Drug Study Questions Effectiveness of Merck's Drugs

The results of a highly-anticipated head-to-head cholesterol drug study further calls into question the level of effectiveness of Merck's blockbusters Zetia and Vytorin.

AP

Researchers report at the American Heart Association annual meeting in Orlando and in "The New England Journal of Medicine" that Abbott's Niaspan cuts dangerous plaque in the neck arteries, while Merck's Zetia and had no effect.

Both groups of patients also took a statin, the most popular type of cholesterol-fighting drug.

And in what doctors refer to as a paradoxical finding, while Zetia was better at lowering bad cholesterol, it did not reduce plaque levels.

In the clinical trial, the patients on Zetia also had significantly more heart attacks than those on Niaspan. There were nine so-called cardiovascular events in the Zetia group versus two in the Niaspan group.

The study authors write in NEJM, "We believe that prudent clinical practice currently favors the avoidance of ezetimibe (Zetia)...."

Merck says the study, which included slightly more than 200 people, was too small and was not rigorous enough to draw any firm scientific conclusions.

The drug giant is doing an 18,000-patient clinical trial to try to measure the heart effects of Zetia and Vytorin, but the results won't be known for at least a few years.

Merck also says the findings don't change the fact that Vytorin and Zetia are effective at lowering bad cholesterol.

Zetia and Vytorin, which is a combination of Zetia and the statin Zocor, are a $4-billion franchise for Merck. But sales have been falling since a  2008 study also raised questions about their effectiveness.

Abbott says it sold $215 million worth of Niaspan in the third quarter, an increase of more than 10 percent. It's a long-acting form of Niacin that's designed to reduce the flushing side-effect of the half-century old B vitamin.

Abbott paid for the study and the lead outside clinical researcher reports having received more than $10,000 in lecture fees from the company. He would not reveal exactly how much more.

"The ARBITER study is the first study showing that HDL-raising with Abbott's Niaspan on top of statin regresses atherosclerosis compared to an LDL-lowering strategy," said Eugene Sun, M.D, vice president, Abbott Global Pharmaceutical Development.

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