PCSK9 inhibitors – past, present and future

Cellular and Molecular Aspects of Managing Familial Hypercholesterolemia: Recent and Emerging Therapeutic Approaches

Familial hypercholesterolemia (FH) as a high-frequency genetic disorder is diagnosed based on family and/or patient's history of coronary heart disease (CHD) or some other atherosclerotic disease, LDL-C levels and/or clinical signs such as tendonous xantomata, arcus cornealis before age 45 years as well as functional mutation in the LDLR, apoB or PCSK9 gene. Its clinical features are detectable since early childhood. Early diagnosis and timely treatment increase life expectancy in most patients with FH. Current FH therapies decrease the level of low-density lipoprotein up to ≥50% from baseline with diet, pharmacotherapeutic treatment, lipid apheresis, and liver transplantation. The cornerstone of medical therapy is the use of more potent statins in higher doses, to which often ezetimibe has to be added, but some FH patients do not achieve the target LDL-C with this therapy Therefore, besides these and the most recent but already established therapeutic approaches including PCSK9 inhibitors, inclisiran, and bempedoic acid, new therapies are on the horizon such as gene therapy, CRISPR/Cas9 strategy etc. This paper focuses on cellular and molecular potential strategies for the treatment of FH.

Association of PCSK9 Variants With the Risk of Atherosclerotic Cardiovascular Disease and Variable Responses to PCSK9 Inhibitor Therapy

Genetic polymorphisms or variations, randomly distributed in a population, may cause drug-gene response variations. Investigation into these polymorphisms may identify novel mechanisms contributing to a specific disease process. Such investigation necessitates the use of Mendelian randomization, an analytical method that uses genetic variants as instrumental variables for modifiable risk factors that affect population health.¹ In the past decade, advances in our understanding of genetic polymorphisms have enabled the identification of genetic variants in candidate genes that impact low-density lipoprotein cholesterol (LDL-C) regulating pathways and cardiovascular disease (CVD) outcomes. A specific candidate gene of interest is that of the LDL receptor degrading protein, PCSK9. In fact, loss-of-function genetic variants for the PCSK9 gene are what first highlighted this pathway as a candidate for pharmacologic inhibition. PCSK9 inhibitors (PCSK9i) are a class of cholesterol-lowering medications that provide significant reductions in LDL by inhibiting the degradation of LDL receptors (LDLR). These inhibitors have also been found to reduce production and enhance clearance of lipoprotein A (Lp[a]), an LDL-like particle currently under study as a separate risk factor for atherosclerotic CVD. Here, we discuss the promise of personalized medicine in developing a more efficacious and individualized pharmacogenomics-based approach for the use of PCSK9i that considers genetic variation and targets different patient populations. This review explores the pharmacogenomics of PCSK9i in the context of PCSK9 allele variants related to drug-metabolizing enzymes and responses since more studies are demonstrating that some patients are hyporesponsive or non-responsive to PCSK9i.² In summary, the pharmacogenomics of PCSK9 are a promising therapeutic target and genetic information from prospective randomized clinical trials is warranted to gain a full understanding of the efficacy and cost-effectiveness of such allele and/or gene-guided PCSK9i therapy.

Associations of serially measured PCSK9, LDLR and MPO with clinical outcomes in heart failure

Aim: To investigate the temporal evolution of plasma proprotein convertase subtilisin/kexin type 9 (PCSK9), low-density lipoprotein receptor (LDLR) and myeloperoxidase (MPO) in relation to clinical outcome in chronic heart failure (CHF). Methodology & results: Trimonthly blood sampling was performed during a median follow-up of 2.2 (IQR 1.4-2.5) years in 263 CHF patients. Seventy patients reached the primary end point (PE) (cardiovascular death, heart transplantation, left ventricular assist device implantation or HF-hospitalization). MPO level was independently associated with the PE; the adjusted (for clinical factors) hazard ratio (aHR) per standard deviation difference in MPO was 1.71 (95% CI: 1.23-2.43) at any time during follow-up. PCSK9 level (HR: 1.45 [1.04-2.06]) and LDLR (HR: 0.66 [0.49-0.87]) were statistical significantly associated with the PE but only in unadjusted analyses. Slope of temporal MPO evolution (aHR: 1.34 [1.12-1.76] per 0.1 standard deviation/year difference in slope) and LDLR (aHR: 0.78 [0.61-0.90]) however, were associated with PE. Conclusion: Temporal patterns of MPO and LDLR are independently associated with clinical outcome in CHF, which illustrates the importance of assessing temporal evolutions. Clinical trial registration information: registered in ClinicalTrials.gov, number NCT01851538. https://clinicaltrials.gov/ct2/show/NCT01851538.

