AstraZeneca's Crestor cholesterol drug slowed thickening in the neck arteries of people at low risk for heart attacks and strokes, but it failed to reverse thickening as researchers had hoped it would.
Thickening of arterial walls is a precursor to plaque buildup, which can lead to heart attacks and strokes. Crestor is approved primarily to reduce levels of bad cholesterol, but AstraZeneca hopes U.S. health regulators will approve expanding the product label to say it can improve atherosclerosis, or plaque buildup.
On its own, the new Crestor study probably won't support the wider use of Crestor and other statins by people at low risk for heart attacks and cardiovascular events. But further studies in this large population could support greater use.
"In our study, the agent not only slowed progression of disease, but also caused the disease to come to a complete halt," John Crouse, a heart specialist at Wake Forest University School of Medicine, said in an interview at the annual meeting of the American College of Cardiology. Results of the study were presented here Sunday and published online by the Journal of the American Medical Association.
Still, the new study's results weren't as compelling as a Crestor study presented at last year's ACC meeting. That study was in people with signs of heart disease who were at higher risk for future heart attacks and strokes. Crestor partially reversed the buildup of plaque in coronary arteries in these patients.
AstraZeneca has submitted data from both studies to the Food and Drug Administration and expects to hear by the end of the year whether they can support a label change regarding atherosclerosis, said James Blasetto, head of strategic development for Crestor.
60% Rise in Crestor Sales
Last year's study helped fuel a 60% rise in Crestor sales to more than $2 billion for 2006. Crestor and another fast-growing cholesterol drug, Vytorin, have been taking share away from the cholesterol-drug market leader, Pfizer's Lipitor, which is the best-selling drug in the world with $12.9 billion in sales last year. Vytorin is marketed by a joint venture of Merck & Co. and Schering-Plough Corp. The companies are in fierce competition to show new clinical data demonstrating the superiority of their respective products.
The new Crestor study, nicknamed Meteor and funded by AstraZeneca, tested a high dose of the drug in people at relatively low risk for coronary heart disease, but who had some thickening in the carotid artery as measured by ultrasound imaging. Doctors typically don't prescribe statins for such low-risk patients.
The 984 participants took either Crestor or a fake drug and underwent follow-up ultrasounds to determine changes in the thickness of the wall of their carotid arteries. Patients were followed for about two years.
In those on a placebo, the carotid artery wall thickened by about 0.013 millimeters per year. There was a decrease of 0.0014 millimeters in the Crestor group, but statistically it wasn't enough to demonstrate regression. However, the difference in growth between the Crestor and placebo groups was enough to demonstrate that Crestor significantly slowed progression.
The study also found Crestor was associated with a 49% reduction in bad cholesterol, or LDL, and an 8% increase in good cholesterol, or HDL.
The most common side effects in the study included muscle pain and back pain, but the rates of these events weren't significantly different between the Crestor and placebo groups.
To date there have been no data proving Crestor can reduce the incidence of deaths, heart attacks and other cardiovascular events. AstraZeneca is currently conducting trials to determine this.