Long-term safety, tolerability, and efficacy of evolocumab in patients with heterozygous familial hypercholesterolemia

Efficacy of Proprotein Convertase Subtilisin/Kexin Type 9 Inhibitors in Patients with Heterozygous Familial Hypercholesterolemia: A Meta-analysis

BACKGROUND

Patients with heterozygous familial hypercholesterolemia (HeFH) are at high risk of major adverse cardiovascular events (MACE) and mortality. Proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i), including monoclonal antibodies (alirocumab, evolocumab) and small interfering RNA (inclisiran), substantially reduce lipid levels. This meta-analysis aimed to evaluate the efficacy of both types of PCSK9i specifically in patients with HeFH.

METHODS

A librarian-assisted systematic search of MEDLINE, Embase, CENTRAL, and ClinicalTrials.gov was performed from 2013 to 2023. Randomized controlled trials of PCSK9i versus control in patients with HeFH were included. No language restrictions were applied. Cochrane Risk-of-Bias tool 2 was used to assess quality of evidence. Meta-analyses were performed using Cochrane ReviewManager. Outcomes included change in atherogenic lipids, MACE, and all-cause death.

RESULTS

Seven trials were included (N = 2196). Overall risk of bias was mostly low or with some concerns. Median follow-up was 24 weeks. PCSK9i had an uncertain effect on MACE (odds ratio [OR] 1.25, 95% confidence interval [CI] 0.69-2.26) and all-cause death (OR 2.47, 95% CI 0.33-18.26) due to the low event rate and short follow-up. However, PCSK9i significantly reduced low-density lipoprotein cholesterol (LDL-C) by 54% (95% CI 49-58), apolipoprotein B by 43% (95% CI 37-49), and lipoprotein(a) by 20% (95% CI 13-28).

CONCLUSIONS

In patients with HeFH, PCSK9i significantly reduced atherogenic lipids (LDL-C, apolipoprotein B, and lipoprotein[a]). Despite this, the effect on MACE or all-cause death was unclear. Larger-scale randomized controlled trials of longer duration are needed to validate whether this short-term reduction in lipid levels translates into a reduction in clinically meaningful outcomes.

The therapeutic effect of PCSK9 inhibitors on dyslipidemia: one-year follow up

Despite the availability of statins and lifestyle modifications, many patients with Dyslipidemia struggle to achieve optimal low-density lipoprotein cholesterol (LDL-C) control. PCSK9 inhibitors offer a promising new therapeutic option with superior LDL-C lowering efficacy compared to statins. However, data on their real-world use, particularly in Iran, is limited. This study aims to address this gap by investigating the one-year effects of evolocumab on lipid profiles and potential cardiovascular outcomes in Iranian patients with Familial Hypercholesterolemia (FH).This single-center, prospective study evaluated evolocumab effectiveness in lowering LDL-C in 50 Iranian adults with FH. Participants with a documented LDL-C > 190 mg/dL on existing cholesterol medications (excluding PCSK9 inhibitors) and a clinical FH diagnosis was included. After baseline assessments (medical history, demographics, lipid profile), evolocumab was administered subcutaneously every two weeks for one year. Follow-up assessments at year one measured changes in LDL-C, high-density lipoprotein cholesterol (HDL-C), and triglycerides. The study enrolled 50 participants with an average age of 55 years old (range 35-80 years).Treatment with evolocumab led to significant improvements in lipid profiles at all follow-up points compared to baseline. On average, LDL-C levels decreased by 105.24 mg/dL, triglycerides decreased by 59.20 mg/dL, and HDL-C levels increased by a modest but significant 4.5 mg/dL after one year(p<0.001). Subgroup analysis revealed no statistically significant interactions between baseline demographics (age, sex, BMI) or lifestyle habits (smoking, alcohol) and changes in lipid levels(p>0.05). However, a significant interaction emerged between baseline lipid levels and their corresponding reductions, suggesting greater improvement in patients with higher baseline values(p<0.05). It is noteworthy that no new cardiovascular events were reported during the study period. This study demonstrates the effectiveness of evolocumab in improving lipid profiles in Iranian patients with FH. The observed reductions in LDL-C and triglycerides, along with a modest increase in HDL-C, suggest potential benefits for cardiovascular risk reduction. The absence of new cardiovascular events during the study is encouraging, but further research with larger and longer-term follow-up is needed to confirm these findings and assess the long-term safety and impact on quality of life.

Established and Emerging Nucleic Acid Therapies for Familial Hypercholesterolemia

Familial hypercholesterolemia (FH) is a genetic disease that leads to elevated low-density lipoprotein cholesterol levels and risk of coronary heart disease. Current therapeutic options for FH remain relatively limited and only partially effective in both lowering low-density lipoprotein cholesterol and modifying coronary heart disease risk. The unique characteristics of nucleic acid therapies to target the underlying cause of the disease can offer solutions unachievable with conventional medications. DNA- and RNA-based therapeutics have the potential to transform the care of patients with FH. Recent advances are overcoming obstacles to clinical translation of nucleic acid-based medications, including greater stability of the formulations as well as site-specific delivery, making gene-based therapy for FH an alternative approach for treatment of FH.

Safety profile of proprotein convertase subtilisin/kexin type 9 inhibitors alirocumab and evolocumab: an updated meta-analysis and meta-regression

BACKGROUND

The use of alirocumab and evolocumab is generally safe and well-tolerated. However, concerns remain about their long-term safety, especially with regard to new-onset or worsening diabetes mellitus (DM). We aim to assess the safety profile of alirocumab and evolocumab compared to comparator.

METHODS

Studies were retrieved comparing the safety of PCSK9i vs. comparator (placebo or statin with or without ezetimibe). The primary outcome was adverse events leading to death. Secondary outcomes included serious adverse events, new onset diabetes mellitus (DM), worsening of DM, neurocognitive dysfunction, creatine kinase (CK) elevation, elevation of liver enzymes and local injection site reaction. Factors associated with the treatment effect were determined by meta-regression analysis. Subgroup analyses were done to explore potential treatment effect differences based on PCSK9i type and treatment duration.