Novel Experimental Agents for the Treatment of Hypercholesterolemia

Atherosclerotic cardiovascular diseases (ASCVD) are still the leading cause of morbidity and mortality in most developed countries and even more in developing countries. Dyslipidemia is a well known main risk factor for ASCVD. Lipid-lowering treatment, particularly lowering LDL-cholesterol (LDL-C), can decrease the risk for ASCVD. New data and guidelines based upon them suggest that we should go with LDL-C levels as low as we can. Therefore, conventional lipid lowering agents (statins and statins+ezetimibe) are not enough mainly because of poor compliance and statin intolerance which is in the real world mostly pseudo-intolerance. PCSK9 inhibitors provided a new hope to further decrease LDL-C but are still expensive, they have to be injected subcutaneously twice a month and their long-lasting adverse effects are not known. Therefore, there is a constant need to develop novel, more potent, more safe, less expensive, more user friendly regimens of hypolipemic agents (bempedoic acid, selective PPAR alpha receptor modulators etc). One of the ways to overcome poor compliance and increase the potency of therapy with less adverse effects are fixed combinations of established drugs (statin+ezetimibe). The future of hypolipemic agents is based on antisense therapy, ie. the use of specific oligonucleotide sequences blocking the translation of the selected protein (targeting apolipoprotein CIII, lipoprotein (a), apolipoprotein B) or RNA silencing technique (PCSK9 mRNA) and are in various stages of clinical trials. Some of them are almost ready to use in everyday clinical practice. High risk and very high risk patients (eg. familial hypercholesterolemia, familial severe chylomicronemia syndrome) will benefit most. The aim of this review is to inform about novel hypolipemic agents – potent and safe drugs for dyslipidemia which should reduce the risk of ASCVD.

An update on PCSK9 inhibitors- pharmacokinetics, drug interactions, and toxicity

INTRODUCTION

While atherosclerotic cardiovascular disease is affecting growing numbers of patients, lipid-lowering therapies have been continuously improving to achieve prevention of cardiovascular events. Thus, the appearance of a novel therapeutic class, PCSK9 inhibitors, has raised both high expectations as well as concern over possible adverse effects.

AREAS COVERED

This current review aims to analyze adverse events of special interest linked to PCSK9 inhibitors and give recommendations regarding further conduct when dealing with patients on this therapy. The most stringent adverse effect, neurocognitive impairment has been investigated in several studies, concluding that PCSK9 inhibitors neither improved nor worsened cognitive function. While new onset diabetes mellitus has also been a cause of concern due to its possible association with lipid lowering therapies, studies conducted so far have dispelled this possibility by showing that PCSK9 inhibitors do not increase this risk. Also, statin-associated muscle symptoms have not been proven to arise after the use of PCSK9 inhibitors, even in statin-intolerant patients.

EXPERT OPINION

In conclusion, it can be safely stated that so far, no compelling evidence links PCSK9 inhibitors to these adverse events; however, long-term trials are always welcome to further assess potential adverse effects.

New Perspectives on Atherogenic Dyslipidaemia and Cardiovascular Disease

Over the past few decades, atherogenic dyslipidaemia has become one of the most common phenotypic presentations of lipid abnormalities, being strongly and unequivocally associated with an increased risk of cardiovascular (CV) disease. Despite the excellent results achieved from statin and non-statin management of LDL cholesterol and CV events prevention, there still remains a significant residual risk, associated with the prevalence of non-LDL cholesterol lipid patterns characterised by elevated triglyceride levels, low HDL cholesterol, a preponderance of small and dense LDL particles, accumulation of remnant lipoproteins and postprandial hyperlipidaemia. These qualitative and quantitative lipid modifications are largely associated with insulin resistance, type 2 diabetes and obesity, the prevalence of which has grown to epidemic proportions throughout the world. In this review, we analyse the pathophysiology of this particular dyslipidaemia, its relationship with the development of atherosclerotic CV disease and, finally, briefly describe the therapeutic approaches, including changes in lifestyle and current pharmacological interventions to manage these lipid alterations aimed at preventing CV events.

Are anti-inflammatory agents and nutraceuticals - novel inhibitors of PCSK9?

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a protease which increases the lysosomal degradation of low density lipoprotein receptor (LDLR) resulting in elevated serum LDL-cholesterol levels. Elevated LDL-cholesterol is the main risk factor for cardiovascular disease (CVD). Antibodies to PCSK9 decrease LDL-cholesterol. Recent studies have suggested a direct relationship between PCSK9 and inflammation and the potential inhibitory effects of anti-inflammatory agents against this enzyme. Nutraceuticals are natural compounds, which have numerous anti-inflammatory and lipid-lowering effects. In this review we focus on anti-inflammatory substances and nutraceuticals, which are beneficial in treatment of dyslipidemia. We also reviewed the recent findings concerning the role of PCSK9 as the main target for molecular mechanisms of these substances.

Association of Serum PCSK9 Levels with Antibiotic Resistance and Severity of Disease in Patients with Bacterial Infections Admitted to Intensive Care Units

BACKGROUND

The results of several studies have suggested that infections and sepsis, either bacterial or viral, might be associated with elevated plasma proprotein convertase subtilisin/kexin type 9 (PCSK9) levels. Since there are no data on PCSK9 levels and antibiotic resistance or the severity of disease in patients with bacterial infections in intensive care units, the aim of this study was to investigate whether any such associations exist.

