs to a family of drugs known as Cox-2 inhibitors. A total of 40,000 were given another Cox-2 inhibitor, Celebrex, while others were taking ibuprofen or naproxen. The investigators, led by David Graham from the US Food and Drug Administration's Office of Drug Safety, found that 8,143 had suffered from serious heart disease between 1999 and last September.

Of these, 1,508 died suddenly from a heart problem.