Proprotein Convertase Subtilisin Kexin Research Articles

PCSK9 Induces Tissue Factor Expression by Activation of TLR4/NFkB Signaling.

Proprotein convertase subtilisin kexin 9 (PCSK9) increases LDL cholesterol (C) concentration by accelerating the hepatic degradation of the LDL receptor (R) thus promoting atherogenesis. The molecule, however, also exerts proinflammatory effects independent of circulating LDL-C by enhancing local cytokine production and activation of NFkB, a process that might involve Toll-like receptor 4 (TLR4), a crucial component of the innate immunity system. Tissue factor (TF), a glycoprotein which plays an essential role in coagulation and inflammation, is rapidly induced by circulating monocytes stimulated by proinflammatory agents through NFkB-dependent mechanisms. The aims of our study were (1) to assess whether PCSK9 may induce monocytic TF expression and (2) to evaluate whether the TLR4/NFkB signaling pathway may contribute to that effect. Experiments were carried out in peripheral blood mononuclear cells (PBMCs), THP-1 cells, and HEK293 cells transfected with plasmids encoding the human TLR4 complex. PCSK9 increased procoagulant activity (PCA), mRNA and TF protein expression in both PBMCs and THP-1 cultures. Pre-treatment with inhibitors of TLR4/NFkB signaling such as LPS-RS, CLI-095, and BAY 11-7082, downregulated PCSK9-induced TF expression. A similar effect was obtained by incubating cell cultures with anti-PCSK9 human monoclonal antibody. In TLR4-HEK293 cells, PCSK9 activated the TLR4/NFkB signaling pathway to an extent comparable to LPS, the specific agonist of TLR4s and quantitative confocal microscopy documented the colocalization of PCSK9 and TLR4s. In conclusion, PCSK9 induces TF expression through activation of TLR4/NFkB signaling.

Engineered red blood cells carrying PCSK9 inhibitors persistently lower LDL and prevent obesity.

Low plasma levels of Proprotein Convertase Subtilisin/Kexin 9 (PCSK9) are associated with decreased low-density lipoprotein (LDL) cholesterol and a reduced risk of cardiovascular disease. PCSK9 binds to the epidermal growth factor-like repeat A (EGFA) domain of LDL receptors (LDLR), very low-density lipoprotein receptors (VLDLR), apolipoprotein E receptor 2 (ApoER2), and lipoprotein receptor–related protein 1 (LRP1) and accelerates their degradation, thus acting as a key regulator of lipid metabolism. Antibody and RNAi—based PCSK9 inhibitor treatments lower cholesterol and prevent cardiovascular incidents in patients, but their high-cost hampers market penetration. We sought to develop a safe, long-term and one-time solution to treat hyperlipidemia. We created a cDNA encoding a chimeric protein in which the extracellular N- terminus of red blood cells (RBCs) specific glycophorin A was fused to the LDLR EGFA domain and introduced this gene into mouse bone marrow hematopoietic stem and progenitor cells (HSPCs). Following transplantation into irradiated mice, the animals produced RBCs with the EGFA domain (EGFA-GPA RBCs) displayed on their surface. These animals showed significantly reduced plasma PCSK9 (66.5% decrease) and reduced LDL levels (40% decrease) for as long as 12 months post-transplantation. Furthermore, the EGFA- GPA mice remained lean for life and maintained normal body weight under a high-fat diet. Hematopoietic stem cell gene therapy can generate red blood cells expressing an EGFA—glycophorin A chimeric protein as a practical and long-term strategy for treating chronic hyperlipidemia and obesity.

Lipid Lowering Natural Products Targeting hPCSK9 May Prevent the Severity of COVID-19 Infection

