Amgen Inc's cholesterol drug Repatha cut the risk of heart attacks and strokes by over 20 percent in patients with heart disease, but the extent of its benefits in the highly-anticipated study disappointed investors and shares fell 6 percent.

The FOURIER (Further Cardiovascular Outcomes Research With PCSK9 Inhibition in Subjects With Elevated Risk) trial--a multinational, phase 3, randomized, double-blind, placebo-controlled study--was created to evaluate whether treatment with evolocumab in combination with statin therapy compared with placebo plus statin therapy reduces cardiovascular events. The new data could begin to change that.

For now, "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 currently offered", said Lloyd-Jones. Results from a similar Praluent trial are expected later this year. On average, participants in the Fourier study were 69 years old and more than two-thirds were taking moderate statins to lower cholesterol.

"This is a game changer", said Dr. Kausik Ray, who presented the data at the ACC meeting. Six lipid-lowering trials randomized 4,449 patients, who previously had a heart attack or stroke or had extremely high baseline cholesterol levels and were on statin therapy, to receive either bococizumab (150 mg subcutaneously every 2 weeks) or placebo to determine the effects on LDL levels. But researchers didn't have evidence then that the drug could also protect against heart attacks or strokes. "The more important hurdle is the one that payers have imposed restricting access to these medicines", wrote analysts at the investment bank Leerink Partners in New York City, in a report released 15 March. 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.

Dr Marc Sabatine, from Brigham and Women's Hospital in MA and lead researcher on the study, presented the findings today (17 March) at the American College of Cardiology's (ACC) 66th Annual Scientific Session in Washington.

"As a clinician this is very big news".

"The drug was safe and well-tolerated", said lead study author Marc Sabatine, chair of cardiovascular medicine at Brigham and Women's Hospital in Boston.

Dr. Steven Nissen, chief of cardiology at Cleveland Clinic, who was not involved in this study but has led other Repatha trials, said expectations for more dramatic results were unrealistic.

The trial's primary composite goal added need for artery clearing procedures and hospitalization due to chest pains from angina.

And when the researchers looked at the most serious possible outcomes for heart patients - deaths, heart attacks and strokes - the study showed a 20 reduction of those events.

Inclisiran, a PCSK9 synthesis inhibitor created to lower cholesterol levels in the blood, was shown to significantly lower low-density lipoprotein cholesterol (LDL-C) while maintaining standards of safety and tolerability for every single patient in a clinical trial, a triumph in treatment for cardiovascular disease caused by high cholesterol. Earlier guidelines set an LDL target of 70 for such high-risk patients.