A report on Vioxx risks previously blocked by the Food and Drug Administration was published online Monday after the agency withdrew its opposition.
The study found that as many as 140,000 cases of heart disease in the United States and as many as 56,000 deaths were caused by the painkiller during the five years that it was on the market.
The study's findings were announced in August at a medical meeting in France and in a Nov. 18 Senate hearing by its lead author, Dr. David J. Graham of the FDA's Office of Drug Safety. Graham has been an outspoken critic of the FDA's regulatory policies for new drugs.
Similar to other research released last year, the study of 1.4 million patients found that low doses of Vioxx increased the risk of heart disease by about 50%, and higher doses increased it by 358%.
The study, published by the journal Lancet, was sponsored by the FDA and used data collected from patients of Kaiser Permanente California over a three-year period.
The report was accepted by the Lancet last year and scheduled for publication in November, about the same time that Graham was to testify to a Senate committee about the study's findings.
"On Nov. 16, I was ordered to withdraw the paper or 'face severe consequences' -- which I interpreted to mean that I would be fired," Graham said. "With a gun to my head, I called Lancet and withdrew the article."
Merck & Co. withdrew Vioxx from the market Sept. 30 after other studies linked the drug to increased heart attack risk.
The FDA cleared Graham's paper for publication this month.
The study identified about 40,000 people who used Vioxx, a million who used ibuprofen, 435,000 who used naproxen and 27,000 who used Celebrex, a drug from the same family as Vioxx known as Cox-2 inhibitors.
Graham's study found 8,143 cases of serious coronary heart disease and 1,508 deaths among all the painkiller users. The risk of heart disease and death was substantially higher for those taking Vioxx. No increased risk was associated with use of Celebrex.
Extrapolating the results on a nationwide scale, Graham and his colleagues estimated that Vioxx was responsible for 88,000 to 140,000 cases of heart disease.
In other developments Monday, Dr. William B. White at the University of Connecticut School of Medicine and his colleagues studied Vioxx, Celebrex and naproxen in patients with type 2 diabetes, hypertension and osteoarthritis. They reported in the Archives of Internal Medicine that Vioxx increased blood pressure significantly, but that the other two drugs did not. All gave similar pain relief, the report said.