RESULTS

We identified 56 studies with 85,123 adults (29.14% females). PCSK9i was not associated with adverse events that lead to death (OR 0.94, 95% CI 0.84 to 1.04, p = 0.22). Between the two PCSK9i, alirocumab decreased adverse events leading to death (OR 0.79, 95% CI, 0.67 to 0.94, p = 0.008). PCSK9i was associated with less serious events compared to the comparator (OR 0.93, 95% CI 0.89 to 0.98, p < 0.001). This reduction was driven mainly by alirocumab (OR 0.89, 95% CI, 0.85 to 0.93, p < 0.001). Evolocumab worsened DM (OR 2.3, 95% CI 1.26 to 4.2, p = 0.041). Subgroup analysis showed worsening of DM in the first 24 weeks of treatment with odds being highest in the first 12 weeks of treatment (<12 weeks: OR 3.82, 95% CI 1.13 to 12.99, p = 0.03; 12-24 weeks OR 2.12, 95% CI 1.20 to 3.73, p = 0.01. On the other hand, therapy >24 weeks reduced the odds of worsening DM (OR 0.89, 95% CI 0.79 to 0.99, p = 0.04). PCSK9i did not increase cognitive dysfunction, (OR 1.02, 95% CI 0.88 to 1.18, p = 0.76), or cause elevations in liver enzyme (OR 0.91, 95% CI 0.81 to 1.03, p = 0.14), or CK (OR 0.82, 95% CI 0.65 to 1.04, p = 0.10). However, PCSK9i was associated with local injection site reaction (OR 1.54, 95% CI 1.37 to 1.73, p < 0.01).

CONCLUSION

Alirocumab decreased adverse events leading to death. Alirocumab and Evolocumab both decreased serious adverse events. PCSK9i did not increase new onset DM however evolocumab worsened DM in the first 24 weeks of treatment. PCSK9i did not increase neurologic dysfunction, and did not elevate liver enzymes and CK, however it was associated with local injection site reaction.

Long-term safety and effectiveness of alirocumab and evolocumab in familial hypercholesterolemia (FH) in Belgium

Background: In 2019, the European Atherosclerosis Society (EAS) published updated guidelines, recommending even lower blood cholesterol targets than previously. In patients with familial hypercholesterolaemia (FH), who have very elevated blood cholesterol levels and are at ('Very') 'High risk' of atherosclerotic cardiovascular disease (ASCVD), this represents a real challenge. Anti-Proprotein convertase subtilisin/kexin type 9 monoclonal antibody (anti-PCSK9 mAb) has been commercially available for FH in Belgium since 2015. Our study aims to investigate the real-life efficacy of anti-PCSK9 mAb in FH patients. Method: We sourced patients from the EAS FH Studies Collaboration database (an international database on FH in which Belgium participates). We only retained patients using anti-PCSK9 mAb and followed at our Lipid Clinic. Results: Of the 239 subjects included in this study (mean age: 56 years), 85% were considered at 'Very High Risk' (56% with a history of ASCVD), the remaining 15% were at 'High Risk'. The PCSK9 mAb treatment reduced LDL-C levels by 54% within the first year. This reduction was maintained over the follow-up (FU) period (3.0 ± 1.8 years). The EAS targets were reached in 50% of the subjects, 93% of whom were also treated with statins. The treatment was very well tolerated. At the end of the observation period, 96% patients continued receiving PCSK9 mAb. Conclusions: Anti-PCSK9 mAb are a safe and effective therapeutic option for lowering LDL-C levels in FH patients. It allowed a significant portion of our FH patients to reach their lipid targets, mainly in those with combined therapy with statin and/or ezetimibe.

Role of PCSK9 inhibitors in the management of dyslipidaemia

Proprotein convertase subtilisin kexin9 (PCSK9) inhibitors are novel agents that lower LDL cholesterol and reduce cardio-vascular event rate. Being expensive, these agents are reserved for those with high risk or very high risk of CV events and with suboptimal response to statins and ezetimibe, with or without bempedoic acid or those intolerant to statins.

Multizonal observational study conducted by clinical practitioners on Repatha® use in patients with hyperlipidemia (ZERBINI): Colombian results

BACKGROUND

Cardiovascular disease (CVD) represents the primary cause of death and disability globally, with elevated cholesterol as one of the leading risk factors for CVD. We describe the clinical characteristics, treatment patterns, and effectiveness of evolocumab in treating hyperlipidemia.

METHODS

Observational study conducted through a chart review of patients with hyperlipidemia receiving evolocumab as part of clinical management in Colombia.

RESULTS

This study included 115 patients treated with evolocumab. A total of 101 patients (87.8%) had a history of CVD, 13 (11.3%) familial hypercholesterolemia (FH), and 23 (20%) type 2 diabetes. Thirty-nine patients reported intolerance to any statin (33.9%). The median value of LDL-C before initiation of evolocumab was 147mg/dL (IQR: 122.5-183.7mg/dL). Within the first 3 months of treatment, LDL-C value dropped to a median value of 53mg/dL (IQR: 34.0-95.5mg/dL), showing a reduction of 63.9%. The median LDL-C values remained below 45mg/dL until the end of follow-up. Among the patients with available data, up to 61% achieved an LDL-C level below 55mg/dL at the 10-12-month follow-up. A total of 72% of patients were persistent with treatment. Safety results showed a low frequency of hospitalizations (≤2%) and treatment-emergent adverse drug reactions (5.2%). No serious adverse events were reported.

CONCLUSIONS

Evolocumab was associated with reductions in LDL-C levels, with a relative decrease of 63.9% within the first 3 months of treatment. Low rates of interruptions due to adverse events and adequate medication persistence was reported.

Comparison of the burden of familial hypercholesterolemia between two cohorts of French Canadians hospitalized 25 years apart for coronary heart disease

BACKGROUND

Familial hypercholesterolemia (FH) is associated with lifelong elevated plasma concentrations of low-density lipoprotein cholesterol (LDL-C) and high risk of premature coronary heart disease (CHD). Clinical recommendations and treatments have emerged to facilitate the management of FH patients. Their impact on the burden of FH is however not well documented.

OBJECTIVE

To compare the burden of FH between patients hospitalized for a CHD event 25 years apart in the French-Canadian founder population.

METHODS

Lipid profiles, cardiovascular risk factors, treatments and FH status of 2,029 patients consecutively hospitalized for an acute CHD event between 2017 and 2022 (2022 Cohort) were compared to those of 2,506 patients with angiographically-confirmed CHD who were admitted between 1995 and 1998 (1998 Cohort).