METHODS

100 patients (46 males, mean age 67.12 ± 1.34 years) with bacterial infections who were staying in an intensive care unit (ICU) longer than 48 h but less than 7 days and who were not receiving corticosteroids were analyzed. Their serum levels of albumin, C-reactive protein, glucose, lactate, blood urea nitrogen, prothrombin (international normalized ratio), total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, serum glutamic oxaloacetic transaminase, serum glutamic pyruvic transaminase, PCSK9, and procalcitonin were measured. The severity of the patients' condition was assessed by using the Glasgow Coma Scale (GCS), the Sequential Organ Failure Assessment (SOFA), and the Acute Physiology and Chronic Health Evaluation II (APACHE II) scales.

RESULTS

Using a hierarchical regression modeling approach, no significant association was found between PCSK9 levels and either the severity of disease (APACHE II, SOFA, and GCS) indices or resistance to antibiotics.

CONCLUSION

The results suggest that there is no association between PCSK9 levels and resistance to antibiotics or the condition of patients hospitalized in intensive care units.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS AND AMERICAN COLLEGE OF ENDOCRINOLOGY GUIDELINES FOR MANAGEMENT OF DYSLIPIDEMIA AND PREVENTION OF CARDIOVASCULAR DISEASE

OBJECTIVE

The development of these guidelines is mandated by the American Association of Clinical Endocrinologists (AACE) Board of Directors and American College of Endocrinology (ACE) Board of Trustees and adheres with published AACE protocols for the standardized production of clinical practice guidelines (CPGs).

METHODS

Recommendations are based on diligent reviews of the clinical evidence with transparent incorporation of subjective factors, according to established AACE/ACE guidelines for guidelines protocols.

RESULTS

The Executive Summary of this document contains 87 recommendations of which 45 are Grade A (51.7%), 18 are Grade B (20.7%), 15 are Grade C (17.2%), and 9 (10.3%) are Grade D. These detailed, evidence-based recommendations allow for nuance-based clinical decision-making that addresses multiple aspects of real-world medical care. The evidence base presented in the subsequent Appendix provides relevant supporting information for Executive Summary Recommendations. This update contains 695 citations of which 203 (29.2 %) are EL 1 (strong), 137 (19.7%) are EL 2 (intermediate), 119 (17.1%) are EL 3 (weak), and 236 (34.0%) are EL 4 (no clinical evidence).

CONCLUSION

This CPG is a practical tool that endocrinologists, other health care professionals, health-related organizations, and regulatory bodies can use to reduce the risks and consequences of dyslipidemia. It provides guidance on screening, risk assessment, and treatment recommendations for a range of individuals with various lipid disorders. The recommendations emphasize the importance of treating low-density lipoprotein cholesterol (LDL-C) in some individuals to lower goals than previously endorsed and support the measurement of coronary artery calcium scores and inflammatory markers to help stratify risk. Special consideration is given to individuals with diabetes, familial hypercholesterolemia, women, and youth with dyslipidemia. Both clinical and cost-effectiveness data are provided to support treatment decisions.

ABBREVIATIONS

4S = Scandinavian Simvastatin Survival Study A1C = glycated hemoglobin AACE = American Association of Clinical Endocrinologists AAP = American Academy of Pediatrics ACC = American College of Cardiology ACE = American College of Endocrinology ACS = acute coronary syndrome ADMIT = Arterial Disease Multiple Intervention Trial ADVENT = Assessment of Diabetes Control and Evaluation of the Efficacy of Niaspan Trial AFCAPS/TexCAPS = Air Force/Texas Coronary Atherosclerosis Prevention Study AHA = American Heart Association AHRQ = Agency for Healthcare Research and Quality AIM-HIGH = Atherothrombosis Intervention in Metabolic Syndrome With Low HDL/High Triglycerides trial ASCVD = atherosclerotic cardiovascular disease ATP = Adult Treatment Panel apo = apolipoprotein BEL = best evidence level BIP = Bezafibrate Infarction Prevention trial BMI = body mass index CABG = coronary artery bypass graft CAC = coronary artery calcification CARDS = Collaborative Atorvastatin Diabetes Study CDP = Coronary Drug Project trial CI = confidence interval CIMT = carotid intimal media thickness CKD = chronic kidney disease CPG(s) = clinical practice guideline(s) CRP = C-reactive protein CTT = Cholesterol Treatment Trialists CV = cerebrovascular CVA = cerebrovascular accident EL = evidence level FH = familial hypercholesterolemia FIELD = Secondary Endpoints from the Fenofibrate Intervention and Event Lowering in Diabetes trial FOURIER = Further Cardiovascular Outcomes Research with PCSK9 Inhibition in Subjects With Elevated Risk trial HATS = HDL-Atherosclerosis Treatment Study HDL-C = high-density lipoprotein cholesterol HeFH = heterozygous familial hypercholesterolemia HHS = Helsinki Heart Study HIV = human immunodeficiency virus HoFH = homozygous familial hypercholesterolemia HPS = Heart Protection Study HPS2-THRIVE = Treatment of HDL to Reduce the Incidence of Vascular Events trial HR = hazard ratio HRT = hormone replacement therapy hsCRP = high-sensitivity CRP IMPROVE-IT = Improved Reduction of Outcomes: Vytorin Efficacy International Trial IRAS = Insulin Resistance Atherosclerosis Study JUPITER = Justification for the Use of Statins in Primary Prevention: An Intervention Trial Evaluating Rosuvastatin LDL-C = low-density lipoprotein cholesterol Lp-PLA2 = lipoprotein-associated phospholipase A2 MACE = major cardiovascular events MESA = Multi-Ethnic Study of Atherosclerosis MetS = metabolic syndrome MI = myocardial infarction MRFIT = Multiple Risk Factor Intervention Trial NCEP = National Cholesterol Education Program NHLBI = National Heart, Lung, and Blood Institute PCOS = polycystic ovary syndrome PCSK9 = proprotein convertase subtilisin/kexin type 9 Post CABG = Post Coronary Artery Bypass Graft trial PROSPER = Prospective Study of Pravastatin in the Elderly at Risk trial QALY = quality-adjusted life-year ROC = receiver-operator characteristic SOC = standard of care SHARP = Study of Heart and Renal Protection T1DM = type 1 diabetes mellitus T2DM = type 2 diabetes mellitus TG = triglycerides TNT = Treating to New Targets trial VA-HIT = Veterans Affairs High-Density Lipoprotein Cholesterol Intervention Trial VLDL-C = very low-density lipoprotein cholesterol WHI = Women's Health Initiative.

