Does Stopping Vioxx Stop the Risk?
Experts, Drug Company Officials Disagree About Long-Term Heart and Stroke Risk
May 12, 2006 - Do strokeand heart attackrisks linked to the drug Vioxx continue after people stop taking it?
Yes, some leading cardiologists say. No, says Merck, which made Vioxx until pulling the painkiller off the market in September 2004.
It's not a mere moot point. At stake is the continued safety of the many people who took the heavily promoted drug before its risks became known.
The battle is over new data from the APPROVe study. The Merck-sponsored study led to Vioxx's demise. It found that patients taking Vioxx during the first three years of the study had a 92% higher risk of stroke and heart attack than those taking an inactive placebo pill.
New "preliminary" data released yesterday by Merck show that in the year after stopping Vioxx, the 1,721 patients still had a 74% higher stroke/heart attack risk. During that year, 28 patients who had taken Vioxx -- and 16 patients who had taken placebo pills -- had a stroke or heart attack. Most of these events were strokes.
This difference isn't statistically significant, meaning it could be a chance finding. Merck says this means there isn't any risk to people who stop taking Vioxx -- at least, no scientifically proven risk.
Not so, says cardiologist Steve Nissen, MD, interim chairman of the department of cardiovascular medicine at The Cleveland Clinic.
"What this means is the relative risk of an event with Vioxx, even after the drug was stopped, was very similar to the risk while taking the drug," Nissen tells WebMD. "It has profound implications for patients. It means that patients who previously took Vioxx must be followed closely and must be made aware of their increased risk."
Debate Over Meaning of Data
Michael Farkouh, MD, an expert on the heart safety of the class of drugs to which Vioxx belongs, is director of cardiovascular clinical trials at Mount Sinai Medical Center. He largely agrees with Nissen.
"It is concerning there is an ongoing risk from Vioxx," Farkouh tells WebMD. "I would say the numbers are small, but they suggest an ongoing risk from Vioxx in those who stopped taking it. There appears to be this same increase in risk as seen while taking the drug. While the difference is not statistically significant, it is concerning."