RESULTS

At the time of admission, 24.6 % of CHD patients had LDL-C levels >5.0 mmol/L in 1998 compared to 1.4 % in 2022, and FH was diagnosed in 9.6 % of patients in the 1998 cohort compared to 5.5 % in 2022 (p<0.001). FH patients hospitalized for a CHD event were older in 2022 than in 1998 (p <0.001). The prevalence of premature CHD requiring a hospitalization significantly decreased from 1998 to 2022 (64.3% vs. 44.1 %, p<0.001). At the moment of admission, 18.2 % of FH patients had LDL-C concentration <2.0 mmol/L in 2022 vs 0 % in 1998 (p <0.001).

CONCLUSIONS

Over 25 years, FH patients tend to be older and contribute to a lower proportion of hospitalizations for CHD in the French-Canadian founder population. Despite significant improvement in diagnosis and treatment, FH management remains however sub-optimal.

Real-World Effectiveness of PCSK9 Inhibitors in Reducing LDL-C in Patients With Familial Hypercholesterolemia in Italy: A Retrospective Cohort Study Based on the AIFA Monitoring Registries

Background Information on the real-world use of proprotein convertase subtilisin kexin 9 inhibitors (PCKS9is) in familial hypercholesterolemia are limited. We evaluated the pattern of prescription and the long-term efficacy of alirocumab and evolocumab in Italian patients with familial hypercholesterolemia in clinical practice. Methods and Results The data set for analysis was extracted from the PCKS9i Italian Medicines Agency (AIFA) registry and included 2484 patients with heterozygous familial hypercholesterolemia (HeFH) and 62 patients with homozygous familial hypercholesterolemia (HoFH) who were prescribed PCKS9is from February 2017 to December 2021. As the follow-up schedules were not prespecified and could vary, persistence and adherence as well as low-density lipoprotein cholesterol (LDL-C) changes during 2 years of treatment were analyzed in a final cohort of 1299 patients with familial hypercholesterolemia. At baseline, 53.8% of patients with HeFH and 69.4% of patients with HoFH were receiving maximally tolerated lipid-lowering therapies, while 45.9% of patients with HeFH and 30.7% of patients with HoFH reported statin intolerance; mean LDL-C was 197.7±52.3 mg/dL in HeFH and 252.0±106.2 mg/dL in HoFH. The 6-month persistence and adherence to therapy were >85%, and LDL-C reduction reached 58.6% (to 79.7 mg/dL) in HeFH and 57.6% (to 95.1 mg/dL) in HoFH after 24 months of treatment. The European Atherosclerosis Society/European Society of Cardiology LDL-C goals were achieved in 43.3% of patients with HeFH and 37.5% of patients with HoFH. Conclusions PCKS9i prescribed to patients with familial hypercholesterolemia in clinical practice showed LDL-C-lowering efficacy similar to that observed in controlled trials. However, 2 of 5 HeFH cases and 2 of 6 HoFH cases achieved the recommended LDL-C goals. The full achievement of European Atherosclerosis Society/European Society of Cardiology LDL-C goals should require a lower threshold for PCKS9i initiation and a combination of multiple therapies.

The Effect of PCSK9 Inhibition on the Stabilization of Atherosclerotic Plaque Determined by Biochemical and Diagnostic Imaging Methods

Atherosclerosis is a multifactorial, progressive, chronic inflammatory disease. Ultrasound and magnetic resonance imaging are the most accurate predictors of atherosclerotic plaque instability (MRI). Cytokines such as osteopontin, osteoprotegerin, and metalloproteinase 9 could be used as the most recent markers to identify and track the efficacy of anti-atherosclerotic therapy. Patients with USG and MRI-verified unstable atherosclerotic plaque were included in the study. Biomarker concentrations were measured and compared before and after PCSK9 inhibitor therapy. Additionally, concentrations prior to treatment were correlated with MRI images of the carotid artery. After treatment with alirocumab, the concentrations of MMP-9 (p < 0.01) and OPN, OPG (p < 0.05) decreased significantly. Furthermore, the results of OPN, OPG, and MMP 9 varied significantly depending on the type of atherosclerotic plaque in the MRI assay. In stable atherosclerotic plaques, the concentrations of OPN and OPG were greater (p < 0.01), whereas the concentration of MMP9 correlated with the instability of the plaque (p < 0.05). We demonstrated, probably for the first time, that alirocumab therapy significantly decreased the serum concentration of atherosclerotic plaque markers. In addition, we demonstrated the relationship between the type of atherosclerotic plaque as determined by carotid MRI and the concentration of these markers.

Recent advances in the management and implementation of care for familial hypercholesterolaemia

Familial hypercholesterolaemia (FH) is a common autosomal semi-dominant and highly penetrant disorder of the low-density lipoprotein (LDL) receptor pathway, characterised by lifelong elevated levels of low-density lipoprotein cholesterol (LDL-C) and increased risk of atherosclerotic cardiovascular disease (ASCVD). However, many patients with FH are not diagnosed and do not attain recommended LDL-C goals despite maximally tolerated doses of potent statin and ezetimibe. Over the past decade, several cholesterol-lowering therapies such as those targeting proprotein convertase subtilisin/kexin type 9 (PCSK9) or angiopoietin-like 3 (ANGPTL3) with monoclonal antibody or ribonucleic acid (RNA) approaches have been developed that promise to close the treatment gap. The availability of new therapies with complementary modes of action of lipid metabolism has enabled many patients with FH to attain guideline-recommended LDL-C goals. Emerging therapies for FH include liver-directed gene transfer of the LDLR, vaccines targeting key proteins involved in cholesterol metabolism, and CRISPR-based gene editing of PCSK9 and ANGPTL3, but further clinical trials are required. In this review, current and emerging treatment strategies for lowering LDL-C, and ASCVD risk-stratification, as well as implementation strategies for the care of patients with FH are reviewed.

