Pfizer shares slip 2% on concerns that key drug candidate may raise blood pressure

Concerns were raised about Pfizer's pipeline after preliminary trial results showed that its star drug candidate increased patients' blood pressure. The USA-based world drug giant is conducting a Phase III study of its megablockbuster Lipitor (atorvastin) as a fixed-dose combination with torcetrapib, a compound believed to raise high-density lipoprotein, or good cholesterol, which is considered important in the role of preventing heart disease.

On October 31, shares in the New York-headquartered firm fell 2.02%, to close at $26.65, after the American Heart Association released an abstract on the Phase III study which is evaluating the two drugs in patients with heterozygous familial hypercholesterolemia.

Although the combination cholesterol therapy significantly raised HDL cholesterol 56%, and cut low-density lipoprotein cholesterol, or bad cholesterol, 27% versus atorvastatin alone, the HeFH study also showed that patients in the torcetrapib/atorvastatin group experienced an average increase in systolic blood pressure of about two millimeters versus atorvastatin monotherapy. Data from the HeFH study, in patients with an increased risk of heart disease, will be presented at the American Heart Association's annual scientific sessions on November 15.