Niaspan ( Abbott) vs Zetia ( Merck): And the winner Is...NIASPAN

July 9 (Bloomberg) -- Merck & Co. fell in New York trading after researchers halted a study comparing Abbott Laboratories’ cholesterol drug Niaspan with Zetia, sold by Merck and Schering- Plough Corp.

The researchers said there were no safety concerns and chose to stop the study, called Arbiter 6 Halts, after a “prespecified, blinded interim analysis,” according to a posting in the National Institutes of Health’s clinical trials database. Abbott doesn’t know why the study was ended early and wasn’t involved in the decision, said Elizabeth Hoff, a spokeswoman for the company, based in Abbott Park, Illinois.

The study may have shown Niaspan was more effective at unclogging arteries than Zetia, according to analysts from Natixis Bleichroeder Inc. and Wells Fargo Securities LLC. A finding favoring Niaspan may further erode sales of Zetia, which fell 22 percent in the U.S. last year after studies, said Jon Paul LeCroy, an analyst with Natixis, who downgraded Merck today.

“We are now assuming that this trial significantly favored Niaspan and, as a result, we are decreasing our sales estimates for both Zetia and Vytorin,” LeCroy said. “If this trial favors Niaspan, it would be the third blow against Zetia. We would expect Zetia and Vytorin prescriptions to show further declines.”

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