Background: The deadly outbreak of COVID-19 disease caused by novel SARS CoV2 has created an unprecedented global health crisis affecting every sectors of human life and enormous damage to world’s economy. With >16.1 million infections and >650,000 deaths worldwide as of July 27, 2020, there is no treatment for this disease neither is there any available vaccine. Serious research efforts are ongoing on all fronts including treatment, prevention and diagnosis to combat the spread of this infection. A number of targets that include both viral and host proteins have been identified and became part of intense investigation. In this respect the viral surface spike (S) glycoprotein caught the attention most. It is cleaved by multiple host proteases to allow recognition by host receptor human Angiotensin Converting Enzyme2 (hACE2) leading to fusion and viral replication. Natural products, small compounds, antioxidants, peptides, proteins, oligonucleotides, antibodies and other compounds are under investigation for development of antiviral agents against COVID- 19. Objective: Recently cholesterol lowering phytocompounds Quercetin, Swertiamarin and Berberine which promote human Low Density Lipoprotein Receptor (hLDLR) via inhibition of human Proprotein Convertase Subtilisin Kexin9 (hPCSK9) have been shown to block viral infections caused by ebola, influenza, Respiratory Syncytial Virus (RSV), Hepatitis C virus (HCV) and other RNA type viruses. Since SARS CoV2 is a RNA virus with similar genetic structure and infection machinery, it is hypothesised that these phytocompounds may also exhibit antiviral property against COVID-19. Methods: Our above concept is based on recently published studies as well as our herein presented in silico modeling and computational data which suggested strong interactions of hPCSK9 with above phytocompounds and most importantly with hACE2 following its complexation with receptor binding domain (RBD) of SARS CoV2 S protein. Results: These results and a proposed schematic model showing association of hPCSK9 with SARS CoV2 infection are presented in this manuscript. It is proposed that hPCSK9 plays the role of a co-receptor in binding with hACE2:RBD complex and thereby facilitates viral fusion. Conclusion: Our studies suggest that PCSK9 inhibitors may provide beneficial effect against COVID-19 infection by retarding viral fusion through displacement of bound hPCSK9 from its complex with ACE2:RBD of SARS CoV2 S protein.

Clinical Efficacy and Cholesterol-Lowering Effects of Inclisiran

Inclisiran, a drug developed by Novartis, is a recent medication designed to alleviate cardiovascular disease symptoms through improving low-density lipoprotein cholesterol levels. Mechanistically, inclisiran is a chemically synthesized small interfering RNA (siRNA) molecule targeting serine protease proprotein convertase subtilisin-kexin type 9 (PCSK9), resulting in degradation of the LDL receptor. Positive, large-scale clinical trials on the use of inclisiran demonstrate the drug’s efficacy in reducing LDL cholesterol levels in patients afflicted with cardiovascular disease. Moreover, Novartis and the National Health Services (NHS) of the UK have very recently come to an agreement (September 1st, 2021) on the drug’s utility, as the NHS has enabled inclisiran’s use in more than 300,000 patients with a history of cardiovascular disease. However, despite the promising clinical trials on inclisiran as well as its use in the UK, the U.S. Food and Drug Administration (FDA) has yet to approve the drug as a treatment strategy for cardiovascular disease. This review will analyze and discuss the clinical efficacy of inclisiran based on the recent clinical evidence for its pharmacological use in the treatment of cardiovascular diseases. Key words: Inclisiran, efficacy, cholesterol-lowering

Treatment of high- and very high-risk patients for the prevention of cardiovascular events in Europe: baseline demographics from the multinational observational SANTORINI study

Abstract Background The ESC/EAS 2019 guidelines recommend ambitious lower goals for low-density lipoprotein cholesterol (LDL-C), especially for patients with high and very high cardiovascular (CV) risk which could necessitate more intensive lipid-lowering therapy (LLT) regimens. Multiple real-world studies in Europe have demonstrated suboptimal achievement of older 2016 LDL-C goals, with combination therapy with ezetimibe or proprotein convertase subtilisin kexin 9 inhibitors (PCSK9i) used in 9% and 1% of patients, respectively. SANTORINI is the first European observational study since the 2019 guidelines to assess whether management of high- and very high-risk patients has improved. Purpose To describe patient characteristics and treatment patterns of LLT in real-world practice for the management of LDL-C levels in high- and very high-risk patients. Methods Baseline data were assessed from SANTORINI, which recruited patients aged ≥18 years with high and very high CV risk requiring LLT. Risk was defined as per a commonly available assessment system, e.g. the Systematic Coronary Risk Estimation (SCORE) system, for which ESC/EAS guidelines classify high-risk and very high-risk as a calculated 10-year risk of fatal CV disease of ≥5–<10% and ≥10%, respectively. Patients were recruited from 14 European countries across primary and secondary care settings, with patient characteristics, medical history, current LLT and other co-medications documented at baseline. Results Of 9606 patients recruited from March 2020 to February 2021 (55.0% from secondary care), cleaned data on 4308 were available through to February 2021. In this interim report, mean (standard deviation [SD]) age was 64.8 (10.8) years and 27.8% were female. Mean (SD) LDL-C was 2.45 (1.21) mmol/L. The majority of patients were classified as very high risk (69.3%), with 30.6% high risk. ESC/EAS guidelines were the most common basis for risk classification (51.3%), then clinical experience (33.5%) and national guidelines (10.4%). Concomitant CV risk factors included being a current or former smoker (16.5% and 41.8%, respectively), hypertension (70.9%), diabetes (35.4%) and familial hypercholesterolemia (10.1%). At baseline, 18.6% of patients were not receiving any LLT. 54.1% of patients were receiving LLT monotherapy, including 51.1% on statins, 1.4% ezetimibe, 1.2% a PCSK9i, and 0.5% other oral LLT. Combination therapy was used in 27.3% of patients, including 17.1% receiving statin plus ezetimibe, 4.1% PCSK9i plus oral LLT, and 6.1% any other oral combination therapy. Conclusions This large study in patients at high and very high CV risk from 14 European countries suggests that, although the ESC/EAS guidelines are the most frequently used basis for risk classification, LDL-C levels remain substantially higher than recommended goals, with combination therapies underutilised. An expanded data cut from SANTORINI will be reported in 2021. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): Daiichi Sankyo Europe GmbH, Munich, Germany

