Vytorin, the controversial cholester found that patients taking Vytorin in the study were more likely to develop cancer.
Vytorin, which was developed and marketed jointly by Merck and Schering-Plough, was approved for use by the Food & Drug Administration (FDA) in 2004. Since it came on the market, Vytorin sales have reached $5 billion per year. Vytorin is a combination of cholesterol-lowering Zetia (ezetimibe) and the statin Zocor (simvastin). 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.
This latest Vytorin study – known as SEAS – was presented Monday in London by its primary researcher, Dr. Terje Pedersen of Ulleval University Hospital in Oslo, Norway. The study investigated the effects of Vytorn in patients with aortic stenosis. Aortic stenosis involves partial blockage of the aortic valve in the heart. Left untreated, it can progress to death from heart failure or cardiac arrest. Aortic valve replacement for severe symptoms is the second most frequent type of heart surgery. Apart from surgery, there is no medical therapy known to prevent or heal this condition
High levels of LDL (bad) cholesterol have been known to be associated with the development of aortic stenosis. The SEAS study is the first large-scale randomized trial to assess the effects of lowering LDL-cholesterol in patients with aortic stenosis. It included 1873 patients with mild to moderate aortic stenosis without symptoms who were not considered to have a clear indication for treatment with cholesterol-lowering drugs. Patients were randomly assigned to receive either intensive cholesterol lowering with Vytorin or matching placebo.
The researchers found that Vytorin was no better than placebo at lowering the risk of major cardiovascular events in patients suffering from aortic stenosis. Vytorin also failed to meet a secondary goal of improving aortic valve disease events, which included valve replacement surgery, hospitalization because of heart failure, and death related to heart.
Vytorin did meet the study’s secondary goal of reducing atherosclerotic disease, in which plaque builds up and blocks an artery. Events included in the study assessment were nonfatal heart attacks, the need for bypass surgery, and strokes.
According to the researchers a total of 158 patients enrolled in the study “were recorded with a serious adverse event attributed to cancer.” Of these events, 93 occurred among patents taking Vytorn and 65 in patients assigned a placebo. There were 39 cancer deaths among the Vytorin group, and only 23 among those taking a placebo.
Because the SEAS study was small, researchers said that they could not determine what role Vytorin played in the cancer incidents. In order to assess their relevance, the SEAS data have been provided to an independent academic group for combined analysis with data on cancer from the two other large trials of Vytorin, which are still in progress.
SEAS is the second study to cast doubt on the effectiveness of Vytorin. The ENHANCE study, which was released on January 14, showed that Vytorin was ineffective in preventing clogged arteries, and might actually increase plaque in some users. When ENHANCE was vetted during the annual meeting of the American College of Cardiology in March, doctors there recommended that it be used only as a last resort. “Our strongest recommendation is that people need to go back to statins,” said panel member Dr. Harlan Krumhotz.