Intravascular study of PCSK9 inhibitor meets primary and secondary endpoints

Amgen announced Sept. 20 that an intravascular ultrasound study evaluating evolocumab (Repatha) met its primary and secondary endpoints.

The full results will be presented Nov. 15 at the American Heart Association scientific sessions in New Orleans. The study evaluated whether evolocumab modifies atherosclerotic plaque build-up in the coronary arteries of patients already treated with optimized statin therapy.

The GLAGOV trial enrolled 968 patients with coronary artery disease undergoing cardiac catheterization and receiving optimized statin therapy. Patients were randomized in a 1:1 ratio to receive 420 mg of evolocumab once monthly or placebo subcutaneous injections.

The primary endpoint was the change in percent atheroma volume (PAV) from baseline to week 78 as determined by intravascular ultrasound. The secondary endpoints included PAV regression, change in total atheroma volume (TAV) from baseline to week 78 and regression in TAV.

Amgen said that there were no new safety concerns with evolocumab. The incidence of treatment-emergent adverse events was similar between the groups, as well.

In August 2015, the FDA approved evolocumab, a proprotein convertase subtilisin kexin type 9 inhibitor intended to reduce low-density lipoprotein (LDL) cholesterol in certain patients. The FDA also approved a device in July that delivers 420 mg of evolocumab.

So far, sales of evolocumab have fallen short of expectations. The wholesale acquisition cost of more than $14,000 per year is much higher than statins.

In addition, the effect of evolocumab on cardiovascular morbidity and mortality has not been established, although Amgen is currently evaluating the medication in cardiovascular outcomes trials.

“Atherosclerosis is the major underlying cause of cardiovascular disease, which remains the leading cause of death worldwide,” Sean E. Harper, MD, executive vice president of research and development at Amgen, said in a news release. “Now one year after the FDA approved Repatha, nearly two-thirds of patients prescribed Repatha are still being denied access. We are concerned that many patients with uncontrolled LDL cholesterol levels continue to face challenges in accessing a medicine that we now know has a positive impact on plaque burden.”