A combination medicine by Merck & Co. and Schering-Plough Corp. was more effective in helping high-risk patients achieve stringent, new lower cholesterol goals than Pfizer Inc.‘s top-selling Lipitor in a clinical trial.

Merck and Schering-Plough’s Vytorin decreased LDL, or so-called bad cholesterol, to a greater degree than Lipitor across a variety of doses, according to data to be presented at the American College of Cardiology scientific meeting in Orlando, Florida, on Tuesday.

At the most common low starting doses for the medications, Vytorin reduced LDL by 51 percent compared with 36 percent for Lipitor.

But perhaps more interesting to physicians was Vytorin’s impact in helping high-risk patients reach the new guideline of taking LDL levels below 100 and down to 70. High-risk patients are those with coronary heart disease or with risk factors such as obesity, diabetes, high blood pressure or smokers.

“Getting down to 70 is not easy for these patients,” said Dr. Christie Ballantyne of the DeBakey Heart Center in Houston and the study’s lead investigator. “Before last year, we didn’t look at getting down to 70, but now we do.”

The six-week head-to-head study of 1,902 people with High cholesterol had eight arms, comparing the LDL lowering effects of the two drugs at a variety of doses.

At the 40-milligram dose, Vytorin reduced LDL cholesterol by 59 percent compared with 49 percent for Lipitor in the subgroup of high-risk patients. In addition, 57 percent of high-risk patients taking Vytorin achieved an LDL level of less than 70 compared with 23 percent of the Lipitor patients.

Ballantyne said three drugs on the market now appear to be able to take patients down to an LDL level of 70 - Vytorin, Lipitor and AstraZeneca’s Crestor. Crestor has been dogged by safety concerns.

Vytorin, which was approved for sale in the United States last July, combines Merck’s popular cholesterol fighter Zocor with Zetia, a Merck and Schering-Plough drug that uses a different mechanism to lower LDL levels than the statins.

Lipitor and Zocor are both statins that inhibit production of cholesterol in the liver. Zetia works by blocking the absorption of cholesterol in the intestine.

The typical starting dose for Lipitor is 10 milligrams. For Zocor, or the Zocor component of Vytorin, it is 20 mg. All doses of Vytorin contain 10 mg of Zetia.

Although the study sponsored by Merck and Schering-Plough was designed to monitor LDL reduction, researchers observed greater increases in levels of HDL, or good cholesterol, in the Vytorin patients - 9 percent versus 3.8 percent at 40 mg.

Many researchers believe raising good cholesterol may be as important as lowering bad cholesterol in fighting heart disease.

Pfizer is currently testing Lipitor in combination with an experimental drug designed to raise HDL levels called torcetrapib. The company believes that combination pill may eventually outstrip sales of Lipitor.

###