Exploring the Efficacy of Alirocumab and Evolocumab in Reducing Low-Density Lipoprotein (LDL) Cholesterol Levels in Patients With Familial Hypercholesterolemia: A Systematic Review

Patients with familial hypercholesterolemia (FH) have an increased risk of having abnormally high low-density lipoprotein cholesterol (LDL-C) levels. One of the main groups of drugs used for FH is statins. However, even with statins, most patients with FH do not achieve their pre-defined therapeutic LDL-C goals. Therefore, proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) serve to decrease LDL-C levels in that population. A total of 838 articles were found after searching the databases of PubMed, MEDLINE, and Cochrane Library. After including only full-text peer-reviewed articles published in the last 10 years, 67 articles remained. Thirteen articles were put through the Cochrane bias assessment tool to screen for bias. After a strict quality assessment based on the criteria, eight articles were extracted and included in this systematic review. The data extraction from these studies showed that alirocumab and evolocumab were efficacious in decreasing LDL-C levels and achieving the pre-defined LDL-C goals. Many parameters influenced the strength of the LDL-C reduction: sample size of the population, genetic structure of the patients affected by FH, length of the trial, or baseline lipid-lowering therapy used. Therefore, one must consider several other factors while evaluating the percent reduction of PCSK9i. This review is limited because it did not comment on these drugs' cardiovascular outcomes or mortality benefits. In addition, some of the articles used in this systematic review have small sample sizes and short trial times, limiting the long-term evaluation of these drugs.

PCSK9 Inhibitors in the Management of Cardiovascular Risk: A Practical Guidance

Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors are potent medications in the toolkit for treatment of atherosclerotic cardiovascular disease. These agents have been well studied in clinical trials supporting their efficacy in dramatically reducing low-density lipoprotein cholesterol (LDL-C) and impact on cardiovascular outcomes. Since the approval of commercial use for PCSK9 inhibitors in 2015, we have also gained significant experience in the use of these therapeutics in the real-world setting. In this article, we review current guideline recommendations, clinical trial evidence on efficacy and safety as well as data on cost-effectiveness, prescription and adherence. We focus primarily on the monoclonal antibody class of PCSK9 inhibitors in this review while also touching on other types of therapeutics that are under development.

Musculoskeletal Adverse Events Associated with PCSK9 Inhibitors: Disproportionality Analysis of the FDA Adverse Event Reporting System

Background. Some studies suggest that potential safety issues about PCSK9 inhibitors have not been sufficiently explored in clinical trials, including musculoskeletal adverse events (MAEs). Objective. To examine the association between use of PCSK9 inhibitors with and without concurrent statins and risk of MAEs. Patients and Methods. FDA Adverse Event Reporting System (FAERS) dataset of PCSK9 inhibitors and statins from October 2015 to June 2021 was queried. The reporting odds ratio (ROR) with relevant 95% confidence interval (95% CI) was calculated as the index of disproportionality. Outcome of MAEs of different PCSK9 inhibitors regimens was also investigated. Results. 3,185 cases of PCSK9 inhibitor-associated MAEs were recorded. PCSK9 inhibitor class alone demonstrated a strong link to MAEs (ROR 5.92; 95% CI 5.70-6.15), and evolocumab was associated with more reports of MAEs than alirocumab. Concomitant use with statins leaded to an increased occurrence of MAEs (ROR 32.15 (25.55-40.46)), and the risk differed among different statins. The PCSK9 inhibitors were safer than statins in terms of hospitalization rate and death rate (15.64% vs. 36.83%; 0.72% vs. 3.53%). Conclusions. This pharmacovigilance investigation suggests that PCSK9 inhibitors are associated with MAEs. The risk significantly increases when combined with statins. Increased laboratory and clinical monitoring are required to timely diagnose and manage MAEs.

Real-world data on the prescription of proprotein convertase subtilisin/kexin type 9 inhibitors in high-risk patients in a tertiary medical center

Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, alirocumab and evolocumab, are currently approved for clinical use by Taiwan National Health Insurance (NHI) in patients who had a recent atherosclerotic cardiovascular disease with persistent LDL-C levels >135 mg/dL despite high-intensity statin (HIS) or maximally tolerated statin in combination with ezetimibe treatment. Since January 2020 to July 2020, total of 10 patients who had received coronary revascularization received NHI-approved alirocumab or evolocumab in our institution. The mean reduction of LDL-C following PCSK9 inhibitors treatment at 6-month and 12-month were respectively 62.5% and 60.2%. The patients in our study were younger, had more frequently received HIS/ezetimibe, and had higher baseline LDL-C levels with a greater LDL-C reduction following PCSK9 inhibitors treatment compared with those patients in previously studies. Our findings highlight that the NHI's regulation of PCSK9 inhibitors application should be re-evaluation to increase the use of NHI-approved PCSK9 inhibitors in high-risk patients.

The PCSK9 discovery, an inactive protease with varied functions in hypercholesterolemia, viral infections, and cancer

In 2003, the sequences of mammalian proprotein convertase subtilisin/kexin type 9 (PCSK9) were reported. Radiolabeling pulse-chase analyses demonstrated that PCSK9 was synthesized as a precursor (proPCSK9) that undergoes autocatalytic cleavage in the endoplasmic reticulum into PCSK9, which is then secreted as an inactive enzyme in complex with its inhibitory prodomain. Its high mRNA expression in liver hepatocytes and its gene localization on chromosome 1p32, a third locus associated with familial hypercholesterolemia, other than LDLR or APOB, led us to identify three patient families expressing the PCSK9 variants S127R or F216L. Although Pcsk9 and Ldlr were downregulated in mice that were fed a cholesterol-rich diet, PCSK9 overexpression led to the degradation of the LDLR. This led to the demonstration that gain-of-function and loss-of-function variations in PCSK9 modulate its bioactivity, whereby PCSK9 binds the LDLR in a nonenzymatic fashion to induce its degradation in endosomes/lysosomes. PCSK9 was also shown to play major roles in targeting other receptors for degradation, thereby regulating various processes, including hypercholesterolemia and associated atherosclerosis, vascular inflammation, viral infections, and immune checkpoint regulation in cancer. Injectable PCSK9 monoclonal antibody or siRNA is currently used in clinics worldwide to treat hypercholesterolemia and could be combined with current therapies in cancer/metastasis. In this review, we present the critical information that led to the discovery of PCSK9 and its implication in LDL-C metabolism. We further analyze the underlying functional mechanism(s) in the regulation of LDL-C, as well as the evolving novel roles of PCSK9 in both health and disease states.