Cardiovascular events with PCSK9 inhibitors: an updated meta-analysis of randomised controlled trials

The therapy with proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors efficiently reduces plasma cholesterol levels, which has been recently associated with improvement in cardiovascular outcomes. This meta-analysis aimed at investigating the safety and efficacy of treatment with the clinically available anti-PCSK9 monoclonal antibodies (mAbs) in all published randomized clinical trials (RCTs), updating the available results with the recently published ODYSSEY OUTCOMES trial. Data search was carried out using PubMed/MEDLINE and EMBASE (inception - January 2019). Inclusion criteria were: (1) phase 2 or 3 RCTs; (2) comparing anti-PCSK9 mAbs (specifically evolocumab and alirocumab) with placebo; (3) with effects on outcomes reported; (4) with treatment duration longer than 8 weeks. Odds ratios (ORs) with 95% CIs were used as summary statistics. We pooled the estimates by using both the DerSimonian & Laird method (random-effects model). Between-study heterogeneity was tested by Cochrane's Q test and measured with the I2 statistics. Twenty-eight RCTs comprising 62,281 participants (33,204 in the mAb arm, 29,077 in the placebo arm) were included in the meta-analysis. The treatment follow-up ranged from 8 weeks up to 208 weeks. Overall, no significant difference in all-cause mortality was observed between the two groups (OR 0.93 [95% CI, 0.85-1.03]). The treatment with an anti-PCSK9 mAb was associated with a significant reduction of CV events compared with placebo (OR 0.83 [95% CI, 0.78-0.87]), being the FOURIER and ODYSSEY OUTCOMES studies the major contributors. Both myocardial infarction and stroke were significantly reduced following the treatment with an anti-PCSK9 mAb. No significant difference was observed in cardiovascular mortality (OR 0.94 [95% CI, 0.83-1.07]). The incidence of serious adverse events was similar in the two groups (OR: 0.95, [95% CI, 0.91-0.99]). Thus, the pharmacological approach with anti-PCSK9 mAbs significantly and safely improves cardiovascular outcomes. Despite that, the pooled analysis failed to show a significant cardiovascular mortality benefit with anti-PCSK9 mAb treatment, suggesting that specific longer-term studies are warranted to address this issue. We suggest that the observed delay between the rapid effect on plasma cholesterol levels and the emergence of the clinical benefit, observed both in FOURIER and ODYSSEY OUTCOMES trials, might explain this finding.

Emerging drugs for the treatment of hypercholesterolemia

INTRODUCTION

Despite the consolidated role of statins and ezetimibe to treat hypercholesterolemia, often the desirable low-density lipoprotein cholesterol (LDL-C) values are not achieved, with a consequent increase of the residual cardiovascular (CV) risk. Areas covered: In this review, we summarize the main pharmacological characteristics of new lipid-lowering drugs, such as proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, cholesteryl ester transfer protein inhibitors, microsomal triglyceride transfer protein inhibitors, ATP citrate lyase inhibitors, antisense oligonucleotides, small interfering RNA, and peroxisome proliferator-activated receptors type α agonists. The available clinical evidence of efficacy and safety as well as the prospects of application, based on the different mechanisms and targets of action, is critically discussed. Expert opinion: Some of these emerging agents represent an excellent therapeutic strategy to treat patients with LDL largely out of target, resistant or intolerant to statins, trying to minimize the residual CV risk, modulating different classes of lipoproteins, not just LDL. The main challenge for the large use of emerging drugs is their cost. Thus, the correct identification of the adequate target population for treatment is a priority. This is particularly true for safe, powerful, and fully developed drugs such as the PCSK9 inhibitors, for which a relatively large use is potentially expected.

Can Lp(a) Lowering Against Background Statin Therapy Really Reduce Cardiovascular Risk?

