Cardiovascular Efficacy and Safety of Bococizumab in High-Risk Patients

Effects of Alirocumab on Cardiovascular Events After Coronary Bypass Surgery

BACKGROUND

Patients with acute coronary syndrome (ACS) and history of coronary artery bypass grafting (CABG) are at high risk for recurrent cardiovascular events and death.

OBJECTIVES

This study sought to determine the clinical benefit of adding alirocumab to statins in ACS patients with prior CABG in a pre-specified analysis of ODYSSEY OUTCOMES (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab).

METHODS

Patients (n = 18,924) 1 to 12 months post-ACS with elevated atherogenic lipoprotein levels despite high-intensity statin therapy were randomized to alirocumab or placebo subcutaneously every 2 weeks. Median follow-up was 2.8 years. The primary composite endpoint of major adverse cardiovascular events (MACE) comprised coronary heart disease death, nonfatal myocardial infarction, ischemic stroke, or unstable angina requiring hospitalization. All-cause death was a secondary endpoint. Patients were categorized by CABG status: no CABG (n = 16,896); index CABG after qualifying ACS, but before randomization (n = 1,025); or CABG before the qualifying ACS (n = 1,003).

RESULTS

In each CABG category, hazard ratios (95% confidence intervals) for MACE (no CABG 0.86 [0.78 to 0.95], index CABG 0.85 [0.54 to 1.35], prior CABG 0.77 [0.61 to 0.98]) and death (0.88 [0.75 to 1.03], 0.85 [0.46 to 1.59], 0.67 [0.44 to 1.01], respectively) were consistent with the overall trial results (0.85 [0.78 to 0.93] and 0.85 [0.73 to 0.98], respectively). Absolute risk reductions (95% confidence intervals) differed across CABG categories for MACE (no CABG 1.3% [0.5% to 2.2%], index CABG 0.9% [-2.3% to 4.0%], prior CABG 6.4% [0.9% to 12.0%]) and for death (0.4% [-0.1% to 1.0%], 0.5% [-1.9% to 2.9%], and 3.6% [0.0% to 7.2%]).

CONCLUSIONS

Among patients with recent ACS and elevated atherogenic lipoproteins despite intensive statin therapy, alirocumab was associated with large absolute reductions in MACE and death in those with CABG preceding the ACS event. (ODYSSEY OUTCOMES: Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab; NCT01663402).

The Pleiotropic Effects of Statins - From Coronary Artery Disease and Stroke to Atrial Fibrillation and Ventricular Tachyarrhythmia

Statins, 3-hydroxy-methylglutaryl coenzyme A reductase inhibitors, have been used for decades for the prevention of coronary artery disease and stroke. They act primarily by lowering serum cholesterol through the inhibition of cholesterol synthesis in the liver, which results in the upregulation of low-density lipoprotein receptors in the liver. This results in the removal of low-density lipoproteincholesterol. Studies have suggested that statins may demonstrate additional effects that are independent of their effects on low-density lipoprotein-cholesterol. These have been termed "pleiotropic" effects. Pleiotropic effects may be due to the inhibition of isoprenoid intermediates by statins. Isoprenoid inhibition has effects on the small guanosine triphosphate binding proteins Rac and Rho which in turn effects nicotinamide adenine dinucleotide phosphate oxidases. Therefore, there are changes in endothelial nitric oxide synthase expression, atherosclerotic plaque stability, pro-inflammatory cytokines and reactive oxygen species production, platelet reactivity, and cardiac fibrosis and hypetrophy development. Recently, statins have been compared to the ezetimibe and the recently published outcomes data on the proprotein convertase subtilisin kexin type 9 inhibitors has allowed for a reexamination of statin pleiotropy. As a result of these diverse effects, it has been suggested that statins also have anti-arrhythmic effects. This review focuses on the mechanisms of statin pleiotropy and discusses evidence from the statin clinical trials as well as examining the possible anti-arrhythmic effects atrial fibrillation and ventricular tachyarrhythmias.

Low-density lipoprotein cholesterol lowering treatment: the current approach

In the last 50 years, several clinical and epidemiological studies during have shown that increased levels of low-density lipoprotein cholesterol (LDLc) are associated with the development and progression of atherosclerotic lesions. The discovery of β-Hydroxy β-methylglutaryl-CoA reductase inhibitors (statins), that possess LDLc-lowering effects, lead to a true revolution in the prevention and treatment of cardiovascular diseases. Statins remain the cornerstone of LDLc-lowering therapy. Lipid-lowering drugs, such as ezetimibe and bile acid sequestrants, are prescribed either in combination with statins or in monotherapy (in the setting of statin intolerance or contraindications to statins). Microsomal triglyceride transfer protein inhibitors and protein convertase subtilisin/kexin type 9 (PCSK9) inhibitors are other drug classes which have been investigated for their potential to decrease LDLc. PCSK9 have been approved for the treatment of hypercholesterolemia and for the secondary prevention of cardiovascular events. The present narrative review discusses the latest (2019) guidelines of the European Atherosclerosis Society/European Society of Cardiology for the management of dyslipidemia, focusing on LDLc-lowering drugs that are either already available on the market or under development. We also consider "whom, when and how" do we treat in terms of LDLc reduction in the daily clinical practice.

Comparison of Transatlantic Approaches to Lipid Management: The AHA/ACC/Multisociety Guidelines vs the ESC/EAS Guidelines

The 2018 American Heart Association/American College of Cardiology/Multisociety (AHA/ACC) guidelines and the 2019 European Society of Cardiology/European Atherosclerosis Society (ESC/EAS) guidelines on lipid management were published less than a year apart. Both guidelines focus on reducing cardiovascular risk, but they follow different approaches in terms of methods of risk estimation, definitions of at-risk groups, and treatment goals to achieve this common underlying objective. Both recommend achieving risk-based percentage reductions of low-density lipoprotein cholesterol (LDL-C) levels with statin therapy. The ESC/EAS guidelines additionally recommend target LDL-C levels and are more liberal in supporting the use of both statin and nonstatin therapies across broader patient groups. The AHA/ACC guidelines may be considered more conservative, reserving the addition of nonstatins to maximally tolerated statins for only select patient groups based on specific LDL-C thresholds. One of the main reasons for these differences is incorporation of cost value considerations by the AHA/ACC guidelines, whereas the ESC/EAS guidelines consider an ideal setting with unlimited resources while making recommendations. In this review, we discuss similarities and differences between the 2 lipid guidelines to help clinicians become more cognizant of these recommendations and provide the best individualized patient care.

Stroke Prevention With the PCSK9 (Proprotein Convertase Subtilisin-Kexin Type 9) Inhibitor Evolocumab Added to Statin in High-Risk Patients With Stable Atherosclerosis

Background and Purpose—

The PCSK9 (proprotein convertase subtilisin-kexin type 9) monoclonal antibody evolocumab lowered LDL (low-density lipoprotein) cholesterol by 59% to 0.8 (0.5–1.2) mmol/L and significantly reduced major vascular events in the FOURIER trial (Further Cardiovascular Outcomes Research with PCSK9 Inhibition in Subjects with Elevated Risk). Herein, we report the results of a prespecified analysis of cerebrovascular events in the overall trial population and in patients stratified by prior stroke.

Methods—

FOURIER was a randomized, double-blind trial comparing evolocumab versus placebo in patients with established atherosclerosis, additional risk factors, and LDL cholesterol levels ≥1.8 (or non-HDL [high-density lipoprotein] ≥2.6 mmol/L) on statin therapy. The median follow-up was 2.2 years. We analyzed the efficacy of evolocumab to reduce overall stroke and stroke subtypes, as well as the primary cardiovascular composite end point by subgroups according to a history of stroke.