Treatment of Dyslipidaemia in Children

Childhood dyslipidaemia is one of the main traditional cardiovascular risk factors that initiate and exacerbate the atherosclerotic process. Healthcare providers may play a key role in the management of children with lipid abnormalities; however, they have to properly evaluate the normal lipid values and know the available treatment options in children and adolescents. Current guidelines recommend healthy behaviours as the first-line treatment for childhood dyslipidaemia. The therapeutic lifestyle changes should focus on dietary modifications, daily physical activity, reduction in body weight and tobacco smoking cessation. Parents play a key role in promoting their children's healthy habits. In children with more severe forms of lipid abnormalities and in those who do not benefit from healthy behaviours, pharmacological therapy should be considered. Safe and effective medications are already available for children and adolescents. Statins represent the first-line pharmacological option, while ezetimibe and bile acid sequestrants are usually used as second-line drugs. Despite their limited use in children, other lipid-lowering agents (already approved for adults) are currently available or under study for certain categories of paediatric patients (e.g., familial hypercholesterolemia). Further studies are needed to evaluate the long-term efficacy, safety and tolerability of novel lipid-lowering drugs, especially in children.

PCSK9 Biology and Its Role in Atherothrombosis

It is now about 20 years since the first case of a gain-of-function mutation involving the as-yet-unknown actor in cholesterol homeostasis, proprotein convertase subtilisin/kexin type 9 (PCSK9), was described. It was soon clear that this protein would have been of huge scientific and clinical value as a therapeutic strategy for dyslipidemia and atherosclerosis-associated cardiovascular disease (CVD) management. Indeed, PCSK9 is a serine protease belonging to the proprotein convertase family, mainly produced by the liver, and essential for metabolism of LDL particles by inhibiting LDL receptor (LDLR) recirculation to the cell surface with the consequent upregulation of LDLR-dependent LDL-C levels. Beyond its effects on LDL metabolism, several studies revealed the existence of additional roles of PCSK9 in different stages of atherosclerosis, also for its ability to target other members of the LDLR family. PCSK9 from plasma and vascular cells can contribute to the development of atherosclerotic plaque and thrombosis by promoting platelet activation, leukocyte recruitment and clot formation, also through mechanisms not related to systemic lipid changes. These results further supported the value for the potential cardiovascular benefits of therapies based on PCSK9 inhibition. Actually, the passive immunization with anti-PCSK9 antibodies, evolocumab and alirocumab, is shown to be effective in dramatically reducing the LDL-C levels and attenuating CVD. While monoclonal antibodies sequester circulating PCSK9, inclisiran, a small interfering RNA, is a new drug that inhibits PCSK9 synthesis with the important advantage, compared with PCSK9 mAbs, to preserve its pharmacodynamic effects when administrated every 6 months. Here, we will focus on the major understandings related to PCSK9, from its discovery to its role in lipoprotein metabolism, involvement in atherothrombosis and a brief excursus on approved current therapies used to inhibit its action.

Current Approach to the Diagnosis and Treatment of Heterozygote and Homozygous FH Children and Adolescents

Purpose of Review

To elucidate the current approach of care in pediatric patients with familial hypercholesterolemia (FH). We sought an answer to the question whether the advances and major changes in lipid management are relevant and apply to children and adolescents.

Recent Findings

Latest research findings clearly demonstrate that lowering cholesterol levels at a young age prevents vascular atherosclerotic changes and decreases cardiovascular events in adulthood and emphasizes the importance of early detection and intervention in the pediatric FH patients group.

Summary

FH is a common genetic disease caused by mutations in genes associated with the metabolism of low-density lipoproteins (LDL). The hallmark of FH is elevated LDL cholesterol (LDL-C) levels from birth and premature atherosclerotic cardiovascular disease (ASCVD). Often FH is either undiagnosed or diagnosed with a considerable delay, leading to vascular atherosclerotic changes and cardiovascular disease. Prompt identification of FH subjects is essential, to initiate early preventive measures. Safe and efficient pharmacological agents are approved for use in children and adolescents. Statins are the first line of therapy, in combination of ezetimibe. Unfortunately, these drugs do not warrant the achievement of therapeutic target, especially in HoFH patient. In the latter, lipoprotein apheresis (LA), which has been shown to be safe and effective, is strongly recommended. Finally, the new drugs still under study will allow a multimodal customized treatment. Lowering cholesterol levels at a young age hinders vascular atherosclerotic changes decreasing cardiovascular events in adulthood. Therefore, early detection, diagnosis, and intervention in FH patients are priority objectives.

Efficacy of PCSK9 inhibitors in the treatment of heterozygous familial hypercholesterolemia: A clinical practice experience

BACKGROUND

PCSK9 inhibitors are a treatment option for patients with familial hypercholesterolemia not on low-density lipoprotein cholesterol goals despite the use of maximally tolerated high intensity-statins dose.

OBJECTIVE

To evaluate the efficacy of alirocumab and evolocumab in LDL-C reduction and targets attainment in patients with heterozygous familial hypercholesterolemia in clinical practice setting.

METHODS

SAFEHEART is an open, long-term prospective study of a cohort of subjects with molecular diagnosis of familial hypercholesterolemia. This study analyze subjects ≥ 20 years of age on stable lipid-lowering therapy, who received PCSK9 inhibitors during the period 2016 to January 2020.

RESULTS

433 patients (mean age 55 years, 53% male, 39% with cardiovascular disease) were included and followed-up for a median of 2.5 years (IQR 1.6-3.0). Median LDL-C level prior to PCSK9 inhibitors was 145 mg/dL (IQR 125-173). The addition of PCSK9 inhibitors (211 alirocumab, 222 evolocumab) reduced LDL-C by 58% (IQR 41-70) p<0.001, in men and women, achieving a median LDL-C level of 62 mg/dL (IQR 44-87) without differences between both PCSK9 inhibitors. Out of them 67% with and 80% without cardiovascular disease reached 2016 ESC/EAS LDL-C targets, and 46% very high risk and 50% high risk patients achieved 2019 ESC/EAS LDL-C goals. Independent predictor factors for attainment of 2019 ESC/EAS LDL-C goals were to be male, smoking and the use of statins with ezetimibe. Both inhibitors were well tolerated.