Efficacy and safety of inclisiran in patients with polyvascular disease: pooled, post hoc analysis of the ORION-9, ORION-10 and ORION-11, phase 3 randomised controlled trials

Abstract Background Approximately 25% of patients (pts) with atherosclerotic cardiovascular disease (ASCVD) have polyvascular disease (PVD), which involves ≥2 coronary, cerebrovascular, and peripheral artery beds. PVD is an independent predictor of major adverse cardiovascular (CV) events (MACE) and death.[1,2] Agents that inhibit proprotein convertase subtilisin-kexin type 9 (PCSK9) resulted in reduced low-density lipoprotein cholesterol (LDL-C) concentration and MACE incidence in pts with PVD.[3,4] Inclisiran is a small interfering RNA (siRNA) agent targeting PCSK9 messenger RNA that provided effective and sustained reduction in LDL-C concentration and was well tolerated.[5] Purpose To describe the effect inclisiran versus placebo (pbo) in pts with and without PVD. Methods This was a post hoc analysis from the ORION-9 (NCT03397121), ORION-10 (NCT03399370) and ORION-11 (NCT03400800) trials. Pts with heterozygous familial hypercholesterolaemia, ASCVD or risk equivalents were randomised 1:1 to receive 300 mg inclisiran sodium (equivalent to 284 mg inclisiran) or pbo at baseline, Day 90, and 6-monthly thereafter. LDL-C percentage change from baseline to Day 510 and corresponding time-averaged change from Day 90 and to Day 540 were evaluated by presence or absence of PVD (intention-to-treat population). Safety was assessed over 540 days (safety population). Results Of 3454 pts, 470 (13.6%) had PVD and 2984 (86.4%) did not. Baseline characteristics were generally balanced between treatment arms in both groups (Table 1). A greater proportion of pts with vs without PVD had CV risk factors at baseline. Mean LDL-C concentration at baseline was lower in pts with vs without PVD (Table 1). Mean (95% CI) pbo-corrected LDL-C percentage change from baseline to Day 510 with inclisiran was −48.9 (−55.6 to −42.2) in pts with PVD and −51.5 (−53.9 to −49.1) in pts without PVD (Table 2). Proportions of pts with treatment-emergent adverse events (TEAE) and treatment-emergent serious adverse events (TESAE) were similar between treatment arms irrespective of PVD status although reported TESAEs were numerically greater in both treatment arms for pts with PVD (Table 2). Clinically relevant TEAEs at the injection site were reported more frequently with inclisiran vs pbo in both groups but all were mild or moderate (Table 2). Proportions of pts with clinically relevant laboratory measurements were low and similar between treatment arms for both groups (Table 2). Conclusions Twice-yearly dosing with inclisiran (after the initial and 3-month doses) provided effective and sustained LDL-C lowering in pts, irrespective of their PVD status, with a safety profile similar to pbo, except for a modest excess of mainly mild TEAEs at the injection site. Notably, TESAEs were reported more frequently in pts with PVD, which was likely due to their more advanced disease. Since pts with PVD are at high risk of CV events, intensive LDL-C lowering may be beneficial to reduce this risk. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): Novartis Pharma AG, Basel, Switzerland

Efficacy and safety of inclisiran in patients with established cerebrovascular disease: pooled, post hoc analysis of the ORION-9, ORION-10 and ORION-11, phase 3 randomised clinical trials