Results—

Among the 27 564 patients, 469 (1.7%) experienced a total of 503 strokes of which 421 (84%) were ischemic. Prior ischemic stroke, diabetes mellitus, elevated CRP (C-reactive protein), history of heart failure, older age, nonwhite race, peripheral arterial disease, and renal insufficiency were independent predictors of stroke. Evolocumab significantly reduced all stroke (1.5% versus 1.9%; hazard ratio, 0.79 [95% CI, 0.66–0.95]; P =0.01) and ischemic stroke (1.2% versus 1.6%; hazard ratio, 0.75 [95% CI, 0.62–0.92]; P =0.005), with no difference in hemorrhagic stroke (0.21% versus 0.18%; hazard ratio, 1.16 [95% CI, 0.68–1.98]; P =0.59). These findings were consistent across subgroups, including among the 5337 patients (19%) with prior ischemic stroke in whom the hazard ratios (95% CIs) were 0.85 (0.72–1.00) for the cardiovascular composite, 0.90 (0.68–1.19) for all stroke, and 0.92 (0.68–1.25) for ischemic stroke ( P interactions, 0.91, 0.22, and 0.09, respectively, compared with patients without a prior ischemic stroke).

Conclusions—

Inhibition of PCSK9 with evolocumab added to statin in patients with established atherosclerosis reduced ischemic stroke and cardiovascular events in the total population and in key subgroups, including those with prior ischemic stroke.

Registration—

URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01764633.

Clinical profile of patients treated with evolocumab in lipid/internal medicine units of Spain. Observational study (RETOSS-IMU)

OBJECTIVE

To describe the clinical characteristics, the reasons for initiating therapy, and the effects of treatment in the initial phase of evolocumab availability in lipid/internal medicine units in Spain.

METHODS

Retrospective, observational study, based on the medical records of consecutive patients initiating treatment with evolocumab (from February 2016 to July 2017) in 20 internal medicine units in Spain. A review was made of the demographic and clinical characteristics of the patients, the lipid lowering treatment, and the evolution of the lipid profiles between 12weeks pre-initiation and 12±4weeks post-initiation of evolocumab.

RESULTS

A total of 136 patients were analysed, of whom 64.0% were men, and the mean age (standard deviation, SD) was 56.6 (11.5) years. The large majority (75%) had familial hypercholesterolaemia (4 homozygous), and 51.0% of them had suffered at least one cardiovascular event. Atherosclerotic cardiovascular disease (ASCVD) was present in 61% of all patients. At initiation of evolocumab, 61.0% of the patients were taking high-intensity statins, and 60.3% were receiving ezetimibe. The mean (and SD) of LDL-C levels at initiation of evolocumab was 169.1 (56.6) mg/dL. The LDL-C was greater than 160mg/dL in 46.4% of patients, and ≥190mg/dL in 26.5%. During the observation period, evolocumab produced significant reductions in LDL-C of 55.7% (P<.0001), achieving mean values of 74.3mg/dL. At week12, more than half (53.8%) of patients achieved LDL-C levels <70mg/dL, and 26.9% <50mg/dL.

CONCLUSIONS

In the lipid/internal medicine units, evolocumab was mainly prescribed in patients with familial hypercholesterolaemia, with or without ASCVD. The initial use of evolocumab was in accordance with the guidelines of the Spanish Society of Arteriosclerosis (SEA) of 2016, with LDL-C levels being well above the recommended thresholds for treatment initiation. Evolocumab treatment in clinical practice reduced LDL-C levels by about 55%, a similar reduction to that reported in clinical trials. Most patients achieved LDL-C goals.

Statins and PCSK9 inhibitors: A new lipid-lowering therapy

The clinical benefit of lipid-lowering therapies is to reduce circulating levels of atherogenic particles and to ameliorate the risk of atherosclerotic cardiovascular disease (ASCVD). The completion of two major clinical trials on PCSK9 inhibitors (PCSK9i), the FOURIER and the ODYSSEY outcome trials, has marked the beginning of a new era of lipid-lowering drugs. PCSK9i, evolocumab and alirocumab, are monoclonal antibodies that inactivate the liver proprotein convertase subtilisin kexin 9 (PCSK9). Inhibition of PCSK9 increases the number of low-density lipoprotein (LDL) receptors available leading to a profound reduction in circulating LDL particles. By preventing LDL receptor destruction, PCSK9i as adjunct to statin therapy can reduce LDL-C by 50-60% above that achieved by statin therapy alone. In addition, PCSK9i in combination with high-dose statins may reduce cardiovascular events and all-cause mortality in patients with clinical ASCVD. Based on evidence from clinical trials, the 2019 European Society of Cardiology (ESC)/European Atherosclerosis Society (EAS) guidelines for the management of dyslipidemias now include the use of PCSK9i to very high-risk ASCVD patients who are not achieving treatment goals on a maximum tolerated dose of a statin and ezetimibe. However, the cost-effectiveness of PCSK9i therapy is limited to secondary prevention in high-risk patients. This review outlines the main clinical trials leading to a change in the guidelines, clinical practice as well as the future challenges of PCSK9i therapy.

Pharmacokinetics of current and emerging treatments for hypercholesterolemia

Introduction: Reduction of low-density-lipoprotein cholesterol (LDL-C) and other apolipoprotein B (apoB)-containing lipoproteins reduces cardiovascular (CV) events and greater reductions have greater benefits. Current lipid treatments cannot always achieve desirable LDL-C targets and additional or alternative treatments are often needed.Areas covered: In this article, we review the pharmacokinetics of the available and emerging treatments for hypercholesterolemia and focus on recently approved drugs and those at a late stage of development.Expert opinion: Statin pharmacokinetics are well known and appropriate drugs and doses can usually be chosen for individual patients to achieve LDL-C targets and avoid adverse effects and drug-drug interactions. Ezetimibe, icosapent ethyl and the monoclonal antibodies evolocumab and alirocumab have established efficacy and safety. Newer oral agents including pemafibrate and bempedoic acid have generally favorable pharmacokinetics supporting use in a wide range of patients. RNA-based therapies with antisense oligonucleotides are highly specific for their targets and those inhibiting apoB, apoCIII, angiopoietin-like protein 3 and lipoprotein(a) have shown promising results. The small-interfering RNA inclisiran has the notable advantage that a single subcutaneous administration may be effective for up to 6 months. The CV outcome trial results and long term safety data are eagerly awaited for these new agents.

Low LDL Cholesterol by PCSK9 Variation Reduces Cardiovascular Mortality

BACKGROUND

Reduced low-density lipoprotein (LDL) cholesterol due to inhibition of proprotein convertase subtilisin/kexin 9 (PCSK9) reduces cardiovascular events and may therefore also reduce cardiovascular and all-cause mortality.

OBJECTIVES

This study tested the hypothesis that genetically low LDL cholesterol due to PCSK9 variation is causally associated with low cardiovascular and all-cause mortality in the general population.

METHODS

A total of 109,566 individuals from the Copenhagen General Population Study and the Copenhagen City Heart Study were genotyped for PCSK9 R46L (rs11591147), R237W (rs148195424), I474V (rs562556), and E670G (rs505151). During a median follow-up of 10 years (range 0 to 42 years) and 1,247,225 person-years, there were 3,828 cardiovascular deaths and 16,373 deaths from any cause. Results were validated using data on 431,043 individuals from the UK Biobank.