CONCLUSIONS

PCSK9 inhibitors on top of maximum lipid-lowering treatment significantly reduced LDL-C levels in patients with familial hypercholesterolemia and improved the achievement of LDL-C targets.

Novel therapies for familial hypercholesterolemia

PURPOSE OF REVIEW

Familial hypercholesterolemia is a genetic disorder of defective clearance and subsequent increase in serum LDL cholesterol (LDL-C) with a resultant increased risk of premature atherosclerotic cardiovascular disease. Despite treatment with traditional lipid-lowering therapies (LLT), most patients with familial hypercholesterolemia are unable to achieve target LDL-C. We review current and future novel therapeutic options available for familial hypercholesterolemia.

RECENT FINDINGS

The use of proprotein convertase subtilisin kexin type 9 (PCSK9) inhibitors are effective in lowering LDL-C in patients with familial hypercholesterolemia, with a reduction in LDL-C of 60% in heterozygous familial hypercholesterolemia (HeFH) and up to 35% in homozygous familial hypercholesterolemia (HoFH). Inclisiran, another novel agent, is a small-interfering ribonucleic acid that reduces hepatic production of PCSK9 to provide a prolonged and sustained reduction in LDL-C of nearly 50% in HeFH. However, both agents require LDL receptor (LDLR) activity. Evinacumab, a novel monoclonal antibody against angiopoetin-like 3 (ANGPTL3), reduces LDL-C by 50% independent of LDLR activity.

SUMMARY

Achieving a target LDL-C in familial hypercholesterolemia can be challenging with standard LLT; however, novel therapeutic modalities show remarkable reductions in LDL-C allowing nearly all patients with HeFH and a significant proportion of patients with HoFH to achieve acceptable LDL-C levels.

Safety and efficacy of alirocumab in a real-life setting: the ODYSSEY APPRISE study

Aims

To obtain safety and efficacy data of alirocumab, a proprotein convertase subtilisin/kexin type 9 inhibitor, in a real-life setting in high cardiovascular (CV) risk patients with heterozygous familial hypercholesterolaemia (HeFH) or very-high low-density lipoprotein cholesterol (LDL-C) levels despite maximally tolerated dose of statin ± other lipid-lowering therapies (MTD ± LLTs). ODYSSEY APPRISE was a prospective, single-arm, Phase 3b open-label (≥12 weeks to ≤ 30 months) European/Canadian study with alirocumab.

Methods and results

Patients received alirocumab 75 or 150 mg every 2 weeks, with dose adjustment based on physician’s judgment. In total, 994 patients were enrolled and treated. The mean [standard deviation (SD)] duration of alirocumab exposure was 72.4 (42.5) weeks. Patients with HeFH were younger [mean (SD) age of 53.8 (11.6) vs. 61.6 (10.1) years], more likely to be female (41.7% vs. 29.1%) and had higher baseline LDL-C compared with non-familial hypercholesterolaemia (non-FH) patients [mean (SD) of 5.1 (1.7) vs. 4.1 (1.1) mmol/L]. The overall incidence of treatment-emergent adverse events (TEAEs) was 71.6%; common TEAEs included nasopharyngitis (7.8%), myalgia (7.1%), and headache (6.2%). At Week 12, mean (SD) LDL-C was reduced by 54.8 (20.1)% from baseline [2.6 (1.2) mmol/L], maintained for the trial duration. LDL-C was reduced below 1.8 mmol/L and/or by ≥50% reduction from baseline in 69.1% of patients overall, and for 64.7 and 77.4% of the HeFH and non-FH subgroups, respectively.

Conclusion

In a real-life setting in patients with hypercholesterolaemia and high CV risk, alirocumab was generally well tolerated and resulted in clinically significant LDL-C reductions.

First national registry on the effectiveness and safety of evolocumab in clinical practice in patients attended in cardiology in Spain. The RETOSS-CARDIO study

OBJECTIVE

To present the first registry used to analyse the clinical profile of patients treated with evolocumab in Spain, including the effectiveness on the lipid profile and safety in the «real world» setting.

METHODS

Multicentre, retrospective, and observational study of patients starting treatment with evolocumab from February 2016 to May 2017 in clinical practice in Spanish cardiology units.

RESULTS

A total of 186 patients (mean age 60.3 ± 9.8 years were included, 35.5% with familial hypercholesterolaemia, and 94.1% with a previous cardiovascular event) from 31 cardiology units. Baseline lipid profile: Total cholesterol 219.4 ± 52.2 mg/dL, LDL-cholesterol 144.0 ± 49.0mg/dL, HDL-cholesterol 47.7 ± 13.0mg/dL, and triglycerides 151.0 ± 76.2mg/dL. At the time of initiating evolocumab, 53.8% of patients were taking statins (50% had partial or total intolerance to statins), and 51.1% ezetimibe. In all cases, the dose of evolocumab used was 140 mg, mainly every 2 weeks (97.3%). Evolocumab compliance was high (92.3%). Treatment with evolocumab was interrupted in 6 patients (3.2%), with only 1 (0.5%) due to a probable side effect. Evolocumab significantly reduced total cholesterol (30.9% at week 2, and 39.3% at week 12; P<.001), LDL cholesterol (44.4% and 57.6%, respectively; P<.001), and triglycerides (14.8% and 5.2%, respectively; P<001), with no significant changes in HDL-cholesterol (6.7% and 2.0%; P=.14).

CONCLUSIONS

In clinical practice, evolocumab is associated with reductions in LDL cholesterol, with nearly 60% after 12 weeks of treatment, and with low rates of interruptions due to side effects and high medication compliance. These results are consistent with those reported in randomised clinical trials.