Abstract Background Patients (pts) with hyperlipidaemia and established cerebrovascular disease (CeVD) are at an increased risk of future strokes or other cardiovascular events.[1] In ischaemic stroke survivors, statins and inhibitors of proprotein convertase subtilisin-kexin type 9 (PCSK9) reduce recurrent cardiovascular events including stroke.[2–4] With guidelines increasingly advocating lower LDL-C goals, add-on lipid lowering therapies to statins may be needed. Inclisiran, a first-in-class small interfering RNA (siRNA) targeting PCSK9 messenger RNA, when added to maximally tolerated statin therapy, may provide further LDL-C lowering with a convenient, infrequent dosing schedule in pts with established CeVD. Purpose To assess efficacy and safety of inclisiran in pts with established CeVD. Methods Pts with HeFH, ASCVD or its risk equivalents from ORION-9 (NCT03397121]), ORION-10 (NCT03399370), and ORION-11 (NCT03400800) were randomised 1:1 to receive inclisiran sodium 300 mg (equivalent to 284 mg inclisiran) or placebo (pbo) at Days 1, 90 and 6-monthly thereafter to Day 540. This post hoc analysis included pts with established CeVD (ischaemic stroke, and/or carotid artery stenosis by angiography or ultrasound >70%, and/or prior percutaneous or surgical carotid artery revascularisation). Percentage LDL-C change from baseline to Day 510 and corresponding time-averaged percentage change from baseline after Day 90 to Day 540 were evaluated. Safety was assessed over 540 days. Results Of 202 pts with established CeVD, 110 and 92 received inclisiran and pbo, respectively. At baseline, 90.0% (99/110) of pts in inclisiran and 84.8% (78/92) in pbo group reported prior ischaemic stroke(s); others had carotid artery stenosis and/or carotid revascularisation (Table 1). Mean (95% CI) pbo-corrected LDL-C percentage change from baseline at Day 510 with inclisiran was −55.2% (−64.5 to −45.9); corresponding time-averaged change from baseline after Day 90 to Day 540 was −55.2% (−62.4 to −47.9) (P<0.0001 for each; Table 2). Treatment-emergent adverse event (TEAE) and treatment-emergent serious adverse event (TESAE) were more frequent in the inclisiran vs pbo group but were consistent with the overall pooled (N=3655) population of the combined trials. Clinically relevant TEAEs at the injection site were reported more frequently with inclisiran (3.6% [4/110]) vs pbo (0% [0/92]), but none were severe. Percentage of pts with clinically relevant laboratory measurements was low and similar between treatment groups and consistent with the overall pooled population (Table 2). Conclusions In pts with established CeVD, a twice-yearly dosing with inclisiran (after the initial and 3-month doses) provided sustained additional LDL-C reduction of ∼55%. A modest excess of mild/moderate TEAEs at the injection site were reported with inclisiran. The cardiovascular benefits of inclisiran among patients with established CeVD are being evaluated in ongoing trials. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): Novartis Pharma AG, Basel, Switzerland.

Cardiovascular Event Rates in Statin-Treated Korean Patients with Cardiovascular Disease: Estimates from a Real-World Population Using Electronic Medical Record Data

PurposeTo estimate the risk of recurrent cardiovascular events in a real-world population of very high-risk Korean patients with prior myocardial infarction (MI), ischemic stroke (IS), or symptomatic peripheral artery disease (sPAD), similar to the Further cardiovascular OUtcomes Research with proprotein convertase subtilisin–kexin type 9 Inhibition in subjects with Elevated Risk (FOURIER) trial population.MethodsThis retrospective study used the Asan Medical Center Heart Registry database built on electronic medical records (EMR) from 2000 to 2016. Patients with a history of clinically evident atherosclerotic cardiovascular disease (ASCVD) with multiple risk factors were followed up for 3 years. The primary endpoint was a composite of MI, stroke, hospitalization for unstable angina, coronary revascularization, and all-cause mortality.ResultsAmong 15,820 patients, the 3-year cumulative incidence of the composite primary endpoint was 15.3% and the 3-year incidence rate was 5.7 (95% CI 5.5–5.9) per 100 person-years. At individual endpoints, the rates of deaths, MI, and IS were 0.4 (0.3–0.4), 0.9 (0.8–0.9), and 0.8 (0.7–0.9), respectively. The risk of the primary endpoint did not differ significantly between recipients of different intensities of statin therapy. Low-density lipoprotein cholesterol (LDL-C) goals were only achieved in 24.4% of patients during the first year of follow-up.ConclusionBy analyzing EMR data representing routine practice in Korea, we found that patients with very high-risk ASCVD were at substantial risk of further cardiovascular events in 3 years. Given the observed risk of recurrent events with suboptimal lipid management by statin, additional treatment to control LDL-C might be necessary to reduce the burden of further cardiovascular events for very high-risk ASCVD patients.

Role of PCSK9 in Homocysteine-Accelerated Lipid Accumulation in Macrophages and Atherosclerosis in ApoE-/- Mice.