RESULTS

An increasing number of weighted PCSK9 alleles were associated with stepwise lower LDL cholesterol of up to 0.61 mmol/l (24 mg/dl; 18.2%; p for trend <0.001) and with lower cardiovascular mortality (p = 0.001), but not with lower all-cause mortality (p = 0.11). In causal, genetic analyses, a 0.5-mmol/l (19.4-mg/dl) lower LDL cholesterol was associated with risk ratios for cardiovascular and all-cause mortality of 0.79 (95% confidence interval [CI]: 0.63 to 0.99; p = 0.04) and 1.02 (95% CI: 0.94 to 1.12; p = 0.63) in the Copenhagen studies, 0.79 (95% CI: 0.58 to 1.08; p = 0.14) and 0.98 (95% CI: 0.87 to 1.10; p = 0.75) in the UK Biobank, and of 0.79 (95% CI: 0.65 to 0.95; p = 0.01) and 1.01 (95% CI: 0.94 to 1.08; p = 0.85), respectively, in studies combined.

CONCLUSIONS

Genetically low LDL cholesterol due to PCSK9 variation was causally associated with low risk of cardiovascular mortality, but not with low all-cause mortality in the general population.

Residual inflammatory risk after contemporary lipid lowering therapy

BACKGROUND

Recently, there has been an increasing interest in targeting inflammation to reduce major adverse cardiovascular events (MACE) in patients with cardiovascular risk. Statins, PCSK9 inhibitors, and ezetimibe have been shown to reduce MACE owing to reduction in low-density lipoproteins cholesterol (LDL-c). Herein, we investigate whether the intensity of these agents is associated with (i) discernible reduction in inflammation measured by the levels of high-sensitivity C-reactive protein (hsCRP); (ii) reduction in MACE; (iii) if there is an association between the baseline hsCRP and MACE.

METHODS AND RESULTS

Electronic databases were searched for randomized controlled trials (RCTs) that compared statins, ezetimibe, PCSK9 inhibitors with placebos/active controls and reported MACEs and hsCRP (mg/L). Studies were stratified based on baseline hsCRP (<2, 2-3, >3) with subgroup analysis conducted across each stratum. Fourteen RCTs including 133 109 patients randomized into more intensive therapy (MIT) and less intensive therapy were selected. Meta-analysis did not demonstrate any significant differences between use of MIT and hsCRP levels (mean difference, -0.02; CI, -0.06, 0.02; P = 0.31). The MIT significantly reduced the risk of MACE (RR, 0.82; CI, 0.75, 0.91; P < 0.001). The relative risk and absolute risk remained consistent across the strata. However, there was a 0.5% statistically significant absolute risk reduction in all-cause mortality in patients with higher hsCRP (RD, -0.005; CI, -0.009, -0.001; P = 0.01).

CONCLUSION

Overall, LDL-c lowering therapies reduce relative risk of MACEs particularly in patients with higher baseline hsCRP. However, there appears to be a residual inflammatory risk despite the use of contemporary lipid lowering agents.

Efficacy and Safety of PCSK9 Monoclonal Antibodies in Patients at High Cardiovascular Risk: An Updated Systematic Review and Meta-Analysis of 32 Randomized Controlled Trials

INTRODUCTION

Proprotein convertase subtilisin/kexin type 9 (PCSK9) monoclonal antibodies are powerful lipid-lowering drugs which have been shown to improve clinical endpoints in patients with hypercholesterolemia. However, it is not clear how effective PCSK9 monoclonal antibodies are for patients at high cardiovascular risk. Also, whether the effectiveness of PCSK9 monoclonal antibodies varies between different drug types, dosages, race, and indications for PCSK9 monoclonal antibodies remains unclear. Therefore, we used recently published studies to systematically evaluate the efficacy and safety of PCSK9 monoclonal antibodies by analyzing the lipid profiles, adverse events, and clinical endpoints in patients at high cardiovascular risk.

METHODS

Randomized controlled trials (RCTs) comparing PCSK9 monoclonal antibodies with placebos or active drugs in patients at high cardiovascular risk were retrieved from electronic databases from their inception until November 2019. Efficacy and safety outcomes included low-density lipoprotein cholesterol (LDL-C) and other lipid profiles, treatment-emergent adverse events (TEAEs) and adverse events of interests, and clinical endpoints. Subgroup analyses based on drug types, dosing, and race were conducted. Statistical analysis was performed using STATA 15.1 and RevMan 5.0.

RESULTS

Thirty-two RCTs were included in the systematic review, and 25 of them (57,090 individuals) were included in the meta-analysis. PCSK9 monoclonal antibodies significantly improved LDL-C and other lipid profiles (P < 0.05), and no racial differences were found. A recommended dose of 140 mg of evolocumab every 2 weeks was likely to produce a relatively stronger effect than 150 mg of alirocumab every 2 weeks in terms of the absolute change (weighted mean differences (WMD) - 0.36; 95% confidence interval (CI) - 0.71 to - 0.01; P = 0.041) and percent change (WMD - 19.53; 95% CI - 32.02 to - 7.04; P = 0.002) in LDL-C levels. Overall, PCSK9 monoclonal antibodies were safe, except for the significantly increased risk of injection site reactions (relative risks (RR) 1.54; 95% CI 1.38-1.71; P < 0.001). Both alirocumab (RR 0.89; 95% CI 0.83-0.95; P < 0.001) and evolocumab (RR 0.86; 95% CI 0.80-0.92; P < 0.001) were associated with a lower risk of major cardiovascular events (MACEs), especially in secondary preventive patients (alirocumab group: RR 0.88; 95% CI 0.82-0.95; P < 0.001; evolocumab group: RR 0.86; 95% CI 0.80-0.92; P < 0.001). The reduction in MACEs was observed in White but not in Asian subjects. No significant reduction of all-cause mortality was found (RR 0.88; 95% CI 0.72-1.07; P = 0.182).

CONCLUSION

Both alirocumab and evolocumab are well tolerated and can greatly improve lipid profiles for patients at high cardiovascular risk. Both PCSK9 monoclonal antibodies significantly reduce the risk of nonfatal MACEs in patients with previous cardiovascular events, but the effect on all-cause mortality remains uncertain.

PCSK9 Monoclonal Antibodies: An Overview

PCSK9 monoclonal antibodies are novel lipid-lowering therapy that have been extensively studied in patients with hypercholesterolemia either as monotherapy or as an add-on to other LLTs. PCSK9 monoclonal antibodies have significantly reduced the low-density lipoprotein cholesterol (LDL-C) plasma level resulting in a better LDL-C goal attainment. The commercially available PCSK9 monoclonal antibodies, alirocumab and evolocumab, have demonstrated reductions in major adverse cardiovascular events such as myocardial infarction, stroke, unstable angina, and the need for coronary revascularization but not mortality. PCSK9 monoclonal antibodies have demonstrated a favorable safety profile. The most reported side effects are mild injection site with no causal relationship proven between the inhibition of PCSK9 and neurocognitive or glycemic adverse events. In this overview, the efficacy and safety of PCSK9 monoclonal antibodies in the treatment of primary and familial hypercholesterolemia will be discussed.