Cardiovascular Outcomes and Proprotein Convertase Subtilisin/Kexin Type 9 Inhibitors: Current Data and Future Prospects

Cardiovascular (CV) disease remains the leading cause of morbidity and mortality worldwide and poses an ongoing challenge with the aging population. Elevated low-density lipoprotein cholesterol (LDL-C) is an established risk factor for atherosclerotic cardiovascular disease (ASCVD), and the expert consensus is the use of statin therapy (if tolerated) as first line for LDL-C reduction. However, patients with ASCVD may experience recurrent ischemic events despite receiving maximally tolerated statin therapy, including those whose on-treatment LDL-C remains ≥70 mg/dL, patients with familial hypercholesterolemia, high-risk subgroups with comorbidities such as diabetes mellitus, and those who have an intolerance to statin therapy. Optimal therapeutic strategies for this unmet need should deploy aggressive lipid lowering to minimize the contribution of dyslipidemia to their CV risk, particularly for very high-risk populations with additional risk factors beyond hypercholesterolemia and established ASCVD. To understand the current clinical climate and guidelines regarding ASCVD, we primarily searched PubMed for articles published in English regarding lipid-lowering therapies and CV risk reduction, including emerging therapies, and CV outcomes trials with proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors. This review discusses the findings of recent clinical trial evidence for CV risk reduction with cholesterol-lowering therapies, with a focus on CV outcomes trials with PCSK9 inhibitors, and considers the impact of the study results for secondary prevention and future strategies in patients with hypercholesterolemia and CV risk despite maximally tolerated statin therapy.

Novel strategies to target proprotein convertase subtilisin kexin 9: beyond monoclonal antibodies

Since the discovery of the role of proprotein convertase subtilisin kexin 9 (PCSK9) in the regulation of low-density lipoprotein cholesterol (LDL-C) in 2003, a paradigm shift in the treatment of hypercholesterolaemia has occurred. The PCSK9 secreted into the circulation is a major downregulator of the low-density lipoprotein receptor (LDLR) protein, as it chaperones it to endosomes/lysosomes for degradation. Humans with loss-of-function of PCSK9 exhibit exceedingly low levels of LDL-C and are protected from atherosclerosis. As a consequence, innovative strategies to modulate the levels of PCSK9 have been developed. Since 2015 inhibitory monoclonal antibodies (evolocumab and alirocumab) are commercially available. When subcutaneously injected every 2-4 weeks, they trigger a ∼60% LDL-C lowering and a 15% reduction in the risk of cardiovascular events. Another promising approach consists of a liver-targetable specific PCSK9 siRNA which results in ∼50-60% LDL-C lowering that lasts up to 6 months (Phases II-III clinical trials). Other strategies under consideration include: (i) antibodies targeting the C-terminal domain of PCSK9, thereby inhibiting the trafficking of PCSK9-LDLR to lysosomes; (ii) small molecules that either prevent PCSK9 binding to the LDLR, its trafficking to lysosomes or its secretion from cells; (iii) complete silencing of PCSK9 by CRISPR-Cas9 strategies; (iv) PCSK9 vaccines that inhibit the activity of circulating PCSK9. Time will tell whether other strategies can be as potent and safe as monoclonal antibodies to lower LDL-C levels.

Arterial stiffness improvement after adding on PCSK9 inhibitors or ezetimibe to high-intensity statins in patients with familial hypercholesterolemia: A Two-Lipid Center Real-World Experience

BACKGROUND

Familial hypercholesterolemia (FH) is characterized by increased cardiovascular risk; despite-high intensity statins, only few patients with FH achieve the recommended low-density lipoprotein cholesterol (LDL-C) targets.

OBJECTIVE

We aimed to evaluate the effectiveness of six-month add-on therapy with proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9-i) or ezetimibe on lipid profile and pulse wave velocity (PWV) in patients with FH.

METHODS

In this observational study, we evaluated 98 genetically confirmed patients with FH with an LDL-C off-target despite high-intensity statins with or without ezetimibe; of these, 53 patients (statin plus ezetimibe) added PCSK9-i (PCSK9-i group) and 45 (statin only) added ezetimibe (EZE group) per applicable guidelines and reimbursement rules. All patients obtained biochemical analysis and PWV evaluation at baseline and after six months of optimized treatment.

RESULTS

After 6 months of add-on therapy, most patients achieving LDL-C targets were in the PCSK9-i group (77.3% PCSK9-i group vs 37.8% EZE group, P < .001). The PCSK9-i group achieved both a greater LDL-C and PWV reduction than the EZE group [-51% vs -22.8%, P < .001 and -15% vs -8.5%, P < .01, respectively]. In a linear regression analysis, we showed a coefficient (r) of 0.334 for the relationship between ΔPWV and ΔLDL (P < .05); moreover, in an exploratory analysis, the relationship appeared to be stronger in patients with FH without cardiovascular events (r = 0.422, P < .01).

CONCLUSIONS

Lipid and PWV profiles in patients with FH significantly improved after addition of PCSK9-i or ezetimibe to high-intensity statin therapy; moreover, ΔPWV was associated with ΔLDL. Our results are consistent with a beneficial role of these novel therapies in FH subjects.

Barriers to Early Diagnosis and Treatment of Familial Hypercholesterolemia: Current Perspectives on Improving Patient Care

Familial hypercholesterolemia (FH) is a frequent disorder associated with premature atherosclerotic cardiovascular disease. Different clinical diagnosis criteria are available, and cost of genetic testing has been reduced in the last years; however, most cases are not diagnosed worldwide. Patients with FH are at high cardiovascular risk and the risk can be reduced with lifelong lifestyle and pharmacological treatment. Statins and ezetimibe are available as generic drugs in most countries reducing the cost of treatment. However, the use of high-intensity statins combined with ezetimibe and PCSK9 inhibitors, if necessary, is low for different reasons that contribute to a high number of patients not reaching LDL-C targets according to guidelines. On the other hand, cardiovascular risk varies greatly in families with FH; therefore, risk stratification strategies including cardiovascular imaging is another element to consider for improving care and management of FH. There are numerous barriers depending on the awareness, knowledge, perception of risk, management and care of patients living with FH that impact in the diagnosis and treatment of the disorder. In this contemporary review, we analyze different barriers in the diagnosis and care of patients to improve patients’ care and prevention of atherosclerotic cardiovascular disease and describe recent advances and strategies to improve the gaps in the care of FH, including global collaboration and advocacy.

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.

