Pfizer Drug in Development Increases HDL Levels, Study Finds
Torcetrapib, a drug being developed by Pfizer, "markedly increases" HDL, so-called "good" cholesterol, potentially offering a new tool to help combat heart disease, according to a study in the New England Journal of Medicine, the Philadelphia Inquirer reports. In the small 12-week study, which was partially funded by Pfizer, researchers followed 19 patients with HDL cholesterol below 40 milligrams per deciliter (McCullough, Philadelphia Inquirer, 4/8). HDL levels below 40 milligrams per deciliter are considered "an especially bad sign," while HDL levels above 60 milligrams per deciliter are considered good, the AP/Las Vegas Sun reports. The 19 patients took a 120-milligram torcetrapib pill once per day for four weeks (Johnson, AP/Las Vegas Sun, 4/7). Nine of the patients also took a standard dose of Pfizer's statin Lipitor because their LDL, or "bad" cholesterol, levels were too high (Philadelphia Inquirer, 4/8). For the patients taking just torcetrapib, HDL levels increased an average of 46%, to 46 milligrams per deciliter. For patients taking torcetrapib and Lipitor, HDL levels increased an average of 61%, to 47 milligrams per deciliter. In the third phase of the trial, six of the patients took the 120-milligram torcetrapib dose twice per day, and their HDL levels increased an average of 106% to 70 milligrams per deciliter. In addition, the study found that torcetrapib reduced LDL levels 8% when taken alone, and 17% when taken twice per day or with Lipitor. The study also found that torcetrapib reduced blood levels of triglycerides, another fat that contributes to heart disease, by about 20% (AP/Las Vegas Sun, 4/7). Studies suggest that each single point increase in HDL levels is matched by a 2% to 3% reduction in heart disease, the Detroit Free Press reports. Currently, the vitamin niacin is the only available treatment to raise HDL levels, but its effects are small and side effects such as hot flashes and itching bother many patients, the Free Press reports (Detroit Free Press, 4/8).
In an editorial accompanying the study, H. Bryan Brewer, who studies cholesterol at the National Heart, Lung, and Blood Institute, wrote, "The development of drugs to increase HDL ... represents an exciting new approach to the treatment of high-risk patients with cardiovascular disease." Study author Daniel Rader, who studies cholesterol at the University of Pennsylvania, said, "There is a huge unmet need for drugs that raise HDL" (Philadelphia Inquirer, 4/8). However, Rader added, "One of the big questions that we do have with this drug is: Will using it to raise HDL levels from normal to high actually reduce risk in people who are at high risk?" (AP/Las Vegas Sun, 4/7). Lead author Margaret Brousseau, an assistant professor of medicine at Tufts University School of Medicine, agreed, saying that only large-scale, long-term trials could answer that question. Kate Robins, a spokesperson for Pfizer, said that Phase III trials, which are needed to gain FDA approval for torcetrapib, are just beginning. She added that if approved, torcetrapib would only be marketed in combination with Lipitor (Detroit Free Press, 4/8). An abstract of the study is available online. An extract of the editorial is also available online.This is part of the California Healthline Daily Edition, a summary of health policy coverage from major news organizations. Sign up for an email subscription.