Study design of Dal-GenE, a pharmacogenetic trial targeting reduction of cardiovascular events with dalcetrapib

The objectives of precision medicine are to better match patient characteristics with the therapeutic intervention to optimize the chances of beneficial actions while reducing the exposure to unneeded adverse drug experiences. In a retrospective genome-wide association study of the overall neutral placebo-controlled dal-Outcomes trial, the effect of the cholesteryl ester transfer protein (CETP) modulator dalcetrapib on the composite of cardiovascular death, myocardial infarction or stroke was found to be influenced by a polymorphism in the adenylate cyclase type 9 (ADCY9) gene. Whereas patients with the AA genotype at position rs1967309 experienced fewer cardiovascular events with dalcetrapib, those with the GG genotype had an increased rate and the heterozygous AG genotype exhibited no difference from placebo. Measurements of cholesterol efflux and C-reactive protein (CRP) offered directionally supportive genotype-specific findings. In a separate, smaller, placebo-controlled trial, regression of ultrasonography-determined carotid intimal-medial thickness was only observed in dalcetrapib-treated patients with the AA genotype. Collectively, these observations led to the hypothesis that the cardiovascular effects of dalcetrapib may be pharmacogenetically determined, with a favorable benefit-risk ratio only for patients with this specific genotype. We describe below the design of dal-GenE, a precision medicine, placebo-controlled clinical outcome trial of dalcetrapib in patients with a recent acute myocardial infarction with the unique feature of selecting only those with the AA genotype at rs1967309 in the ADCY9 gene.

Assessing the Potential Risk of Cross-Reactivity Between Anti-Bococizumab Antibodies and Other Anti-PCSK9 Monoclonal Antibodies

BACKGROUND

Anti-drug antibodies (ADAs) to bococizumab were detected in > 40% of subjects in the SPIRE lipid-lowering trials. The risk of cross-reactivity between anti-bococizumab antibodies and other approved anti-proprotein convertase subtilisin/kexin type-9 (PCSK9) monoclonal antibodies (mAbs) was investigated using a single-assay approach.

METHODS

Bococizumab immunogenicity was assessed in SPIRE-HR, a 52-week study. The highest ADA titer sample from each ADA-positive subject (n = 155) was tested in vitro for cross-reactivity to alirocumab and evolocumab using a novel ADA assay approach. Additional specificity tiers within the bococizumab ADA assay against each drug were validated using recombinant PCSK9 as a surrogate cross-reactive positive control. If the highest ADA titer sample showed cross-reactivity, additional samples from that subject were analyzed. Cross-reactivity was determined by the ability of alirocumab or evolocumab to inhibit the sample signal greater than or equal to the cross-reactivity cut-points.

RESULTS

ADAs were detected in 44.0% (155/352) of bococizumab-treated subjects, and 27.0% also developed neutralizing antibodies (NAbs). Median ADA and NAb titers ranged from 276 to 526 and 8 to 12 over the course of the study, respectively. From 155 ADA-positive subjects tested for cross-reactivity, one (0.6%) subject showed weak cross-reactivity to both alirocumab and evolocumab. This cross-reactivity signal was transient (from Days 337 to 373) and undetectable at the last ADA-positive timepoint (Day 407).

CONCLUSION

A novel, single-assay approach was validated to assess the potential cross-reactivity of anti-bococizumab antibodies to alirocumab and evolocumab. In subjects who developed ADAs to bococizumab, the likelihood of clinically relevant cross-reactivity to marketed anti-PCSK9 mAbs is remote, based on the low frequency of cross-reactivity observed, which was weak in signal inhibition and transient in nature.

CLINICAL TRIAL REGISTRATION

The SPIRE-HR study is registered on ClinicalTrials.gov under the identifier NCT01968954.

Genomics of hypertriglyceridemia

With regard to heritability of phenotypes, the serum triglyceride level is considered to be highly heritable, with approximately 50% of its variability estimated to derive from parents. Thus, approximately 50% could be modifiable via environmental factors, including lifestyle and medications. Lipoproteins are definitive risk factors for atherosclerotic cardiovascular disease (ASCVD); among these, low-density lipoprotein (LDL) particles have been established as a causal factor for the development of ASCVD. Recently, triglyceride-rich lipoproteins have emerged as additional lipoproteins, which should be considered as residual targets for ASCVD risk reduction by LDL-lowering therapies. Compared with LDL particles, triglyceride-rich lipoproteins are significantly increased in the postprandial state, making it difficult to assess their clinical relevance. However, numerous pieces of evidence suggest that fasting and non-fasting triglycerides are associated with ASCVD. In addition, a recent meta-analysis of a Mendelian randomization study suggests that consideration of apolipoprotein B (APOB) might be better than considering LDL and triglyceride-rich lipoproteins separately. In this review, we examine (1) how triglyceride levels are determined by genetics, (2) lessons from extreme cases exhibiting severe hypertriglyceridemia, and (3) why triglycerides are important, by highlighting clinical and genetic evidence of their associations with ASCVD risk.

PCSK9 inhibitors: clinical evidence and implementation

The gene encoding PCSK9 was first identified and linked to the phenotype of familial hypercholesterolaemia approximately 15 years ago. Soon after, studies uncovered the role of PCSK9 in the regulation of LDL-receptor recycling and identified loss-of-function variants of PCSK9 that were associated with low circulating levels of LDL cholesterol (LDL-C) and a reduced risk of coronary artery disease. With amazing rapidity, monoclonal antibodies against PCSK9 were developed and studied in large clinical programmes. These PCSK9 inhibitors lowered plasma LDL-C levels by approximately 60%, even in patients already receiving maximum-dose statin therapy. In the past year, three cardiovascular outcome trials were completed and showed that PCSK9 inhibitors significantly reduce the risk of major vascular events. Reassuringly, this benefit comes with no major offsetting adverse events, such as an excess of myalgias, elevation of hepatic aminotransferases levels in the plasma, incident diabetes mellitus or neurocognitive adverse events. The clinical benefit of PCSK9 inhibitors seen in these trials occurred in the setting of reducing LDL-C levels to unprecedentedly low levels, suggesting that more aggressive LDL-C targets should be adopted. New technologies to inhibit PCSK9 are now being harnessed and might further revolutionize our treatment of dyslipidaemia.

[Monoclonal antibodies in cardiovascular diseases and metabolic disorders today]

The use of monoclonal antibodies in cardiovascular diseases and metabolic disorders is still in its infancy. Recent development of anti-PCSK9 monoclonal antibodies for the treatment of dyslipidemia and of patients in secondary prevention is a breakthrough in the field. Anti- PCSK9 antibodies significantly improved LDL cholesterol reduction in patients with familial hypercholesterolemia. These antibodies have also demonstrated a significant reduction of clinical events in patients with previously established atherosclerotic disease such as myocardial infarction, ischemia stroke or peripheral artery disease. Other targets are under investigation such as inflammatory cells and cytokines to reduce atherosclerosis or myocardial lesions following myocardial infarction.

Transient ischaemic attack after spacing the dose of alirocumab: Is it advisable to reduce the doses of PCSK9 inhibitors with very low LDL-cholesterols?

Inhibitors of the protein PCSK9, available since 2015, are capable of reducing the concentration of low density lipoprotein cholesterol by 40 to 70%, thus reducing the cardiovascular risk. The present case reports an adverse cardiovascular event that appeared when spacing out the administration of lipid-lowering treatment. A discussion will be presented on the importance of maintaining low cholesterol levels in order to achieve a greater benefit, according to the latest published clinical studies.

