The study provides more evidence on the risks of Vioxx, the arthritis drug removed from the market last year. The report appears in this week's issue of The Lancet.
Last year, a study showed that patients taking higher doses of Vioxx (more than 25 milligrams daily) had triple the risk of heart problems, including heart attacks and sudden deaths. The drug was voluntarily pulled from the market in September 2004.
In this newest study, researchers back up those results -- finding higher risks of serious heart disease among Vioxx users, especially those taking higher doses of the Cox-2 drug.
An estimated 88,000 to 140,000 cases of serious heart disease in the U.S. are probably related to Vioxx, reports researcher David J. Graham, PhD, with the FDA's Office of Drug Safety.
The Data on Vioxx
Graham and his researchers analyzed data on 1.4 million members of Kaiser-Permanente in California. All patients took nonsteroidal anti-inflammatory drugs (NSAIDs), including Vioxx, between 1999 and September 2004.
They found 8,143 cases of serious heart disease (heart attacks and sudden deaths) during that time; almost one-third (2,210) were fatal. Researchers extrapolated these numbers to arrive at estimates for serious heart disease cases among Vioxx users in the U.S.
The researchers compared the risk of serious heart disease in patients taking Vioxx and other NSAIDs with a group of similar adults not taking these pain relievers. They also compared the risk of serious heart disease in people taking another commonly used Cox-2 drug -- Celebrex.
Compared with people taking Celebrex, those who took Vioxx -- at any dosage -- had nearly a 60% higher risk of serious heart disease.
- 25 milligrams or less of Vioxx daily had nearly a 50% higher risk of serious heart disease
- More than 25 milligrams of Vioxx daily had nearly four times the risk (few patients in the study took higher doses of Vioxx)
They also show that people taking Vioxx (at any dose) had a 35% higher risk of serious heart disease when compare to people who used other NSAIDs in the remote past.
Graham calls for greater caution regarding new drugs. "In the future, when trials show that a new treatment confers a greater risk of a serious adverse effect than a standard treatment, we must be much more careful about allowing its unrestrained use," he says.