PCSK9i reduces coronary plaque burden in asymptomatic patients with FH
Alirocumab and Coronary Atherosclerosis in Asymptomatic Patients with Familial Hypercholesterolemia: The ARCHITECT StudyLiterature - Pérez de Isla L, Díaz-Díaz JL, Romero MJ, et al. - Circulation. 2023 Apr 3. doi: 10.1161/CIRCULATIONAHA.122.062557.
Introduction and methods
Patients with FH are at high risk of premature ASCVD, even if they use statins and other lipid-lowering therapies . PCSK9 inhibitors have been shown to reduce the atherosclerotic plaque burden and ASCVD events in patients with previous coronary artery disease . It remains unknown how PCSK9i affect coronary plaque burden in patients with FH.
Aim of the study
The authors investigated the effects of the PCSK9 inhibitor alirocumab on coronary plaque burden and plaque characteristics in asymptomatic patients with FH receiving optimized and stable treatment with maximum tolerated statin dose with or without ezetimibe.
The ARCHITECT study (Effect of Alirocumab on Atherosclerotic Plaque Volume, Architecture and Composition) was a phase IV, open-label, multicenter, single-arm clinical trial. 104 patients (median age 53.3 years, 52% woman) with FH who received optimized and stable treatment with maximum tolerated statin dose with or without ezetimibe were included. Patients were eligible if LDL-c levels <100 mg/dL were not achieved, baseline global coronary plaque burden >30%, and their treating physician prescribed alirocumab. Participants underwent a coronary CTA at baseline, and during follow-up at 78 weeks. During this non-invasive procedure, the entire coronary tree was assessed. Patients received 150 mg of alirocumab subcutaneously every 14 days.
The main end point was the global coronary plaque burden. Secondary end point was the change in coronary plaque characteristics.
- The global coronary plaque burden was decreased at 78 weeks compared to baseline (plaque burden changed from a median of 34.6% (IQR: 32.5 to 36.8) at baseline to 30.4% (IQR: 27.4 to 33.4) at follow-up; P<0.001).
- Coronary plaque burden regression at follow-up occurred in a large portion of patients (87.5%).
- The proportion of calcified and fibrous plaque was increased at follow-up (median change +6.2%; IQR: -0.07 to 14.5; P<0.001; for calcified plaque; and median change +0.3%; IQR:-1.9 to 2.7; P<0.001; for fibrous plaque), whereas the proportion of fibro-fatty and necrotic plaque was decreased (median change -3.9%; IQR: -8.8 to 0.2; P<0.001; for fibro-fatty plaque; and median change -0.6%; IQR: -3.8 to 7.4; P<0.001; for necrotic plaque).
The authors demonstrated that treatment with the PCSK9 inhibitor alirocumab in addition to statin therapy reduced coronary plaque burden and promoted plaque stabilization over a 78 week-study period in asymptomatic patients with FH. The authors highlight that these effects of an PCSK9 inhibitor on atherosclerotic plaques may explain the results obtained with alirocumab in the ODYSSEY OUTCOMES-trial.