Dyslipidaemias and Cardiovascular Disease: Focus on the Role of PCSK9 Inhibitors

Genetic, experimental and clinical studies have consistently confirmed that inhibition of Proprotein Convertase Subtilisin/Kexin type 9 (PCSK9) can result in significant lowering of LDL-C and two fully human PCSK9 monoclonal antibodies have received regulatory approval for use in highrisk patients. Co-administration of PCSK9 with statins has resulted in extremely low LDL-C levels with excellent short-term safety profiles. While results from Phase III clinical trials provided significant evidence about the role of PCSK9 inhibitors in reducing cardiovascular event rates, their impact on mortality remains less clear. PCSK9 inhibitor therapy can be considered for high-risk patients who are likely to experience significant cardiovascular risk reduction.

Cholesterol Lowering and Stroke: No Longer Room for Pleiotropic Effects of Statins - Confirmation from PCSK9 Inhibitor Studies

BACKGROUND

The relationship between cholesterol levels and stroke has been much less clear than the relationship between cholesterol levels and coronary heart disease. This is likely mostly due to the inadequate power of older studies and the low intensity of cholesterol-lowering interventions available at the time. Because a reduction in stroke has been, conversely, clearly observed in trials with statins, for long "pleiotropic" effects of such drugs, unrelated to cholesterol lowering, have been invoked. In a previous analysis of all randomized trials of cholesterol-lowering treatments reporting on stroke we had, however, reached the conclusion that any cholesterol lowering is related to a significant reduction of stroke, in a relationship that appeared to exist for both statin and nonstatin cholesterol-lowering interventions. Outcome results of the FOURIER trial with evolocumab, SPIRE-1 and -2 with bococizumab, and ODYSSEY OUTCOMES trial with alirocumab now offer the opportunity of clearly confirming or confuting this concept.

METHODS

We here report on an updated meta-regression of the relationship of total cholesterol changes that occur with various drugs or treatments and changes in the risk of stroke compared with control.

RESULTS

Relative risk (RR) figure found in FOURIER, SPIRE-1/2, and ODYSSEY OUTCOMES (0.79, 0.60, and 0.79) are extremely close to the RRs of 0.79, 0.79, and 0.84, respectively, predicted by our new meta-regression.

CONCLUSIONS

These findings offer definitive proof that the pure total (and low-density lipoprotein) cholesterol lowering, with any available lipid-lowering intervention, reduces stroke risk proportional to the extent of cholesterol reduction, without the need of invoking "pleiotropic" effects of any such treatment.

Promising Anti-atherosclerotic Effect of Berberine: Evidence from In Vitro, In Vivo, and Clinical Studies

Elevated levels of plasma cholesterol, impaired vascular wall, and presence of inflammatory macrophages are important atherogenic risk factors contributing to atherosclerotic plaque formation and progression. The interventions modulating these risk factors have been found to protect against atherosclerosis development and to decrease atherosclerosis-related cardiovascular disorders. Nutritional approaches involving supplements followed by improving dietary habits and lifestyle have become growingly attractive and acceptable methods used to control atherosclerosis risk factors, mainly high levels of plasma cholesterol. There are a large number of studies that show berberine, a plant bioactive compound, could ameliorate atherosclerosis-related risk factors. In the present literature review, we put together this studies and provide integrated evidence that exhibits berberine has the potential atheroprotective effect through reducing increased levels of plasma cholesterol, particularly low-density lipoprotein (LDL) cholesterol (LDL-C) via LDL receptor (LDLR)-dependent and LDL receptor-independent mechanisms, inhibiting migration and inflammatory activity of macrophages, improving the functionality of endothelial cells via anti-oxidant activities, and suppressing proliferation of vascular smooth muscle cells. In conclusion, berberine can exert inhibitory effects on the atherosclerotic plaque development mainly through LDL-lowering activity and suppressing atherogenic functions of mentioned cells. As the second achievement of this review, among the signaling pathways through which berberine regulates intracellular processes, AMP-activated protein kinase (AMPK) has a central and critical role, showing that enhancing activity of AMPK pathway can be considered as a promising therapeutic approach for atherosclerosis treatment.

Intensive LDL cholesterol-lowering treatment beyond current recommendations for the prevention of major vascular events: a systematic review and meta-analysis of randomised trials including 327 037 participants

BACKGROUND

The benefits of LDL cholesterol-lowering treatment for the prevention of atherosclerotic cardiovascular disease are well established. However, the extent to which these effects differ by baseline LDL cholesterol, atherosclerotic cardiovascular disease risk, and the presence of comorbidities remains uncertain.

METHODS

We did a systematic literature search (MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials, from inception up to June 15, 2019) for randomised controlled trials of statins, ezetimibe, and proprotein convertase subtilisin/kexin type 9 inhibitors with at least 1000 patient-years of follow-up. Random-effects meta-analysis and meta-regressions were done to assess for risk of major vascular events (a composite of cardiovascular mortality, non-fatal myocardial infarction, non-fatal ischaemic stroke, or coronary revascularisation) per 1 mmol/L (38·7 mg/dL) reduction in LDL cholesterol concentrations.

FINDINGS

327 037 patients from 52 studies were included in the meta-analysis. Each 1 mmol/L reduction in LDL cholesterol was associated with a 19% relative risk (RR) reduction for major vascular events (RR 0·81 [95% CI 0·78-0·84]; p<0·0001). Similar reductions (per 1 mmol/L reduction in LDL cholesterol) were found in trials with participants with LDL cholesterol 2·60 mmol/L or lower, 2·61-3·40 mmol/L, 3·41-4·10 mmol/L, and more than 4·1 mmol/L (p=0·232 for interaction); and in a subgroup of patients who all had a baseline LDL cholesterol less than 2·07 mmol/L (80 mg/dL; RR 0·83 [95% CI 0·75-0·92]; p=0·001). We found greater RR reductions in patients at lower 10-year atherosclerotic cardiovascular disease risk (change in RR per 10% lower 10-year atherosclerotic cardiovascular disease 0·97 [95% CI 0·95-0·98]; p<0·0001) and in patients at younger age across a mean age of 50-75 years (change in RR per 10 years younger age 0·92 [0·83-0·97]; p=0·015). We found no difference in RR reduction for participants with or without diabetes (p=0·878 for interaction) and chronic kidney disease (p=0·934 for interaction).

INTERPRETATION

For each 1 mmol/L LDL cholesterol lowering, the risk reduction of major vascular events is independent of the starting LDL cholesterol or the presence of diabetes or chronic kidney disease. Patients at lower cardiovascular risk and younger age might have a similar relative reduction in risk with LDL-cholesterol lowering therapies and future studies should investigate the potential benefits of earlier intervention.

FUNDING

None.

PCSK9 Inhibition and Atherosclerosis: Current Therapeutic Option and Prospection

Low-density lipoprotein cholesterol (LDL-C) is a pivotal factor in atherosclerotic cardiovascular disease (ASCVD), the leading cause of worldwide mortality. The limitations of statin therapy require alternative treatment strategies to achieve target LDL-C level. Proprotein convertase subtilisin/kexin type 9 (PCSK9) plays an important role in LDLR recycling, consequently regulating plasma cholesterol levels. Monoclonal antibodies targeting PCSK9 increased expression of LDLRs at the cell surface and therefore decreased circulating LDL-C. PCSK9 inhibitors have shown great efficacy in reducing plasma LDL-C levels, which needs to inject once or twice monthly. Though SPIRE sponsors concern the immunogenicity and terminate trials early, FOURIER and ODYSSER OUTCOME trials improved the efficacy of PCSK9 inhibitors in LDL-C reduction. Inclisiran actually is a small interfering RNA (siRNA) developed to inhibit PCSK9 messenger RNA, leading to reduced concentrations of the PCSK9 protein and thereby lower concentrations of LDL-C. Inclisiran is a latest alternative treatment to cholesterol-lowering therapeutics. Twice injections of inclisiran durably reduced LDL-C levels over 1 year. siRNA therapeutics provided a simple, novel, and less frequent approach to LDL-C reduction in phase I and II trials, which may be used either as in combination with statin therapeutics or a stand-alone therapy in the future.

