Pfizer aborts cholesterol drug tests

04 December 2006

Drug giant Pfizer has rung down the curtain on the clinical trials and development of its a new generation of drug, torcetrapib, earlier hailed as a strong contender for the replacement of its anti-cholestrol Lipitor after its patent expires in 2011.

Pfizer suspended experiments with the drug abruptly on Saturday after an external panel monitoring the trial reported that clinical trial patients taking the compound in an international experiment, involving 15,000 patients, seemed to have increased the risk of death.

After initial studies showed positive results, Pfizer launched the latest study involving patients at high risk for heart attack and stroke. Half took torcetrapib along with the statin Lipitor; the other half took Lipitor alone.

Of the 15,000 people, 82 who took torcetrapib along with Pfizer's Lipitor died, which was higher than the 51 deaths among those who only took Lipitor.

The drug was supposed to help boost the levels of "good" HDL cholesterol — a new approach in the treatment of heart attacks and strokes. Of the number of new compounds designed to boost HDL levels being studied, torcetrapib was in the most advanced stage of development. These drugs work by inhibiting an enzyme called cholesterol ester transfer protein.

The abandoning of the drug is regarded as a major blow to the drug major as it had already invested an estimated $800 million in drug development, which, if approved, was expected to emerge a blockbuster as early as next year. Only early last week, Pfizer's CEO Jeff Kindler had said that the company hoped torcetrapib could be approved as early as next year.