The long-awaited IMPROVE-IT trial was presented last month at the American Heart Association Scientific Sessions. Here are the presentation slides:
IMPROVE-IT was a trial that tested the ability of ezetimibe (Zetia) to lower the risk of heart attacks and strokes when added to simvastatin. See Larry Husten’s background post here, and if you type “ezetimibe” in the search box on this blog or on the Gooznews blog, you will find some previous posts of mine relating to ezetimibe. I admit I was a bit surprised that the trial was positive. I was expecting it to be negative, based on the negative results of the ENHANCE trial. Still, the benefit was small, a 6.4% reduction in risk of the primary endpoint (composed of cardiovascular death, heart attack, unstable angina requiring hospitalization, coronary revascularization, and stroke). In the high-risk trial participants — all patients who had been hospitalized for acute coronary syndrome within the 10 days before randomization — this translated to a 2% absolute benefit over 7 years. Of note, there was no reduction in all-cause or cardiovascular mortality.
I only want to make a few comments now, but I intend to write more when the trial is published. First, a 6.4% reduction is risk is a very small benefit, and many people would only consider that reduction in risk meaningful in a high risk population. Second, it is regrettable that we had to wait 12 years after the drug’s approval to find out whether it improves outcomes.
Here are great summaries by Larry Husten and Matt Herper. And here is a video of Harlan Krumholz giving his take on the results.
Addendum, May 5, 2015: Unfortunately, the GoozNews blog is no longer up on the web. I asked Merrill Goozner what happened and he said he decided to stop paying the annual fee for the website. So the posts I wrote on ezetimibe for GoozNews are no longer up.