• E-mail
• Print
• Comment
• Font Size
• Digg
• del.icio.us
• Discuss article

Vioxx Causes Double Risk For Heart Attack And Stroke

Posted on: Tuesday, 14 October 2008, 14:49 CDT

Researchers said on Monday that a long-term analysis of people who took the arthritis drug Vioxx confirms it doubles the risk of strokes and heart attacks, but this risk goes away a year after people stop taking it.

They also said other drugs in the same class of painkillers known as Cox-2 inhibitors may cause similar harm.

"The good news is the data suggests that the risk doesn't persist forever. The risk goes back toward normal after a year of follow up," said Dr. Robert Bresalier of the M.D. Anderson Cancer Center at the University of Texas, whose study appears in the journal Lancet.

In 2004, safety data from this same study set off alarms that Vioxx increased the risks of heart attacks and stroke, prompting drug maker Merck & Co Inc to withdraw the popular painkiller from the market.

Last year, Merck inked a $4.85 billion deal to settle thousands of claims for heart attacks, strokes and deaths allegedly caused by the drug. The original study, funded by Merck, was meant to determine whether Vioxx could prevent polyps that raise the risk of colon cancer.

Bresalier and colleagues published a 2005 analysis in the New England Journal of Medicine suggesting that it took 18 months for the drug to increase the risk of heart attacks and strokes, a time frame that played a prominent role in Merck's legal defense of Vioxx.

A correction was later posted on the journal’s Web site, saying the difference was not statistically significant. Bresalier said the new analysis, done with independent statisticians, suggests the risk occurs early and persists.

"This data shows you can't precisely determine the timing of the risk. It does appear to start relatively early," he said.

The study examined the effects of three years of treatment with Vioxx, or rofecoxib, in 2,587 patients. Patients were checked for side effects while on the drug and two weeks after they stopped. It includes one-year follow-up data on patients who stopped taking the drug because of heart side effects.

Bresalier said, in essence, the relative risk remained about the same.

In the study, people who took Vioxx had about the double the risk of having a heart attack or stroke than those who took a dummy pill, he said.

The overall findings were consistent with the original study, but all patients were able to be followed after they stopped taking the drug and the analysis was not able to take into account other heart risks, Merck said.

Merck issued a statement saying the research "using limited data from a prematurely terminated study needs to be interpreted very cautiously and in the context of the rest of the data from the extensive clinical development program for Vioxx."

However, a number of studies since the initial safety warning on Vioxx suggest other Cox-2 inhibitors, including Pfizer Inc's Celebrex, or celecoxib, and non-steroidal anti-inflammatory drugs (NSAIDS) such as ibuprofen, also carry a higher risk of heart trouble, Bresalier said.

"I think the preponderance of data now does suggest this is a class effect," he said.

Cox-2 drugs were designed to be safer replacements for NSAIDS, including aspirin and naproxen, which can cause deadly gastrointestinal bleeding.

"There seems to be an increased risk for most if not all non-steroidal anti-inflammatory drugs. That doesn't mean these aren't good drugs. Its just there is some increased risk we need to be aware of," he said.

Before the arthritis and chronic pain pill was withdrawn from U.S. drugstores almost four years ago, Vioxx had generated sales of $2.5 billion a year. Pfizer's Celebrex has remained on the market.

---

On the Net:

• M.D. Anderson Cancer Center
• Lancet

Source: redOrbit Staff & Wire Reports

More News in this Category