Background: Homocysteine (Hcy) has been established as an independent risk factor for atherosclerosis, and the involvement of hyperhomocysteinemia (HHcy) in atherosclerotic lesions is complex. Proprotein convertase subtilisin kexin 9 (PCSK9) has vital importance in lipid metabolism, and its inhibitors have intense lipid-lowering and anti-atherosclerotic effects. However, the underlying effect of PCSK9 on HHcy-accelerated dyslipidemia of macrophages is still uncertain. The purpose of this study was to investigate the potential role of PCSK9 in Hcy-induced lipid accumulation and atherosclerotic lesions.Methods: In vitro, gene and protein expressions were assessed by real-time quantitative PCR and western blot in THP-1 macrophages with Hcy incubation. Lipid accumulation and cholesterol efflux were evaluated with Hcy treatment. SBC-115076 was used to examine the role of PCSK9 in ATP-binding cassette transporter A1 and G1 (ABCA1 and ABCG1)-dependent cholesterol efflux. In vivo, lesion area, lipid deposition and collagen contents were determined in aortas of ApoE−/− mice under a methionine diet. SBC-115076 was subcutaneously injected to explore the potential effects of PCSK9 inhibition on alleviating the severity of HHcy-related atherosclerotic lesions.Results: In THP-1 macrophages, Hcy dose- and time-dependently promoted PCSK9 gene and protein levels without regulating the translation of Low-density lipoprotein receptor (LDLR). SBC-115076 used to inhibit PCSK9 largely alleviated lipid accumulation and reversed the cholesterol efflux to apolipoprotein-I(apoA-I) and high-density lipoprotein (HDL) mediated by ABCA1 and ABCG1. In ApoE−/− mice, methionine diet induced HHcy caused larger lesion area and more lipid accumulation in aortic roots. SBC-115076 reduced atherosclerotic severity by reducing the lesion area and lipid accumulation and increasing expressions of ABCA1 and ABCG1 in macrophages from atherosclerotic plaque. In addition, SBC-115076 decreased plasma Hcy level and lipid profiles significantly.Conclusion: PCSK9 promoted lipid accumulation via inhibiting cholesterol efflux mediated by ABCA1 and ABCG1 from macrophages and accelerated atherosclerotic lesions under HHcy treatment. Inhibiting PCSK9 may have anti-atherogenic properties in HHcy-accelerated atherosclerosis.

Intensive lipid-lowering therapy, time to think beyond low-density lipoprotein cholesterol.

Statins have been shown to be effective in reducing cardiovascular events. Their magnitude of benefits has been proportionate to the reduction in low-density lipoprotein cholesterol (LDL-c). Intensive lipid-lowering therapies using ezetimibe and more recently proprotein convertase subtilisin kexin 9 inhibitors have further improved clinical outcomes. Unselective application of these treatments is undesirable and unaffordable and, therefore, has been guided by LDL-c level. Nonetheless, the residual risk in the post-statin era is markedly heterogeneous, including thrombosis and inflammation risks. Moreover, the lipo-protein related risk is increasingly recognised to be related to other non-LDL-c markers such as Lp(a). Emerging data show that intensive lipid-lowering therapy produce larger absolute risk reduction in patients with polyvascular disease, post coronary artery bypass graft and diabetes. Notably, these clinical entities share similar phenotype of large burden of atherosclerotic plaques. Novel plaque imaging may aid decision making by identifying patients with propensity to develop lipid rich plagues at multi-vascular sites. Those patients may be suitable candidates for intensive lipid lowering treatment.

Discovery of Novel Small Molecule Inhibitors Disrupting the PCSK9-LDLR Interaction.

Proprotein convertase subtilisin kexin 9 (PCSK9) has been identified as a reliable therapeutic target for hypercholesterolemia and coronary artery heart diseases since the monoclonal antibodies of PCSK9 have launched. Disrupting the protein-protein interaction (PPI) between PCSK9 and the low-density lipoprotein receptor (LDLR) has been considered as a promising approach for developing PCSK9 inhibitors. However, PPIs have been traditionally considered difficult to target by small molecules since the PPI surface is usually large, flat, featureless, and without a "pocket" or "groove" for ligand binding. The PCSK9-LDLR PPI interface is such a typical case. In this study, a potential binding pocket was generated on the PCSK9-LDLR PPI surface of PCSK9 through induced-fit docking. On the basis of this induced binding pocket, virtual screening, molecular dynamics (MD) simulation, and biological evaluations have been applied for the identification of novel small molecule inhibitors of PCSK9-LDLR PPI. Among the selected compounds, compound 13 exhibited certain PCSK9-LDLR PPI inhibitory activity (IC50: 7.57 ± 1.40 μM). The direct binding affinity between 13 and PCSK9 was determined with a KD value of 2.50 ± 0.73 μM. The LDLR uptake function could be also restored to a certain extent by 13 in HepG2 cells. This well-characterized hit compound will facilitate the further development of novel small molecule inhibitors of PCSK9-LDLR PPI.

