Longer term, Sabatine said, there could be a reduction in deaths as well. A group of patients was also treated with a placebo, and the results show that they were more likely to suffer a heart attack than patients taking Repatha. All of them were already receiving statin therapy.
The group which had received evolocumab experienced fewer primary endpoint events, compared to the placebo arm of the study, with 1,344 (9.8 per cent) compared to 1,563 (11.3 per cent) respectively. They followed-up these people for two years, from 2013 to 2015.
Sean Harper of Amgen which makes Repatha said it was "a game changer for high-risk patients". On the other hand, researchers didn't observe any effect on the rates of hospitalization for unstable angina, cardiovascular death or hospitalization for worsening heart failure, or death from any cause.
"We should still probably reserve these for the highest-risk patients where statins are not doing a good enough job, at least at the price they are now offered", said Lloyd-Jones.
"It's hard not to give that drug" to patients now that a benefit has been shown, said Baum, who consults for Amgen and Praluent's makers - Regeneron Pharmaceuticals Inc. and Sanofi SA. Instead, it had only been tested in laboratory trials.
Roxana Mehran, professor of medicine at Mount Sinai School of Medicine in NY, described the findings as "probably the most important trial here" at the ACC meeting, which is the largest annual gathering of cardiologists in the United States.
Results from the long-awaited Fourier trial, created to test Amgen's Repatha as a tool to cut cardiovascular risks, showed that the drug cut heart attack risks by 27% over the course of the study, which followed patients for an average of two years.
The researchers found an average decline of 59 percent in LDL levels among the 14,000 people in 49 countries who were put on the drug for 48 weeks, when compared with an nearly identical number of patients who received a placebo.
This treatment has not been approved for all kind of patients. The company already has some pay-for-performance deals with payers-including arrangements with Harvard Pilgrim and Cigna-that link the net price of Repatha to expected LDL cholesterol reductions. However, it has been created to target a protein in the liver with the name PCSK9.
Patients on the trial, who continued to take statins, were chosen to randomly receive either injections of evolocumab - 140 mg twice a month, or 420 mg once a month - or placebo injections.
In the United States, heart disease accounts for one in every four deaths, and kills more than 600,000 people every year. PCSK9 is a protein that targets LDL receptors for degradation and thereby reduces the liver's ability to remove LDL from the blood.
"My first thought is that even if the drug is really effective, the price has to come down in order to offer benefit ...to the health care system", she told CTV News.
Previous research had raised the possibility that evolocumab, sold under the brand name Repatha by Amgen, may have a damaging effect on memory and cognitive function. "It's remarkable to see such a large impact in reducing cardiac events given that this patient population was only on Repatha for about two years".
"With this trial, we now have definitive data that by adding evolocumab to a background of statin therapy, we can significantly improve cardiovascular outcomes and do so safely", said lead author Marc S. Sabatine from Brigham and Women's Hospital in Boston.