PURPOSE OF REVIEW

The association between elevated plasma levels of lipoprotein (a) [Lp(a)] and atherosclerotic cardiovascular disease (ASCVD) has been discussed for many years. Recent genetic findings have confirmed that elevated Lp(a) similar to elevated LDL-cholesterol (LDL-C) might be causally related to premature ASCVD. Lp(a) is relatively refractory to lifestyle interventions. The results of studies with statins and their possible effect on Lp(a) are conflicting. Specific Lp(a) apheresis is used as a treatment against background statin therapy and can decrease Lp(a). The purpose of this review is to discuss whether new drugs which decrease Lp(a) can prevent ASCVD and decrease ASCVD mortality when applied in addition to statins.

RECENT FINDINGS

Some new LDL-C-lowering drugs such as mipomersen and lomitapide decrease elevated Lp(a) in addition to statins but they have some unpleasant adverse effects. Recently, an antisense oligonucleotide against apo(a), AKCEA-APO(a)Rx, has been shown to selectively decrease Lp(a). The most recent advance in LDL-C lowering are PCSK9 inhibitors. Alirocumab and evolocumab do not only significantly reduce LDL-C on top of maximally tolerated statin therapy and prevent ASCVD events, but also further decrease Lp(a). There is no data to indicate whether mipomersen, lomitapide, or IONIS-APO(a)-LRx decrease ASCVD events and mortality. Conclusive evidence is still lacking as to whether the treatment with PCSK9 inhibitors against background statin therapy actually additionally reduces ASCVD risk due to the lowering of Lp(a) or simply due to lowering LDL-C to levels much lower than high-intensity statin treatment as monotherapy. Ongoing trials will probably provide an answer to these questions.

Comparative efficacy and safety of lipid-lowering agents in patients with hypercholesterolemia: A frequentist network meta-analysis

BACKGROUND

The comparative efficacy and safety of PCSK9 inhibitors, statins, and ezetimibe to lower lipid levels in patients with hypercholesterolemia remain unknown. We aimed to investigate the benefits and harms of the lipid-lowering agents in these patients.

METHODS

PubMed, Embase, and the Cochrane Library were searched from January 1, 2000 to June 1, 2018 for relevant randomized controlled trials (RCTs). Frequentist network meta-analysis was used to pool all estimates. Ranking probabilities were used to rank the comparative effects of all drugs against placebo.

RESULTS

Eighty-four RCTs enrolled 246,706 patients were included. Most of the included were assessed as low risk of bias. The probabilities of PCSK9 inhibitors that ranked first in improving lipid outcomes were all 100%. The probability of statins that ranked first in reducing the risk of cardiovascular (CV) events was 60.6%, and the probability of PCSK9 inhibitor was 37.1%, while no significant difference of efficacy in reducing CV events was observed between the 2 agents (odds ratios [OR] 0.98, 95% CI 0.87-1.11). Statin ranked first in reducing all-cause and CV death. Compared with placebo, statins were associated with reduced risks of all-cause (OR 0.90, 95% CI 0.85-0.96) and CV death (OR 0.83, 95% CI 0.75-0.91) while PCSK9 inhibitors and ezetimibe were not. No agents caused adverse events (including neurocognitive events), except that statins therapy significantly increases the levels of alanine aminotransferase (ALT) (OR 1.89, 95% CI 1.42-2.51) and creatine kinase (CK) (OR 1.45, 95% CI 1.09-1.93) and the incidence of diabetes (OR 1.13, 95% CI 1.02-1.26).

CONCLUSIONS

PCSK9 inhibitors were the most effective lipid-lowering agents in improving lipid levels. Furthermore, PCSK9 inhibitors achieved similar CV benefits like statins, while PCSK9 inhibitors were not associated with any increased risk of statin-related side-effects. Thus, PCSK9 inhibitors may also be recommended as promisingly first-line lipid-lowering treatment for patients with hypercholesterolemia, especially for these with statins intolerance or resistance.

Reduced incidence of cardiovascular events in hyper-Lp(a) patients on lipoprotein apheresis. The G.I.L.A. (Gruppo Interdisciplinare Aferesi Lipoproteica) pilot study

BACKGROUND

Lipoprotein apheresis (LA) is the elective therapy for homozygous and other forms of Familial Hypercholesterolemia, Familial Combined Hypercholesterolemia, resistant/intolerant to lipid lowering drugs, and hyper-lipoproteinemia(a). Lipoprotein(a) [Lp(a)] has been classified as the most prevalent genetic risk factor for coronary artery disease and aortic valve stenosis.

AIM

Our multicenter retrospective study has the aim to analyze the incidence of adverse cardiovascular events (ACVE) before and during the LA treatment, in subjects with elevated level of Lp(a) (>60 mg/dL) [hyper-Lp(a)] and chronic ischemic heart disease.

METHODS

We collected data of 23 patients (mean age 63 ± 9 years, male 77%; from hospital of Pisa 11/23, Pistoia 7/23, Verona 2/23, Padova 2/23 and Ferrara 1/23), with hyper-Lp(a), pre-apheresis LDL-cholesterol <100 mg/dL, cardiovascular disease, on maximally tolerated lipid lowering therapy and LA treatment (median 7 years, interquartile range 3-9 years). The LA treatment was performed by heparin-induced LDL precipitation apheresis (16/23), dextran-sulphate (4/23), cascade filtration (2/23) and immunoadsorption (1/23). The time lapse between first cardiovascular event and beginning of apheresis was 6 years (interquartile range 1-12 years).

