Well, analysts were right about that much-anticipated cholesterol drug study. Abbott Laboratories' Niaspan pill did indeed beat out Merck's Zetia at unclogging arteries, according to study results presented at the American Heart Association meeting yesterday. Cardiologists expect the data to boost niacin use--and serve as a further drag on sales of Zetia and its sister Merck drug Vytorin.
The trial, which tracked carotid artery narrowing in Zetia and Niaspan patients, was a small one with only 208 patients. Experts acknowledge that the data is hardly definitive. But high-profile cardiologists--even some who question the study methodology--said the trial was compelling enough to prompt doctors to move Zetia down on their lists of go-to drugs. "It's a big win for Niaspan, and yet another disappointment for Zetia," said Roger Blumenthal, who critiqued the new data for the New England Journal of Medicine (as quoted by Forbes).
As Forbes points out, the findings weren't limited to the ultrasound images; outcomes such as heart attacks and heart-disease-related deaths also were lower in the Niaspan patients. And when you look at the sum total of data on Zetia, there's just not enough on the positive side, cardiologists are saying. Niacin has proven helpful over 30 years of research, Dr. James Stein of the University of Wisconsin told the New York Times. "Compare that to Zetia where there is not a shred of evidence that it does anything good for blood vessels or heart disease."
Could this latest study raise more questions about the use of "surrogate markers" rather than outcomes in deciding whether to approve drugs? Well, as Merck officials are emphasizing in the wake of this study, Zetia has proven quite effective at cutting bad cholesterol. Bad cholesterol levels are considered a reliable surrogate marker of heart disease risk. But as Stein and others have pointed out, Zetia hasn't delivered on the outcomes side.
That's partly because Merck's big outcomes study won't be wrapped for a couple of years. But it's also proven the case in the ENHANCE study, which used imaging to gauge Zetia's effectiveness at keeping arteries clear, and at that it did no better than Zocor (simvastatin) by itself. And of course this latest study adds to the doubt. "This is the third strike," Dr. Steven Nissen of the Cleveland Clinic told the Washington Post.