The power of lipid registries for cardiovascular disease prevention.

Lipid registry-based research is a valuable tool for assessing current lipid management in patients at risk of cardiovascular disease (CVD). Results of several registries are useful for improving clinical practice highlight gaps between guidelines and their implementation and potential impact on population health. We summarize recent clinical studies based on lipid registries. Current guidelines for lipid management recommend high-intensity statins and concomitant therapies such as ezetimibe and proprotein convertase subtilisin-kexin type 9 inhibitors for high-risk patients. However, recent observational studies show that the majority of patients received inadequate lipid-lowering therapy (LLT), and the low-density lipoprotein-cholesterol (LDL-C) goal attainment rates are still unsatisfactory. There is a clear gap between lipid guidelines and lipid management in clinical practice. Clinical studies based on registry databases represent real-world conditions, as opposed to clinical trials. Contemporary registry data reveal that only half of the patients received high-intensity statins, and less than half achieve the LDL-C <70 mg/dL in secondary prevention. In addition, the major reasons for insufficient therapy have been shown to be not only side effects of LLT, but poor adherence by patients to medication regimens and low use of combination therapies by physicians. The real-world evidence from lipid registries clarifies gaps, areas for focus for implementation, to improve CVD prevention.

Effect of evolocumab on acute arterial events across all vascular territories : results from the FOURIER trial

We assessed the impact of the proprotein convertase subtilisin-kexin type 9 (PCSK9) inhibitor evolocumab on acute arterial events across all vascular territories, including coronary, cerebrovascular, and peripheral vascular beds, in patients with established atherosclerotic cardiovascular disease (ASCVD). In the FOURIER trial, 27 564 patients with stable ASCVD on statin therapy were randomly assigned to evolocumab or placebo. Acute arterial events were a composite of acute coronary (coronary heart disease death, myocardial infarction, or urgent coronary revascularization), cerebrovascular (ischaemic stroke, transient ischaemic attack, or urgent cerebral revascularization), or peripheral vascular (acute limb ischaemia, major amputation, or urgent peripheral revascularization) events. Of the 2210 first acute arterial events, 74% were coronary, 22% were cerebrovascular, and 4% were peripheral vascular. Evolocumab reduced first acute arterial events by 19% (hazard ratio [HR] 0.81 [95% confidence interval 0.74-0.88]; P < 0.001), with significant individual reductions in acute coronary (HR 0.83 [0.75-0.91]), cerebrovascular (HR 0.77 [0.65-0.92]), and peripheral vascular (HR 0.58 [0.38-0.88]) events. There were 3437 total events (first plus recurrent), with evolocumab reducing total events by 24% (incidence rate ratio 0.76 [0.69-0.85]). The magnitude of reduction in acute arterial events with evolocumab numerically increased over time, with a 16% reduction (HR 0.84 [0.75-0.95]) in the first year followed by a 24% reduction (HR 0.76 [0.67-0.85]) thereafter. The addition of the PCSK9 inhibitor evolocumab to statin therapy reduced acute arterial events across all vascular territories with a robust effect over time, indicating a pan-vascular impact of aggressive lipid-lowering therapy on these acute and clinically meaningful events. URL: https://www.clinicaltrials.gov. Unique identifier: NCT01764633.

Lipid-Lowering Drug Therapy: Critical Approach for Implementation in Clinical Practice.

Increased levels of low-density lipoprotein cholesterol (LDL-C) are recognized as a primary risk factor for atherosclerotic cardiovascular disease, which remains the leading cause of death worldwide. Lowering LDL-C levels clearly reduces the risk of cardiovascular events, with benefits related to both absolute reduction and duration of treatment; however, a threshold below which low LDL-C levels can be dangerous has never been established. Since the discovery of statins, cardiovascular research has focused on developing new lipid-lowering agents. Ezetimibe and proprotein convertase subtilisin–kexin type 9 inhibitors have been found to further reduce LDL-C values and subsequent cardiovascular risk. Novel recently approved inclisiran and bempedoic acid, currently being tested in cardiovascular outcomes studies, are further expanding our pharmacological armamentarium, enabling the clinician to diminish residual risk related to LDL-C. Moreover, new agents are paving the way to successful treatment of homozygous familial hypercholesterolemia. This review summarizes the main characteristics of current and emerging lipid-lowering therapies to assist with comprehensive evidence-based decision making.

