OBJECTIVES : Proprotein convertase subtilisin-kexin type 9 inhibitors (PCSK9-i) are a new class of drugs, lowering low-density lipoprotein cholesterol. Alirocumab and evolocumab were both approved in 2015 by FDA. Efficacy of PCSK9-i has been established based on randomized controlled trials, such as FOURIER trial, which indicated that treatment with evolocumab reduced the risk of cardiovascular events; meanwhile, treatment status in real-world setting is still unclear. We investigated the treatment status using real-world claims data.

METHODS : MarketScan Commercial Database (2013-2017), including about 30 million insureds (mainly <65 years) was used. Patients who had prescription of PCSK9-i (evolocumab or alirocumab) and ≥3 months baseline period before the first prescription were selected. Comorbidities based on ICD-10 code and prescribed drugs by drug class in baseline period were calculated. Among those, who met criteria of patients in FOURIER trial, which were available in the database, were extracted, and examined incidence of myocardial infarction (MI) based on ICD-9/10 code.

RESULTS : There were 6,216 patients prescribed PCSK9-i. Among them, 5,825 patients were selected. Age (average ± SD) in baseline and female ratio were 57.2 ± 7.5 and 40%, respectively. Most frequently observed comorbidities were essential (primary) hypertension (57%), atherosclerotic heart disease of native coronary artery without angina pectoris (52%), and hyperlipidemia, unspecified (51%). Most frequently prescribed drugs were antihyperlipidemic drugs (87%), beta blockers (52%), and antiplatelet agents (33%). Patients who met the criteria of FOURIER trial were 752 (13%). Cumulative incidence rate of MI at 12 months in the patients was 15.5% (CI: 12.5-19.1%), which was higher than primary endpoint including MI and other cardiovascular events in FOURIER trial, 9.9% (<65 years).

CONCLUSIONS : Patients prescribed PCSK9-i are suggested to have high risk for cardiovascular events. Only 13% of patients met criteria of FOURIER trial and showed higher incidence of MI than in the trial.