Lipid-modifying therapy in chronic kidney disease: Pathophysiological and clinical considerations

Chronic kidney disease (CKD), which affects >10% of the population worldwide, is associated with a dramatically increased rate of cardiovascular disease (CVD). More people with CKD will die from CVD than develop end-stage renal disease with dialysis-dependency. However, the contribution of classical atherosclerotic cardiovascular risk factors is less evident than in the general population. Particularly, the relationship between dyslipidemia and CVD morbidity and mortality in CKD patients is not as evident as in the general population. While LDL cholesterol-lowering drugs such as statins significantly reduce the rate of cardiovascular events in the general population, their role in patients with end-stage renal disease has been questioned. This could be caused by a shift from atherosclerotic to non-atherosclerotic CVD in patients with advanced CKD, which cannot be effectively prevented by lipid-lowering drugs. In addition, many lines of evidence suggest that impaired renal function directly affects the metabolism, composition and functionality of lipoproteins, which may affect their responsiveness to pharmacological interventions. In this review, we highlight the challenges for the therapeutic application of lipid-lowering treatment strategies in CKD and discuss why treatment strategies used in the general population cannot be applied uncritically to CKD patients.

Meta-analysis of Randomized Controlled Trials Assessing the Impact of Proprotein Convertase Subtilisin/Kexin Type 9 Antibodies on Mortality and Cardiovascular Outcomes

Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition by monoclonal antibodies has been shown to reduce low density lipoprotein (LDL-C) but its effects on cardiovascular (CV) outcomes have not been fully described. The aim of this study is to assess the impact of PCSK9 inhibition on mortality and CV outcomes by pooling data from all available randomized clinical trials (RCT) of PCSK9 inhibitors. We conducted a comprehensive search of electronic databases, up to December 1, 2018, for all RCTs comparing PCSK9 inhibition to placebo or ezetimibe in patients with hypercholesterolemia or coronary artery disease receiving maximally tolerated statin for primary or secondary prevention of mortality and cardiovascular outcomes. We used random-effects meta-analyses to summarize the studies. We retained 23 RCTs having included 88,041 patients in primary and secondary prevention. The follow-up ranged from 6 to 36 months. PCSK9 inhibition was not significantly associated with reductions in total mortality (odds ratio [OR] 0.91, 95% confidence interval [CI] 078 to 1.06; p = 0.22) and CV mortality (OR 0.95, 95% CI 0.84 to 1.07; p = 0.37). In contrast, PCSK9 inhibition was associated with reductions in myocardial infarction (OR 0.80, 95% CI 0.71 to 0.91; p <0.0001), stroke (OR 0.75, 95% CI 0.65 to 0.85; p <0.0001), and coronary revascularization (OR 0.82, 95% CI 0.77 to 0.88; p <0.0001). In conclusion, PCSK9 inhibition was associated with reductions in myocardial infarction, stroke, and coronary revascularization. Future analyses may identify high-risk patients who may benefit more from these agents and longer follow-up of current or new trials may show a mortality benefit.

Therapeutic effect of nanoliposomal PCSK9 vaccine in a mouse model of atherosclerosis

BACKGROUND

Proprotein convertase subtilisin/kexin 9 (PCSK9) is an important regulator of low-density lipoprotein receptor (LDLR) and plasma levels of LDL cholesterol (LDL-C). PCSK9 inhibition is an efficient therapeutic approach for the treatment of dyslipidemia. We tested the therapeutic effect of a PCSK9 vaccine on dyslipidemia and atherosclerosis.

METHODS

Lipid film hydration method was used to prepare negatively charged nanoliposomes as a vaccine delivery system. An immunogenic peptide called immunogenic fused PCSK9-tetanus (IFPT) was incorporated on the surface of nanoliposomes using DSPE-PEG-maleimide lipid (L-IFPT) and adsorbed to Alhydrogel® (L-IFPTA+). The prepared vaccine formulation (L-IFPTA+) and empty liposomes (negative control) were inoculated four times with bi-weekly intervals in C57BL/6 mice on the background of a severe atherogenic diet and poloxamer 407 (thrice weekly) injection. Antibody titers were evaluated 2 weeks after each vaccination and at the end of the study in vaccinated mice. Effects of anti-PCSK9 vaccination on plasma concentrations of PCSK9 and its interaction with LDLR were determined using ELISA. To evaluate the inflammatory response, interferon-gamma (IFN-γ)- and interleukin (IL)-10-producing splenic cells were assayed using ELISpot analysis.

RESULTS

L-IFPTA+ vaccine induced a high IgG antibody response against PCSK9 peptide in the vaccinated hypercholesterolemic mice. L-IFPTA+-induced antibodies specifically targeted PCSK9 and decreased its plasma consecration by up to 58.5% (- 164.7 ± 9.6 ng/mL, p = 0.0001) compared with the control. PCSK9-LDLR binding assay showed that generated antibodies could inhibit PCSK9-LDLR interaction. The L-IFPTA+ vaccine reduced total cholesterol, LDL-C, and VLDL-C by up to 44.7%, 51.7%, and 19.2%, respectively, after the fourth vaccination booster, compared with the control group at week 8. Long-term studies of vaccinated hypercholesterolemic mice revealed that the L-IFPTA+ vaccine was able to induce a long-lasting humoral immune response against PCSK9 peptide, which was paralleled by a significant decrease of LDL-C by up to 42% over 16 weeks post-prime immunization compared to control. Splenocytes isolated from the vaccinated group showed increased IL-10-producing cells and decreased IFN-γ-producing cells when compared with control and naive mice, suggesting the immune safety of the vaccine.

CONCLUSIONS

L-IFPTA+ vaccine could generate long-lasting, functional, and safe PCSK9-specific antibodies in C57BL/6 mice with severe atherosclerosis, which was accompanied by long-term therapeutic effect against hypercholesterolemia and atherosclerosis.

LDL-cholesterol: The lower the better

The reduction of low density lipoprotein-cholesterol (LDL-chol) has been associated with a decrease in cardiovascular morbidity and mortality. It has been demonstrated that there is no value of LDL-chol below which there ceases to be a preventive benefit with its reduction, and neither has it been observed that there is a higher incidence of secondary effects associated with lower concentrations of LDL-chol. Although there is a wide range of lipid-lowering drugs available, a high percentage of patients do not achieve the desired LDL-chol levels. The high-potency statins reduce the LDL-chol by 15-30%, and can double the percentage of patients that reach their desired level. This combination has shown to be safe and effective in the primary and secondary prevention of cardiovascular disease. Another option is the combination of statins with exchange resins, although this requires a more complex management. The inhibition of PCSK9 protein with monoclonal antibodies reduces the LDL-chol by more than 60%, and is effective in the prevention of cardiovascular disease. However, due to its cost, its use is restricted to patients with ischaemia or familial hypercholesterolaemia that do not achieve the desired levels with conventional drugs. The evidence base as regards the benefit and safety of achieving the desired levels of LDL-chol is very wide and is still increasing. In the next few years, it may be necessary to adjust the intensity of the hypercholesterolaemia treatment to the level of vascular risk of the patients, and to the level of reduction necessary to achieve the therapeutic targets. This will result in a more effective cardiovascular prevention and in a better quality of life, particularly in the large group of patients at higher vascular risk.