RESULTS

The recorded ACVE, before and after the LA treatment inception, were 40 and 10 respectively (p < 0.05), notably, the AVCE rates/year were 0.43 and 0.11 respectively (p < 0.05) with a 74% reduction of event occurrence.

CONCLUSIONS

Our data confirm long-term efficacy and positive impact of LA on morbidity in patients with hyper-Lp(a) and chronic ischemic heart disease on maximally tolerated lipid lowering therapy.

Monascus purpureus for statin and ezetimibe intolerant heterozygous familial hypercholesterolaemia patients: A clinical study

BACKGROUND

Hypercholesterolaemia is a major risk factor for cardiovascular disease and requires effective therapy in affected patients. Statins, the mainstay of lipid-lowering therapy, can cause side effects, including myalgia, in some patients. Ezetimibe, is frequently used as an add-on therapy for statins, and is also used as a monotherapy in statin-intolerant patients, however elevations in liver transaminases can occur. We examined the lipid-lowering efficacy of the natural fungal product Monascus purpureus (MP), which contains the natural statin monacolin K.

METHODS

Fifty-five patients with familial hypercholesterolaemia who had discontinued statins due to muscle symptoms. Patients were placed on a lipid-lowering diet cholesterol-lowering diet (1500-1800 kcal daily, 30% lipids, 19% proteins and 52% carbohydrates). MP was added to the diet at a dose of 300 mg (providing monacolin K 10 mg). Patients were followed for 12 months. Lipid profiles and adverse event data were collected in the normal course of patient care.

RESULTS

After 6 months of treatment with MP and diet therapy, statistically significant changes in low-density lipoprotein cholesterol were evident (-17% for males, -16% for females; p < 0.005) Levels fell to -24% and -27% respectively at 12 months. No patients experienced elevated serum aminotransferases or C-reactive protein levels.

CONCLUSIONS

MP is a viable option for lipid-lowering therapy in statin-intolerant patients with hypercholesterolaemia, with good efficacy and safety profiles.

Evolving targets for the treatment of atherosclerosis

Atherosclerosis is a progressive disease of large arteries and a leading cause of cardiovascular diseases and stroke. Chronic inflammation, aberrant immune response, and disturbances to key enzymes involved with lipid metabolism are characteristic features of atherosclerosis. Apart from targeting the derangements in lipid metabolism, therapeutic modulation to regulate chronic inflammation and the immune system response may prove to be very promising strategies in the management of atherosclerosis. In recent years, various targets have been studied for the treatment of atherosclerosis. PCSK9, a serine protease, actively targets the LDL-R and causes lysosomal degradation, which leads to excessive accumulation of LDL-C. Regulatory T cells (Tregs) and Triggering Receptor Expressed on Myeloid cells-1 (TREM-1) affects the adaptive and innate immune response, respectively, and thus, therapeutic intervention of either of these targets would directly modulate disease progression. Advanced atherosclerotic lesions are characterized by an accumulation of apoptotic cells. Cluster of differentiation-47 (CD47), an anti-phagocytic known as the "don't eat me" signaling molecule, inhibits efferocytosis, which causes accumulation of cell debris in plaque. ADAMTS and Notch signaling potentially affect the formation of neointima by modulation of extracellular matrix components such as macrophages and vascular smooth muscle cells. This review provides insights on the molecular targets for therapeutic intervention of atherosclerosis, their effect at various stages of atherosclerosis development, and the therapies that have been designed and currently being evaluated in clinical trials.

Patient adherence, compliance, and perspectives on evolocumab for the management of resistant hypercholesterolemia

Evolocumab is a PCSK9 inhibitor which is administered subcutaneously, and when added to statin therapy it has been shown to cause a significant incremental LDL-C reduction, leading to a reduction of cardiovascular risk. Evolocumab has a favorable side effect profile, and its self-administration at home appears to be safe and effective with the appropriate training and instructions from a health care provider. Current studies are showing encouraging results regarding adherence to evolocumab in real-life settings, and adherence rates to evolocumab appear to be better than those to statins. However, further larger studies are needed for a more definitive assessment of the short- and long-term patient adherence rates to evolocumab. In addition, reductions in the price of evolocumab may also be necessary to improve cost-effectiveness of the drug.

Eligibility for alirocumab or evolocumab treatment in 1090 hypercholesterolemic patients referred to a regional cholesterol treatment center with LDL cholesterol ≥70 mg/dL despite maximal-tolerated LDL-cholesterol-lowering therapy

Background

Proprotein convertase subtilisin/kexin type 9 inhibitors, Praluent (alirocumab [ALI]) and Repatha (evolocumab [EVO]) have been approved as adjuncts to the standard-of-care maximal-tolerated dose (MTD) of low-density lipoprotein cholesterol (LDLC)-lowering therapy (LLT), statin therapy, in heterozygous (HeFH) (ALI or EVO) or homozygous (EVO) familial hypercholesterolemia, or clinical atherosclerotic cardiovascular disease (CVD) where LDLC lowering is insufficient (both). Since LDLC lowering has been revolutionized by ALI and EVO, specialty pharmaceutical pricing models will be applied to a mass market.

