Vytorin takes a big hit
Study finds the cholesterol drug doesn't slow plaque growth.
By Washington Post
Published January 15, 2008
WASHINGTON - A popular cholesterol-lowering drug failed to help slow the buildup of artery-clogging plaque in a long-awaited study, the companies that market the medication said Monday, raising questions about whether its use should be limited.
The drug, Vytorin (a combination of Zetia and Zocor), also did not reduce the thickness of plaque lining artery walls, a significant disappointment for the manufacturers. The results will add to the growing concern over Zetia and Vytorin.
"Obviously we would have preferred a more favorable result," said Skip Irvine, a spokesman for Merck/Schering-Plough Pharmaceuticals, a joint venture between the two companies that markets both Zetia and Vytorin.
Other experts said the findings mark a major blow for the medications.
"This is stunning," said Steven Nissen, a Cleveland Clinic cardiologist who was not involved in the research. "I do not believe it should be used as a first-line therapy. It should only be used as a last resort. That's a stunning reversal for what was previously one of the fastest-growing cholesterol-lowering medications being used."
The companies disputed Nissen's conclusions, saying the study showed again that Zetia was highly effective at lowering cholesterol levels, by 15 to 20 percent in most patients.
The companies are sponsoring another large study aimed at evaluating the drug's ability to prevent heart attacks and strokes. That study is expected to be completed in 2011, Irvine said.
After their approvals in 2002 and 2004, Zetia and Vytorin quickly became popular, and their use has continued to grow, according to IMS Health, a health care information company.
Previous studies have shown Zetia and Vytorin are effective at lowering cholesterol, but other medications that do this have been shown to have additional benefits, such as slowing the buildup of plaque or sometimes even shrinking it, as well as reducing the risk of heart attacks and strokes and lowering mortality rates.
The new company-sponsored study was the first attempt to demonstrate Vytorin's ability to slow the progression of heart disease. It involved 720 patients in Europe suffering from a genetic condition that causes very high cholesterol levels. About half of the patients received Vytorin, and the other half got Zocor alone.
After two years, ultrasound measurements of plaque build-up in neck arteries found no significant difference between the groups, and indicated that those receiving Vytorin may have experienced slightly more build up.
"This is as bad a result for the drug as anybody could have feared," Nissen said. Millions of patients may be taking a drug that has no benefits for them, raising their risk of heart attacks and exposing them to potential side effects, he said.
There were no signs that patients taking Vytorin were any likelier to suffer side effects or heart problems, but Nissen and others said the study suggests that the medications deny patients the additional benefits of drugs such as Lipitor and Crestor.
"Whenever you use an ineffective treatment it means you are denying them effective treatments," Nissen said.
The companies have come under criticism from cardiologists and members of Congress for failing to release the findings sooner. They completed the trial in April 2006 and planned to release the findings by March 2007.
Both companies' stocks were down in trading Monday, with Merck's shares down 77 cents to $59.78, and Schering-Plough's down nearly 8 percent to $25.52. Zetia and Vytorin are important contributors to both companies' profits, especially to Schering, which is smaller and less profitable than Merck.
Analysts estimate that 70 percent of Schering's earnings depend on the drugs, and Merck is trying to repair its reputation after withdrawing the painkiller Vioxx from the market in 2004.
Information from the New York Times was used in this report.
What the findings mean
There were no signs that patients taking Vytorin were more likely to suffer side effects or problems, but Steven Nissen, a Cleveland Clinic cardiologist not involved in the research, and others said the study suggests that prescribing the drugs denies patients the benefits of drugs such as Lipitor, Zocor and Crestor. Patients should not be prescribed Zetia unless all other cholesterol drugs have failed, he said.
About the drugs
Vytorin and Zetia are among the most commonly prescribed cholesterol-lowering drugs.
Zetia: Approved in 2002, about 14-million prescriptions were written in 2006.
Vytorin: About 70 percent of patients who take Zetia do so in the form of Vytorin, which is a combination of Zetia and Zocor. Approved in 2004, about 18-million prescriptions were written in 2006.
[Last modified January 15, 2008, 01:20:11]
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