Cholesterol-Lowering Agents

Loss-of-function variants in PCSK9 (proprotein convertase subtilisin-kexin type 9) are associated with lower lifetime risk of atherosclerotic cardiovascular disease) events. Confirmation of these genetic observations in large, prospective clinical trials in participants with atherosclerotic cardiovascular disease has provided guidance on risk stratification and enhanced our knowledge on hitherto unresolved and contentious issues concerning the efficacy and safety of markedly lowering LDL-C (low-density lipoprotein cholesterol). PCSK9 has a broad repertoire of molecular effects. Furthermore, clinical trials with PCSK9 inhibitors demonstrate that reductions in atherosclerotic cardiovascular disease events are more effective in patients with recent myocardial infarction, multiple myocardial infarctions, multivessel coronary artery disease, and lower extremity arterial disease. The potent LDL-C lowering efficacy of PCSK9 inhibitors provides the opportunity for more aggressive LDL-lowering strategies in high-risk patients with atherosclerotic cardiovascular disease and supports the notion that there is no lower limit for LDL-C. Aggressive LDL-C lowering with fully human PCSK9 monoclonal antibodies has been associated by a safety profile superior to that of other classes of LDL-lowering agents. These clinical trials provide evidence that LDL lowering with PCSK9 inhibitors is an effective therapy for lowering cardiovascular events in high-risk patients with LDL-C levels ≥70 mg/dL on maximally tolerated oral therapies, including statins and ezetimibe.

Patients With High Genome-Wide Polygenic Risk Scores for Coronary Artery Disease May Receive Greater Clinical Benefit From Alirocumab Treatment in the ODYSSEY OUTCOMES Trial

BACKGROUND

Alirocumab, an antibody that blocks PCSK9 (proprotein convertase subtilisin/kexin type 9), was associated with reduced major adverse cardiovascular events (MACE) and death in the ODYSSEY OUTCOMES trial (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab). In this study, higher baseline levels of low-density lipoprotein cholesterol (LDL-C) predicted greater benefit from alirocumab treatment. Recent studies indicate high polygenic risk scores (PRS) for coronary artery disease (CAD) identify individuals at higher risk who derive increased benefit from statins. We performed post hoc analyses to determine whether high PRS for CAD identifies higher-risk individuals, independent of baseline LDL-C and other known risk factors, who might derive greater benefit from alirocumab treatment.

METHODS

ODYSSEY OUTCOMES was a randomized, double-blind, placebo-controlled trial comparing alirocumab or placebo in 18 924 patients with acute coronary syndrome and elevated atherogenic lipoproteins despite optimized statin treatment. The primary endpoint (MACE) comprised death of CAD, nonfatal myocardial infarction, ischemic stroke, or unstable angina requiring hospitalization. A genome-wide PRS for CAD comprising 6 579 025 genetic variants was evaluated in 11 953 patients with available DNA samples. Analysis of MACE risk was performed in placebo-treated patients, whereas treatment benefit analysis was performed in all patients.

RESULTS

The incidence of MACE in the placebo group was related to PRS for CAD: 17.0% for high PRS patients (>90th percentile) and 11.4% for lower PRS patients (≤90th percentile; P<0.001); this PRS relationship was not explained by baseline LDL-C or other established risk factors. Both the absolute and relative reduction of MACE by alirocumab compared with placebo was greater in high versus low PRS patients. There was an absolute reduction by alirocumab in high versus low PRS groups of 6.0% and 1.5%, respectively, and a relative risk reduction by alirocumab of 37% in the high PRS group (hazard ratio, 0.63 [95% CI, 0.46-0.86]; P=0.004) versus a 13% reduction in the low PRS group (hazard ratio, 0.87 [95% CI, 0.78-0.98]; P=0.022; interaction P=0.04).

CONCLUSIONS

A high PRS for CAD is associated with elevated risk for recurrent MACE after acute coronary syndrome and a larger absolute and relative risk reduction with alirocumab treatment, providing an independent tool for risk stratification and precision medicine.

Targeting the peptidase PCSK9 to reduce cardiovascular risk: Implications for basic science and upcoming challenges

LDL cholesterol (LDL-C) plays a central role in the progression of atherosclerosis. Statin therapy for lowering LDL-C reduces the risk of atherosclerotic cardiovascular disease and is the recommended first-line treatment for patients with high LDL-C levels. However, some patients are unable to achieve an adequate reduction in LDL-C with statins or are statin-intolerant; thus, PCSK9 inhibitors were developed to reduce LDL-C levels, instead of statin therapy. PCSK9 monoclonal antibodies dramatically reduce LDL-C levels and cardiovascular risk, and promising new PCSK9 inhibitors using different mechanisms are currently being developed. The absolute benefit of LDL-C reduction depends on the individual absolute risk and the achieved absolute reduction in LDL-C. Therefore, PCSK9 inhibitors may provide the greatest benefits from further LDL-C reduction for the highest risk patients. Here, we focus on PCSK9-targeted therapies and discuss the challenges of LDL-C reduction for prevention of atherosclerotic cardiovascular disease.

Does low-density lipoprotein cholesterol induce inflammation? If so, does it matter? Current insights and future perspectives for novel therapies

BACKGROUND

Dyslipidemia and inflammation are closely interrelated contributors in the pathogenesis of atherosclerosis. Disorders of lipid metabolism initiate an inflammatory and immune-mediated response in atherosclerosis, while low-density lipoprotein cholesterol (LDL-C) lowering has possible pleiotropic anti-inflammatory effects that extend beyond lipid lowering.

MAIN TEXT

Activation of the immune system/inflammasome destabilizes the plaque, which makes it vulnerable to rupture, resulting in major adverse cardiac events (MACE). The activated immune system potentially accelerates atherosclerosis, and atherosclerosis activates the immune system, creating a vicious circle. LDL-C enhances inflammation, which can be measured through multiple parameters like high-sensitivity C-reactive protein (hsCRP). However, multiple studies have shown that CRP is a marker of residual risk and not, itself, a causal factor. Recently, anti-inflammatory therapy has been shown to decelerate atherosclerosis, resulting in fewer MACE. Nevertheless, an important side effect of anti-inflammatory therapy is the potential for increased infection risk, stressing the importance of only targeting patients with high residual inflammatory risk. Multiple (auto-)inflammatory diseases are potentially related to/influenced by LDL-C through inflammasome activation.

CONCLUSIONS

Research suggests that LDL-C induces inflammation; inflammation is of proven importance in atherosclerotic disease progression; anti-inflammatory therapies yield promise in lowering (cardiovascular) disease risk, especially in selected patients with high (remaining) inflammatory risk; and intriguing new anti-inflammatory developments, for example, in nucleotide-binding leucine-rich repeat-containing pyrine receptor inflammasome targeting, are currently underway, including novel pathway interventions such as immune cell targeting and epigenetic interference. Long-term safety should be carefully monitored for these new strategies and cost-effectiveness carefully evaluated.

