Alirocumab, a monoclonal antibody that inhibits proprotein convertase subtilisin-kexin type 9 (PCSK9), has been shown to reduce low-density lipoprotein (LDL) cholesterol levels in patients who are ...receiving statin therapy. Larger and longer-term studies are needed to establish safety and efficacy.
We conducted a randomized trial involving 2341 patients at high risk for cardiovascular events who had LDL cholesterol levels of 70 mg per deciliter (1.8 mmol per liter) or more and were receiving treatment with statins at the maximum tolerated dose (the highest dose associated with an acceptable side-effect profile), with or without other lipid-lowering therapy. Patients were randomly assigned in a 2:1 ratio to receive alirocumab (150 mg) or placebo as a 1-ml subcutaneous injection every 2 weeks for 78 weeks. The primary efficacy end point was the percentage change in calculated LDL cholesterol level from baseline to week 24.
At week 24, the difference between the alirocumab and placebo groups in the mean percentage change from baseline in calculated LDL cholesterol level was -62 percentage points (P<0.001); the treatment effect remained consistent over a period of 78 weeks. The alirocumab group, as compared with the placebo group, had higher rates of injection-site reactions (5.9% vs. 4.2%), myalgia (5.4% vs. 2.9%), neurocognitive events (1.2% vs. 0.5%), and ophthalmologic events (2.9% vs. 1.9%). In a post hoc analysis, the rate of major adverse cardiovascular events (death from coronary heart disease, nonfatal myocardial infarction, fatal or nonfatal ischemic stroke, or unstable angina requiring hospitalization) was lower with alirocumab than with placebo (1.7% vs. 3.3%; hazard ratio, 0.52; 95% confidence interval, 0.31 to 0.90; nominal P=0.02).
Over a period of 78 weeks, alirocumab, when added to statin therapy at the maximum tolerated dose, significantly reduced LDL cholesterol levels. In a post hoc analysis, there was evidence of a reduction in the rate of cardiovascular events with alirocumab. (Funded by Sanofi and Regeneron Pharmaceuticals; ODYSSEY LONG TERM ClinicalTrials.gov number, NCT01507831.).
The proprotein convertase subtilisin/kexin type 9 inhibitor alirocumab has been shown to substantially reduce low-density lipoprotein cholesterol (LDL-C). Demonstrating whether efficacy and safety ...are maintained over a long duration of exposure is vital for clinical decision-making. The COMBO II trial compared the efficacy and safety of alirocumab versus ezetimibe over 2 years. A prespecified first analysis was reported at 52 weeks. Here we report the final end-of-study data (on-treatment) and evaluate post hoc the safety profile with longer versus shorter duration of alirocumab exposure. Patients (n = 720) on maximally tolerated statin dose were treated with alirocumab (75/150 mg every 2 weeks) or ezetimibe (10 mg/day). Overall mean adherence for both treatment groups during the first and second year was >97%. At 2 years, LDL-C was reduced by 49% (alirocumab) versus 17% (ezetimibe; p <0.0001), and LDL-C <70 mg/dl was achieved by 73% of alirocumab-treated versus 40% of ezetimibe-treated patients. Overall safety was similar in both treatment groups at 2 years and during the first versus the second year. Local injection-site reactions were reported by 2.5% (alirocumab) versus 0.8% (ezetimibe) during the first year, and 0.2% versus 0.5% during the second year, indicating early occurrence during prolonged alirocumab exposure. Two consecutive calculated LDL-C values <25 mg/dl were observed in 28% of alirocumab-treated patients (vs 0.4% with ezetimibe). Persistent anti-drug antibody responses were observed in 1.3% (6 of 454) of alirocumab-treated versus 0.4% (1 of 231) of ezetimibe-treated patients. Neutralizing antibodies (that inhibit binding in vitro) were observed in 1.5% (7 of 454) of alirocumab-treated patients (0 with ezetimibe), mostly at isolated time points. Alirocumab sustained substantial LDL-C reductions and was well tolerated up to 2 years in the COMBO II trial.
Background
Excess epicardial fat volume (EFV) has been recently implicated in cardiovascular structural and functional abnormalities. It has been associated with abnormal microvascular stiffness (as ...reflected by radial artery waveform; C2), which may result in microvascular dysfunction and contribute to the atypical chest pain syndrome without obstructive coronary artery disease (CAD). Women have been statistically shown to present with atypical chest pain more often than men and specifically without obstructive CAD. The aim of this study is to assess whether excess EFV in female subjects is associated with significant microvascular dysfunction (i.e., C2), in subjects without obstructive CAD.
Results
We screened 596 asymptomatic subjects, ages 20–79, using the Early Cardiovascular Health Risk Scoring System (ECVHRS), which has been reported. Out of the 596 total subjects, 230 subjects had a CACS. Out of these 230 subjects, 77 subjects (45 females; 32 males) had a 0 CACS. The 45 females from this cohort were the subjects of this study, and they were further categorized into 3 groups: group 1 (normal EFV, non-obese female subjects;
n
=16), females with ECVHRS < 3 and ACC/AHA risk score < 5%; group 2 (
n
= 9), females with elevated EFV and no abdominal visceral obesity; and group 3 (
n
=20), females with elevated EFV and abdominal visceral obesity. The average EFV was determined to be 72±20 cm
3
among group 1, which indicates the values for normal EFV. The results in group 2 indicate that excess EFV is contributing to the development of microvascular dysfunction, resulting in abnormal micro-arterial (C2) elasticity (
p
< 0.00001), increase in resting blood pressure (
p
=0.0001), an abnormal rise in blood pressure (BP) at rest and post-mild protocol exercise (PME) (
p
= < 0.00001), and abnormal increase in carotid intima-media thickness (CIMT) (
p
= 0.000164).
Conclusion
Excess EFV appears to be not only a novel cardiovascular risk marker, but also the culprit for other cardiovascular risk markers. Based on these findings, elevated EFV may contribute to the development of the atypical chest pain syndrome in females without obstructive CAD. Additionally, EFV is emerging as a potential clinically relevant significant cardiovascular risk biomarker and may become a target to reduce cardiovascular morbidity and mortality.
PDF