The LDLR c.501C>A is a disease-causing variant in familial hypercholesterolemia

BackgroundAs an autosomal dominant disorder, familial hypercholesterolemia (FH) is mainly attributed to disease-causing variants in the low-density lipoprotein receptor (LDLR) gene. The aim of this study was to explore the molecular mechanism of LDLR c.501C>A variant in FH and assess the efficacy of proprotein convertase subtilisin kexin type 9 (PCSK9) inhibitor treatment for FH patients.MethodsThe whole-exome sequencing was performed on two families to identify disease-causing variants, which were verified by Sanger sequencing. The function of LDLR variant was further explored in HEK293 cells by Western Blot and confocal microscopy. Besides, the therapeutic effects of PCSK9 inhibitor treatment for two probands were assessed for 3 months.ResultsAll members of the two families with the LDLR c.501C>A variant showed high levels of LDLC. The relationship between the clinical phenotype and LDLR variants was confirmed in the current study. Both in silico and in vitro analyses showed that LDLR c.501C>A variant decreased LDLR expression and LDL uptake. PCSK9 inhibitor treatment lowered the lipid level in proband 1 by 24.91%. However, the treatment was ineffective for proband 2. A follow-up study revealed that the PCSK9 inhibitor treatment had low ability of lipid-lowering effect in the patients.ConclusionsLDLR c.501C>A variant might be pathogenic for FH. The PCSK9 inhibitor therapy is not a highly effective option for treatment of FH patients with LDLR c.501C>A variant.

Global perspective of familial hypercholesterolaemia: a cross-sectional study from the EAS Familial Hypercholesterolaemia Studies Collaboration (FHSC)

The European Atherosclerosis Society Familial Hypercholesterolaemia Studies Collaboration (FHSC) global registry provides a platform for the global surveillance of familial hypercholesterolaemia through harmonisation and pooling of multinational data. In this study, we aimed to characterise the adult population with heterozygous familial hypercholesterolaemia and described how it is detected and managed globally. Using FHSC global registry data, we did a cross-sectional assessment of adults (aged 18 years or older) with a clinical or genetic diagnosis of probable or definite heterozygous familial hypercholesterolaemia at the time they were entered into the registries. Data were assessed overall and by WHO regions, sex, and index versus non-index cases. Of the 61 612 individuals in the registry, 42 167 adults (21 999 [53·6%] women) from 56 countries were included in the study. Of these, 31 798 (75·4%) were diagnosed with the Dutch Lipid Clinic Network criteria, and 35 490 (84·2%) were from the WHO region of Europe. Median age of participants at entry in the registry was 46·2 years (IQR 34·3-58·0); median age at diagnosis of familial hypercholesterolaemia was 44·4 years (32·5-56·5), with 40·2% of participants younger than 40 years when diagnosed. Prevalence of cardiovascular risk factors increased progressively with age and varied by WHO region. Prevalence of coronary disease was 17·4% (2·1% for stroke and 5·2% for peripheral artery disease), increasing with concentrations of untreated LDL cholesterol, and was about two times lower in women than in men. Among patients receiving lipid-lowering medications, 16 803 (81·1%) were receiving statins and 3691 (21·2%) were on combination therapy, with greater use of more potent lipid-lowering medication in men than in women. Median LDL cholesterol was 5·43 mmol/L (IQR 4·32-6·72) among patients not taking lipid-lowering medications and 4·23 mmol/L (3·20-5·66) among those taking them. Among patients taking lipid-lowering medications, 2·7% had LDL cholesterol lower than 1·8 mmol/L; the use of combination therapy, particularly with three drugs and with proprotein convertase subtilisin-kexin type 9 inhibitors, was associated with a higher proportion and greater odds of having LDL cholesterol lower than 1·8 mmol/L. Compared with index cases, patients who were non-index cases were younger, with lower LDL cholesterol and lower prevalence of cardiovascular risk factors and cardiovascular diseases (all p<0·001). Familial hypercholesterolaemia is diagnosed late. Guideline-recommended LDL cholesterol concentrations are infrequently achieved with single-drug therapy. Cardiovascular risk factors and presence of coronary disease were lower among non-index cases, who were diagnosed earlier. Earlier detection and greater use of combination therapies are required to reduce the global burden of familial hypercholesterolaemia. Pfizer, Amgen, Merck Sharp & Dohme, Sanofi-Aventis, Daiichi Sankyo, and Regeneron.

The Effects of Exercise on Lipid Biomarkers.

