(Orlando, FL) -- A new study is casting doubt on the effectiveness of a popular cholesterol-lowering medication.
A team of doctors found that Merck Research Laboratories' Zetia was significantly less effective at reducing artery plaque than Abbott Laboratories' Niaspan in a 14-month study of around 360 patients with heart disease or high risk of heart problems.
The study sponsored by Abbott is the second in two years to question the effectiveness of Zetia's key ingredient, ezetimibe.
Details appear in the online version of the "New England Journal of Medicine."