Methods

We applied US Food and Drug Administration (FDA) and insurance eligibility criteria for ALI and EVO to 1090 hypercholesterolemic patients serially referred over 3 years who then received ≥2 months maximal-tolerated dose of standard-of-care LDL cholesterol-lowering therapy (MTDLLT) with follow-up LDLC ≥70 mg/dL. MTDLLT did not include ALI or EVO, which had not been commercially approved before completion of this study.

Results

Of the 1090 patients, 140 (13%) had HeFH by clinical diagnostic criteria and/or CVD with LDLC >100 mg/dL despite ≥2 months on MTDLLT, meeting FDA insurance criteria for ALI or EVO therapy. Another 51 (5%) patients were statin intolerant, without HeFH or CVD.

Conclusion

If 13% of patients with HeFH-CVD and LDLC >100 mg/dL despite MTDLLT are eligible for ALI or EVO, then specialty pharmaceutical pricing models (~$14,300/year) might be used in an estimated 10 million HeFH-CVD patients. Whether the health care savings arising from the anticipated reduction of CVD events by ALI or EVO justify their costs in populations with HeFH-CVD and LDLC >100 mg/dL despite MTDLLT remains to be determined.

PCSK9 and infection: A potentially useful or dangerous association?

Elevated plasma low-density lipoprotein-cholesterol (LDL-C) concentration is the most important risk factor for atherosclerotic cardiovascular diseases (CVDs). Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a ubiquitously expressed serine proteinase which plays a key role in cholesterol metabolism, but has been found to be implicated in some other lipid-independent physiological processes. In this review, the role of PCSK9 was evaluated not only concerning lipid metabolism but also hepatitis C virus (HCV) infection, bacterial infections/sepsis, and septic shock. Collected data from clinical trials revealed that treatment with PCSK9 inhibitors has beneficial effects in lowering LDL-C via inhibition of LDL-receptors (LDL-R), an antiviral effect on HCV infection via down-regulating the surface expression of LDL-R and CD81 on hepatic cells, and a positive association with increased inflammatory responses, as well as with septic shock by down-regulation of hepatocyte LDL-R. On the other hand, PCSK9 inhibition by therapeutic fully humanized antibodies has positive effects in reducing elevated LDL-C. However, their safety and tolerability is an important issue which has to be taken into consideration.

Prevention of cardiovascular disease in patients with familial hypercholesterolaemia: The role of PCSK9 inhibitors

Familial hypercholesterolaemia is an autosomal dominant inherited disorder characterised by elevated low-density lipoprotein cholesterol levels and consequently an increased risk of atherosclerotic cardiovascular disease (ASCVD). Familial hypercholesterolaemia is relatively common, but is often underdiagnosed and undertreated. Cardiologists are likely to encounter many individuals with familial hypercholesterolaemia; however, patients presenting with premature ASCVD are rarely screened for familial hypercholesterolaemia and fasting lipid levels are infrequently documented. Given that individuals with familial hypercholesterolaemia and ASCVD are at a particularly high risk of subsequent cardiac events, this is a missed opportunity for preventive therapy. Furthermore, because there is a 50% chance that first-degree relatives of individuals with familial hypercholesterolaemia will also be affected by the disorder, the underdiagnosis of familial hypercholesterolaemia among patients with ASCVD is a barrier to cascade screening and the prevention of ASCVD in affected relatives. Targeted screening of patients with ASCVD is an effective strategy to identify new familial hypercholesterolaemia index cases. Statins are the standard treatment for individuals with familial hypercholesterolaemia; however, low-density lipoprotein cholesterol targets are not achieved in a large proportion of patients despite treatment. Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors have been shown to reduce low-density lipoprotein cholesterol levels considerably in individuals with familial hypercholesterolaemia who are concurrently receiving the maximal tolerated statin dose. The clinical benefit of PCSK9 inhibitors must, however, also be considered in terms of their cost-effectiveness. Increased awareness of familial hypercholesterolaemia is required among healthcare professionals, particularly cardiologists and primary care physicians, in order to start early preventive measures and to reduce the mortality and morbidity associated with familial hypercholesterolaemia and ASCVD.

PCSK9 inhibitors - from discovery of a single mutation to a groundbreaking therapy of lipid disorders in one decade

Hypercholesterolemia is one of the main risk factors for coronary heart disease and significantly contributes to the high mortality associated with cardiovascular diseases. Statin therapy represents the gold standard in the reduction of low-density lipoprotein cholesterol concentration. Nevertheless, many patients still cannot achieve the recommended target levels, due to either inadequate effectiveness or intolerance of these drugs. Monoclonal antibodies that inhibit proprotein convertase subtilisin/kexin type 9 (PCSK9) have emerged as a promising option in lipid-lowering treatment. After confirmation of their efficacy and safety in clinical trials, evolocumab and alirocumab received approval from the US Food and Drug Administration (FDA) and European Medicines Agency (EMA) for introduction into clinical practice. In this review, we present a history of the development and mechanisms of action, as well as the results of the most important studies concerning PCSK9 inhibitors.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors: Present perspectives and future horizons

AIMS

Our comprehensive review highlights the drug development and pharmacogenomics leading to the recent approval of PCSK9 inhibitors. We also review the anticipated future advances into the uses of PCSK9 inhibition.

