Amgen has presented clinical data indicating that its PCSK9 inhibitor Repatha could help to reverse heart disease by removing atherosclerotic plaques, showing for the first time that the effect of this class of drugs may go further than reducing cholesterol alone.

Findings of a Phase III imaging study, unveiled at the American Heart Association's annual conference, show that adding Repatha (evolocumab) to statin therapy resulted in statistically significant regression of atherosclerosis in patients with coronary artery disease (CAD), indicating the drug might offer a key advantage over statin therapy.

Patients taking Repatha experienced a 0.95 percent decrease versus baseline in percent atheroma volume (PAV), the proportion of arterial lumen occupied by plaque, compared with an increase of 0.05 percent versus baseline in those receiving statin therapy plus placebo.

"This study shows that maximal LDL-C reduction with Repatha can actually regress coronary atherosclerotic disease compared to statins alone," said Sean E Harper, executive vice president of Research and Development at Amgen. "In fact, nearly two-thirds of patients on Repatha in this trial, the vast majority of whom were already on high to moderate intensity statin therapy at baseline, experienced a reduction in plaque burden."

Also, while the study was not powered to assess effects on cardiovascular events, an exploratory analysis revealed that positively-adjudicated major cardiovascular events occurred in 12.2 percent of patients receiving Repatha and 15.3 percent in those receiving placebo.

Data from the FOURIER trial, which is assessing the drug's impact on the risk of cardiovascular death, myocardial infarction, hospitalisation for unstable angina, stroke, or coronary revascularisation in subjects with clinically evident cardiovascular disease, are expected in the first quarter of next year.

Amgen's cholesterol buster Repatha became the first PCSK9 inhibitor to receive a regulatory approval anywhere in the world in July last year, following a green flag from the European Commission.

Trials showed that the drug - a human monoclonal antibody that inhibits PCSK9, a protein that reduces the liver's ability to remove LDL-C, or 'bad' cholesterol, from the blood - reduced LDL-C by 55 percent - 75 percent versus a placebo, and by around 35 percent to 45 percent compared with ezetimibe (Merck & Co's Zetia), in patients with primary hyperlipidaemia and mixed dyslipidaemia.

Repatha is funded by the National Health Service for adults with primary hypercholesterolaemia or mixed dyslipidaemia to help reduce their risk of cardiovascular disease, as is Sanofi's rival PCSK9 inhibitor Praluent (alirocumab).