Essen Risk Score in Prediction of Myocardial Infarction After Transient Ischemic Attack or Ischemic Stroke Without Prior Coronary Artery Disease

Background and Purpose- More intensive secondary prevention with newer drugs may be cost-effective in patients with coronary artery disease (CAD). Whether some subgroups of patients who had a transient ischemic attack (TIA) or ischemic stroke, but no prior CAD are at similar high risk of myocardial infarction as those with prior CAD remains unclear. We determined whether the Essen score identified a subset of TIA/stroke patients without known prior CAD who, nevertheless, had a high risk of myocardial infarction on current secondary prevention management. Methods- In a population-based cohort (Oxford Vascular Study) of consecutive TIA or ischemic stroke patients recruited from 2002 to 2014, 10-year actuarial risks of myocardial infarction and of recurrent ischemic stroke were determined by face-to-face follow-up in patients with and without prior CAD using Kaplan-Meier analyses. Predictive value of the Essen score was assessed with C statistic. Results- Of 2555 patients with TIA/stroke (13 070 patient-years of follow-up), 10-year risk of myocardial infarction in those without prior CAD (n=2017, 78.9%) ranged from 0.9% (95% CI, 0-1.9) at Essen score ≤1 to 29.8% (95% CI, 7.7-46.6) in those with a score ≥5 (C statistic =0.64 [95% CI, 0.57-0.71]; P<0.001). The score tended to be less predictive (difference: P=0.0460) for the risk of recurrent ischemic stroke (C statistic =0.57 [95% CI, 0.54-0.60]). Compared with patients with prior CAD (n=538, 21.1%), an Essen risk score of ≥4 (n=294, 11.5%) in those without prior CAD identified a subgroup at similar high 10-year risks of myocardial infarction (17.2% [95% CI, 6.9-26.3] versus 16.9% [95% CI, 11.5-22.0]) and of recurrent stroke (40.4% [95% CI, 26.7-51.6] versus 32.4% [95% CI, 25.2-38.8]). Conclusions- The Essen score is a simple clinical score to risk-stratify patients with TIA/stroke without prior CAD and to identify subsets who may be at sufficiently high risk of myocardial infarction and recurrent stroke to justify more intensive treatment or inclusion in trials.

Application of PCSK9 Inhibitors in Practice

PCSK9i (protein convertase subtilisin/kexin type 9 inhibitors) are set to revolutionize the treatment of hypercholesterolemia in the management of atherosclerotic risk, but numerous reports have detailed unprecedented barriers to access for these drugs. To overcome these challenges, our group created a model to facilitate provision of this new therapy for patients who qualify according to Food and Drug Administration criteria. This report details the real-world follow-up experience of PCSK9i use in a large patient cohort structured to ensure rigor in data collection, analysis, and interpretation. The 271 patients approved and actively followed in our PCSK9i clinic between July 2015 and August 2018 represent a 97% approval rate from insurance, with 28% of prescriptions requiring at least one appeal. Over 50% of patients were statin intolerant. On average, there was a median lapse of 15 days between initial visit and insurance approval. PCSK9i therapy was affordable for most patients, with an average monthly out-of-pocket expense of $58.05 (median $0). Only 2.3% of patients were unable to initiate or continue therapy because of cost. Reductions from baseline in LDL (low-density lipoprotein) cholesterol and Lp(a) (lipoprotein [a])were comparable to published reports with median reductions of 60% and 23% at 1 year, respectively. PCSK9i therapy was well-tolerated overall, though 9% of patients reported adverse events, and 5% of patients discontinued due mostly to musculoskeletal and flu-like symptoms. Our practice model demonstrates that PCSK9i therapy can be accessed easily and affordably for the majority of eligible patients, resulting in dramatic improvement in lipid profile results. Moreover, our registry data suggest that results from the prospective clinical trials of PCSK9i on LDL and Lp(a) reduction and on tolerability are applicable to a real-world cohort.

PCSK9 inhibitors and cardiovascular outcomes

Introduction: Dyslipidemia, particularly elevated low-density lipoprotein cholesterol (LDL-C), is a key risk factor for atherosclerotic cardiovascular disease (ASCVD), and lipid-lowering drugs are beneficial for the primary and secondary prevention of cardiovascular (CV) disease. While statins are clear first-line drugs, new drug developments such as proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors have been shown to improve cardiovascular outcomes when added to statins. Evolocumab reduced the risk of cardiovascular events in patients with ASCVD when added to maximally tolerated statin therapy (± ezetimibe), and recent data from the ODYSSEY OUTCOMES trial indicate that alirocumab added to maximally tolerated statin therapy (± other lipid-lowering drugs) reduces the risk of cardiovascular events in patients with a recent acute coronary syndrome. In this article the authors review the available data on the effect of PCSK9 inhibitors on cardiovascular outcomes.Areas covered: This article reviews the available data on the effect of PCSK9 inhibitors on CV outcomes. Relevant papers were identified from a search of PubMed/Medline and the Cochrane Central Register of Controlled Trials (CENTRAL).Expert opinion: The authors conclude that PCSK9 inhibitors provide substantial and durable reductions in LDL-C levels and improve cardiovascular outcomes.

Definitions, adjudication, and reporting of pulmonary embolism-related death in clinical studies: A systematic review

BACKGROUND

Pulmonary embolism (PE)-related death is a component of the primary outcome in many venous thromboembolism (VTE) studies. The absence of a standardized definition for PE-related death hampers study outcome evaluation and between-study comparisons.

OBJECTIVES

To summarize definitions for PE-related death used in recent VTE studies and to assess the PE-related death rate.

PATIENTS/METHODS

A systematic literature search was conducted on 26 April 2018 from 1 January 2014 up to the search date in MEDLINE, Embase, and CENTRAL. Cohort studies and randomized trials in which PE-related death was included in the primary outcome were eligible. Screening of titles, abstracts, and full-text articles, and data extraction were independently performed in duplicate by two authors. Study outcomes included the definition for PE-related death, VTE case-fatality rate, and death due to PE rate. Descriptive statistics were used to analyze the data.

RESULTS

Of the 6807 identified citations, 83 studies were included of which 27% were randomized trials, 31% were prospective, and 42% retrospective cohort studies. Thirty-five studies (42%) had a central adjudication committee. Thirty-eight (46%) reported a definition for PE-related death of which the most frequently used components were "autopsy-confirmed PE" (50%), "objectively confirmed PE before death" (55%), and "unexplained death" (58%). Median VTE case-fatality rate was 1.8% (interquartile range, 0.0-13).

CONCLUSIONS

Only half of the included studies reported definitions for PE-related death, which were very heterogeneous. Case-fatality rate of VTE events varied widely across studies. Standardization of the definition and guidance on adjudication and reporting of PE-related death is needed.

Maximizing the benefits of cholesterol-lowering drugs

PURPOSE OF REVIEW

Drugs to lower LDL-C levels are very widely used. In this brief review, I will use selected recent studies to delineate several important principles that provide a rationale for how to maximize the benefits of using LDL-C lowering drugs to reduce cardiovascular disease. The focus will be on using statins, ezetimibe, and PCSK9 monoclonal antibodies as recent studies have predominantly utilized these agents.

RECENT FINDINGS

The key principles to consider when using LDL-C-lowering drugs to reduce cardiovascular disease are: the lower the LDL-C the better; the sooner and the longer one lowers LDL-C the better; the higher the risk of cardiovascular disease the greater the absolute benefit; the higher the baseline LDL-C the greater the absolute benefit; and compared with the benefits of cholesterol-lowering drugs on reducing cardiovascular disease the risk of side effects is very modest.

SUMMARY

Understanding and employing these key concepts in caring for patients will allow one to use cholesterol-lowering drugs wisely to maximize the reduction of cardiovascular events.