Vytorin, developed and marketed jointly by Merck and Schering-Plough, is a combination of cholesterol-lowering Zetia and the statin Zocor. Statins like Zocor reduce the amount of cholesterol produced by the liver, while Zetia lessens the amount of cholesterol in food that is absorbed in the intestines. High cholesterol levels put a person at risk of developing clogged arteries. It was thought that by using Vytorin to reduce both sources of cholesterol, the amount of artery clogging plaque would also be reduced.
A long-awaited study on the effectiveness of Vytorin called ENHANCE was finally released by Merck and Schering-Plough on January 14, 2008. ENHANCE had been designed to show whether Vytorin was more effective than Zocor alone in preventing progression of atherosclerosis in the carotid artery, which is in the neck. Such plaque buildup is a major risk factor for heart attacks and stroke.
The ENHANCE study focused on a group of 720 patients with a rare condition predisposing them to high cholesterol. The patients were given either Vytorin or a high dose of simvastatin, the generic form of Zocor. The ENHANCE study found that Vytorin worked no better to reduce clogged arteries than a high dose of a less-expensive, generically available statin alone.
Since its approval by the Food & Drug Administration (FDA) in 2004, an average of 1 million Vytorin prescriptions have been written each year. Countless people have taken the expensive drug believing it would reduce their chances of having a heart attack or stroke. Now it turns out that these Vytorin patients would have been just as well-served if they had simply taken a cheaper, cholesterol lowering statin.