Mixed Results for Pfizer Combo Pill

Shares of Pfizer(PFE) skidded Tuesday after the pharmaceutical company issued mixed test results for a new drug to improve heart health.

The experimental drug lowers bad cholesterol and raises good cholesterol, but it also elevates blood pressure, according to preliminary results of a late-stage clinical trial.

By mid-afternoon, Pfizer's stock was off 74 cents, or 2.7%, to $26.45 on trading that was 50% higher than the average daily volume for the past three months.

The experimental drug combines Lipitor with the investigational compound torcetrapib. Pfizer is counting heavily on this combination pill, which features the bad-cholesterol-lowering power of Lipitor and the good-cholesterol-raising ability of torcetrapib.

Pfizer tested the combination pill vs. Lipitor in patients with heterozygous familial hypercholesterolemia -- a high level of bad cholesterol and a high risk of early heart disease. The combination pill raised good cholesterol by 56% and lowered bad cholesterol by 27% vs. patients taking only Lipitor. The study will be presented Nov. 15 at the American Heart Association's annual scientific convention in Chicago.

However, the combination pill also raised blood pressure by an average of about two millimeters vs. patients taking Lipitor. Systolic blood pressure, the upper number in a blood-pressure reading, reflects pressure of blood in arteries when the heart contracts. The lower number -- diastolic blood pressure -- measures pressure in arteries when the heart relaxes between beats.