BACKGROUND

Despite the present advances in pharmacotherapy, atherosclerotic cardiovascular disease (ASCVD) remains the leading cause of mortality worldwide. Low density lipoprotein-cholesterol (LDL-C) lowering is the primary target for ASCVD risk reduction, showing demonstrable benefits in mortality. However, 70% of events occur even in the presence of statins. This residual risk may be approached with additional LDL-C reduction. Statin intolerance is a common clinical concern affecting adherence and the benefit with statins. There is also significant variation of individual lipid-lowering. Following rapid development, proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors have progressed from genetic observations, to mechanistic studies, to closer realization of the goal of CVD risk reduction. This review discusses the science behind PCSK9 inhibition, evidence of trials involving efficacy and safety, and reflections of its present and future role in clinical care, especially in high-risk patients with ASCVD, persons with suboptimal responses to statins and familial hyperlipidemia. Monoclonal antibodies have demonstrated LDL-C lowering of up to 57% as monotherapy and up to 73% when added to statins. Statins have limited efficacy in reduction of LDL-C due to an increased number of LDL-receptors. Elevated lipoprotein (a) levels may also be significantly lowered by PCSK9i. The journey from discovery to PSCK9 target validation took less than five years, and development and approval of therapeutic modalities for PCSK9 inhibitors happened over the next seven. This review highlights the drug development and pharmacogenomics leading to the recent approval of two agents, alirocumab and evolocumab, with a third bococizumab, and other novel approaches to the pathway pending.

DATA SYNTHESIS

We searched MEDLINE database via Pubmed for reviews, research publications and relevant trials available on PCSK9 inhibition.

CONCLUSION

Despite decades of medical advances, ASCVD remains one of the major causes of morbidity and mortality worldwide. Statin use has multiplied since the validation of LDL hypothesis, however, it is undeniable a more effective and well-tolerated agent is needed in significant number or patients. With the arrival of the era of unprecedented CV protection with PCSK9 inhibition, this exciting new therapy holds a pivotal promise as the future of lipid management. The data available already indicate safety, tolerability and superb efficacy of these agents, which are already changing contemporary cholesterol management. The rapid translation of innovative basic science research into drug development may lead to CV outcomes reduction and confirm that this pathway will become prominently utilized.

Managing the lipid profile of coronary heart disease patients

INTRODUCTION

Lipid profile management is even more critical in patients treated for secondary prevention, since patients with established coronary heart disease are at higher risk of developing events. Current guidelines encourage lifestyle modification and patient engagement in disease prevention. However, the American College of Cardiology/American Heart Association guidelines seem to differ considerably from their predecessors, having an impact on clinical practice of lipid management. Area covered: This review article discusses and provides a summary of the current recommendations for lipid profile management in patients with coronary heart disease, with a view to present lifestyle modification and novel treatment strategies, and to indicate areas of dispute among recent guidelines. Expert commentary: Existing controversies between current guidelines concerning treatment goals and therapeutic decisions may have potential implications on the clinical management of patients. In the meantime, we eagerly wait for the results of randomized controlled trials evaluating promising, potent, safe and prolonged drugs that are in progress.

PCSK9 inhibitors and their role in high-risk patients in reducing LDL cholesterol levels: alirocumab

In this review, we examine alirocumab (Praluent(®)), a monoclonal antibody to PCSK9 and its role in reducing LDL-C levels. By comparing the results of various studies and trials we discuss the efficacy and safety of alirocumab. We aim to guide clinicians of the role of alirocumab in clinical practice. Overall, PCSK9 inhibitors are promising new agents in further reducing LDL-C levels in addition to diet and maximally tolerated statin therapy. Long-term outcome studies are currently ongoing and will further delineate the role of PCSK9 inhibitors.

Cutting-edge mass spectrometry methods for the multi-level structural characterization of antibody-drug conjugates

Antibody drug conjugates (ADCs) are highly cytotoxic drugs covalently attached via conditionally stable linkers to monoclonal antibodies (mAbs) and are among the most promising next-generation empowered biologics for cancer treatment. ADCs are more complex than naked mAbs, as the heterogeneity of the conjugates adds to the inherent microvariability of the biomolecules. The development and optimization of ADCs rely on improving their analytical and bioanalytical characterization by assessing several critical quality attributes, namely the distribution and position of the drug, the amount of naked antibody, the average drug to antibody ratio, and the residual drug-linker and related product proportions. Here brentuximab vedotin (Adcetris) and trastuzumab emtansine (Kadcyla), the first and gold-standard hinge-cysteine and lysine drug conjugates, respectively, were chosen to develop new mass spectrometry (MS) methods and to improve multiple-level structural assessment protocols.