The World Health Organization has declared obesity to be a global epidemic that increases cardiovascular disease (CVD) mortality risk factors, such as hypertension, diabetes, dyslipidemia, and atherosclerosis. The increasing ratio of time spent in sedentary activities to that spent performing physically demanding tasks increases the trends to obesity and susceptibility to these risk factors. Dyslipidemia is the foundation of atherosclerotic buildup and lipoproteins serve as cofactors to the inflammatory processes that destabilize plaques. Increasing cardiorespiratory fitness and muscular strength helps attenuate concentrations of low-density lipoproteins (LDLs), such as LDL cholesterol, and increase levels of high-density lipoprotein cholesterol, as well as reduce proprotein convertase subtilisin kexin type 9 expression. Effects of physical activity on the inflammatory pathways of atherosclerosis, specifically C-reactive protein, are more closely related to reducing the levels of adiposity in tandem with increasing fitness, than with exercise training alone. The purpose of this review is to describe the physiology of dyslipidemia and relate it to CVD and exercise therapies.

Elevated Lipoprotein(a): Background, Current Insights and Future Potential Therapies.

Lipoprotein(a) forms a subfraction of the lipid profile and is characterized by the addition of apolipprotein(a) (apo(a)) to apoB100 derived particles. Its levels are mostly genetically determined inversely related to the number of protein domain (kringle) repeats in apo(a). In epidemiological studies, it shows consistent association with cardiovascular disease (CVD) and most recently with extent of aortic stenosis. Issues with standardizing the measurement of Lp(a) are being resolved and consensus statements favor its measurement in patients at high risk of, or with family histories of CVD events. Major lipid-lowering therapies such as statin, fibrates, and ezetimibe have little effect on Lp(a) levels. Therapies such as niacin or cholesterol ester transfer protein (CETP) inhibitors lower Lp(a) as well as reducing other lipid-related risk factors but have failed to clearly reduce CVD events. Proprotein convertase subtilisin kexin-9 (PCSK9) inhibitors reduce cholesterol and Lp(a) as well as reducing CVD events. New antisense therapies specifically targeting apo(a) and hence Lp(a) have greater and more specific effects and will help clarify the extent to which intervention in Lp(a) levels will reduce CVD events.

Implications of new clinical practice guidance on familial hypercholesterolaemia for Australian general practitioners.

Familial hypercholesterolaemia (FH) is a monogenic lipid disorder that may be overlooked in the diagnostic process. The aim of this article is to review the key areas for identification and management of FH that affect Australian general practitioners (GPs). Recent consensus advice on the care of patients with FH in Australia provides an opportunity for GPs to increase their awareness and skills in diagnosing and managing FH. New Medicare Benefits Schedule items for genetic testing and Pharmaceutical Benefits Scheme listing for the use of proprotein convertase subtilisin/kexin 9 (PCSK9) inhibitors offer GPs additional supports to improve the care of patients with FH. Ashared-care approach between GPs and non-GP specialists with expertise in multiple disciplines offers the best option to facilitate genetic testing and management of index cases and affected family relatives. Implementation of this guidance in the primary care setting remains an ongoing challenge and needs to be embraced as a high priority.

Association of serum proprotein convertase Subtilisin/Kexin Type 9 (PCSK9) level with thyroid function disorders.

We aimed at demonstrating the effect of thyroid function status on proprotein convertase subtilisin kexin type 9 (PCSK9) and determining the effect of thyroid hormones on lipid metabolism by comparing the PCSK9 levels of patients with subclinical hypothyroidism, overt hypothyroidism, and hyperthyroidism. 124 patients with thyroid disorders, aged between 18 and 65 years, were included in this study. The participants were divided into 3 groups. Group 1 comprised 52 patients with subclinical hypothyroidism, Group 2 comprised 40 patients with overt hypothyroidism, and Group 3 comprised 32 patients with hyperthyroidism. In all of these groups, the thyroid-stimulating hormone (TSH), free triiodothyronine (fT3), free thyroxine (fT4), low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglyceride, total cholesterol, fasting serum glucose, antithyroid peroxidase antibody, antithyroglobulin antibody, and PCSK9 levels were measured. No significant difference was found between the 3 groups in terms of age, gender, and body mass indices. Median PCSK9 measurements were 14.55 ng/mL in Group 1, 14.895 ng/mL in Group 2, and 9.775 ng/mL in Group 3. There was a significant difference in the PCSK9 levels between Group 1-Group 3 and Group 2-Group 3 (p <0.0001 and p <0.0001, respectively). A positive correlation between PCSK9 and the TSH levels (r = 0.211, p= 0.019), and a negative correlation (r = -0,239, p = 0.009 and r = -, 0.218, p = 0.015) between the fT3 and fT4 levels were found. The serum PCSK9 levels were shown to be associated with thyroid dysfunction. However, no relationship was observed between the serum PCSK9 level and thyroid autoantibody positivity, and obesity in this study.