Vytorin’s Shortcoming a Boon for Statins
Disappointing Results of Vytorin Study Lead Doctors to Call for Return to Proven Cholesterol-Lowering Drugs
Vytorin Still Has Place in Treatment
If all those efforts fail, it's time to try Vytorin, the panel says.
Also, some patients taking statins, particularly at high doses, develop side effects such as muscle weakness and need alternatives, Smith says.
Study researcher Kastelein says that for the people he studied, all of whom had a genetic disposition to high cholesterol, high-dose statins plus Zetia is the only treatment that works.
"So what can I do? I certainly can't [take them off it]," he tells WebMD.
"I don't think we should take patients off it if they are doing well," agrees AHA past president Robert Bonow, MD, of Northwestern University in Chicago.
Why Did Vytorin Fail?
Kastelein says there are three possible reasons why Vytorin failed. One possibility is flaws in the technique used to measure plaque, but that’s "highly unlikely," he says.
Or it could be that the drug just doesn't work, but he says previous studies have shown that LDL is what counts, and it "doesn't matter how you reduced LDL," Kastelein says.
The most likely explanation, he tells WebMD, is that the participants did not have enough plaque buildup at the start of the study -- in other words, they were at too low of a risk to show benefit in a two-year study period.
Michael Davidson, MD, of the University of Chicago, says, "Lower LDL is better, and it doesn't matter how you get there.
"We don't feel Zetia is the reason ENHANCE didn't work. That is a possibility we have to list, but it is far less likely [than the population being too low-risk]," he says.
Krumholz maintains it's the pill. "It could also be that Zetia is just an expensive placebo and that its principal harm is it drains precious resources from our health care system and may lead people to use less of the drugs that we know are effective and beneficial," he says.
The bottom line, of course, is that no one knows for sure.
For now, all the doctors say they are eagerly awaiting the results of three larger ongoing trials, involving more than 20,000 patients, that are designed to show whether Zetia and Vytorin prevent more adverse events and deaths than statins alone.
Researchers said this week that they are expanding enrollment of the largest of those trials, IMPROVE-IT, to 18,000 patients, to ensure there are enough participants to show clear results. Those findings won't be available until about 2012.