Pfizer’s experimental compound torcetrapib did not slow progression of plaque buildup in the coronary arteries, despite raising HDL or “good” cholesterol, a study showed.
Cleveland Clinic researchers, reporting results of the ILLUSTRATE study at the American College of Cardiology (ACC) in New Orleans, said that a torcetrapib/atorvastatin combination increased good cholesterol and lowered bad cholesterol in patients but substantially raised blood pressure and failed to slow the buildup of plaque.
“It is yet to be determined if this failure represents a problem unique to torcetrapib or predicts a lack of efficacy for the entire class of similar drugs,” said Steven Nissen, lead trial investigator, in a statement.
Nissen, chairman of cardiovascular medicine at Cleveland Clinic, told Bloomberg he had this advice for other companies with so-called CETP inhibitors in their pipelines, which include Bayer, Roche, Merck and Pfizer: “Now, if we go forward with similar drugs, we should do so in smaller-scale trials, monitored meticulously. We inch our way forward and see if we can't get out of this pickle.”
ILLUSTRATE, which involved use of an ultrasound probe to measure the change in plaque, may not have explained why torcetrapib proved ineffective at unclogging arteries. But Pfizer expects to have analyzed all its torcetrapib data by year’s end, and findings from that trial, called ILLUMINATE, may identify the reason the drug failed and if that problem was unique to the compound.