Canadian Cardiovascular Society Position Statement on Familial Hypercholesterolemia: Update 2018

Familial hypercholesterolemia (FH) is the most common monogenic disorder causing premature atherosclerotic cardiovascular disease. It affects 1 in 250 individuals worldwide, and of the approximately 145,000 Canadians estimated to have FH, most are undiagnosed. Herein, we provide an update of the 2014 Canadian Cardiovascular Society position statement on FH addressing the need for case identification, prompt recognition, and treatment with statins and ezetimibe, and cascade family screening. We provide a new Canadian definition for FH and tools for clinicians to make a diagnosis. The risk of atherosclerotic cardiovascular disease in patients with "definite" FH is 10- to 20-fold that of a normolipidemic individual and initiating treatment in youth or young adulthood can normalize life expectancy. Target levels for low-density lipoprotein cholesterol are proposed and are aligned with the Canadian Cardiovascular Society guidelines on dyslipidemia. Recommendation for the use of inhibitors of proprotein convertase kexin/subtilisin type 9 are made in patients who cannot achieve therapeutic low-density lipoprotein cholesterol targets on maximally tolerated statins and ezetimibe. The writing committee used the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology in the preparation of the present document, which offers guidance for practical evaluation and management of patients with FH. This position statement also aims to raise awareness of FH nationally, and to mobilize patient support, promote knowledge translation, and availability of treatment and health care resources for this under-recognized, but important medical condition.

Clinical guidance on the contemporary use of proprotein convertase subtilisin/kexin type 9 monoclonal antibodies

There is now significant evidence for the benefits of lowering low-density lipoprotein cholesterol (LDL-c) to reduce the risk of atherosclerotic cardiovascular disease (ASCVD). Although statins are the most widely prescribed lipid-lowering therapy that effectively lower LDL-c, especially in combination with ezetimibe, some patients require adjunctive therapy to further lower LDL-c and mitigate attendant risk of ASCVD. The gap can be filled by proprotein convertase subtilisin/kexin type 9 (PCSK9) monoclonal antibodies whose use is currently supported by two recent cardiovascular outcome studies and new treatment guidelines. We provide an overview of extant studies investigating PCSK9 monoclonal antibodies in various patient populations, an update of the guidelines regarding their use and a case-based discussion.

Tackling Residual Atherosclerotic Risk in Statin-Treated Adults: Focus on Emerging Drugs

Epidemiological studies and meta-analyses have consistently suggested the importance of lowering low-density lipoprotein cholesterol (LDL-C) to reduce cardiovascular (CV) events. However, these studies and mechanistic studies using intracoronary imaging modalities have reported patients who continue to experience CV events or disease progression despite optimal LDL-C levels on statins. These findings, including statin intolerance, have highlighted the importance of exploring additional potential therapeutic targets to reduce CV risk. Genomic insights have presented a number of additional novel targets in lipid metabolism. In particular, proprotein convertase subtilisin/kexin type 9 inhibitors have rapidly developed and recently demonstrated their beneficial impact on CV outcomes. Triglyceride (TG)-rich lipoproteins have been recently reported as a causal factor of atherosclerotic cardiovascular disease (ASCVD). Indeed, several promising TG-targeting therapies are being tested at various clinical stages. In this review, we present the evidence to support targeting atherogenic lipoproteins to target residual ASCVD risk in statin-treated patients.

Impact of Age on the Efficacy and Safety of Alirocumab in Patients with Heterozygous Familial Hypercholesterolemia

PURPOSE

This post-hoc analysis examined whether age modified the efficacy and safety of alirocumab, a PCSK9 inhibitor, in patients with heterozygous familial hypercholesterolemia (HeFH), using pooled data from four 78-week placebo-controlled phase 3 trials (ODYSSEY FH I, FH II, LONG TERM, and HIGH FH).

METHODS

Data from 1257 patients with HeFH on maximally tolerated statin ± other lipid-lowering therapies were analyzed by an alirocumab dose regimen and by age subgroups (18 to < 45, 45 to < 55, 55 to < 65, and ≥ 65 years). In the FH I and II trials, patients received 75 mg subcutaneously every 2 weeks (Q2W), with dose increase to 150 mg Q2W at week 12 if week 8 low-density lipoprotein cholesterol (LDL-C) was ≥ 70 mg/dl. In HIGH FH and LONG TERM, patients received 150 mg alirocumab Q2W.

RESULTS

Baseline characteristics were similar between treatment groups across all age groups; the proportion of males decreased whereas the proportion of patients with coronary heart disease, diabetes, hypertension, and declining renal function increased with increasing age. Mean LDL-C reductions at week 24 were consistent across age groups (50.6-61.0% and 51.1-65.8% vs. placebo for the 75/150 and 150 mg alirocumab dose regimens, respectively; both non-significant interaction P-values). Treatment-emergent adverse events occurred in similar frequency in alirocumab- and placebo-treated patients regardless of age, except for injection-site reactions, which were more common in alirocumab than placebo but declined in frequency with age.

CONCLUSIONS

Alirocumab treatment resulted in significant LDL-C reductions at weeks 12 and 24 and was generally well tolerated in patients with HeFH across all age groups studied.

PCSK9 inhibition 2018: riding a new wave of coronary prevention

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a hepatic enzyme that regulates the low-density lipoprotein cholesterol (LDL-c) receptor and thus circulating LDL-c levels. With overwhelming evidence now supporting the reduction in LDL-c to lower the risk of cardiovascular disease, PCSK9 inhibitors represent an important therapeutic target, particularly in high-risk populations. Here, we summarise and update the science of PCSK9, including its discovery and the development of various inhibitors, including the now approved monoclonal antibodies. In addition, we summarise the clinical applications of PCSK9 inhibitors in a range of patient populations, as well as the major randomised controlled trials investigating their use in coronary prevention.

Cholesterol transport system: An integrated cholesterol transport model involved in atherosclerosis

Atherosclerosis, the pathological basis of most cardiovascular disease (CVD), is closely associated with cholesterol accumulation in the arterial intima. Excessive cholesterol is removed by the reverse cholesterol transport (RCT) pathway, representing a major antiatherogenic mechanism. In addition to the RCT, other pathways are required for maintaining the whole-body cholesterol homeostasis. Thus, we propose a working model of integrated cholesterol transport, termed the cholesterol transport system (CTS), to describe body cholesterol metabolism. The novel model not only involves the classical view of RCT but also contains other steps, such as cholesterol absorption in the small intestine, low-density lipoprotein uptake by the liver, and transintestinal cholesterol excretion. Extensive studies have shown that dysfunctional CTS is one of the major causes for hypercholesterolemia and atherosclerosis. Currently, several drugs are available to improve the CTS efficiently. There are also several therapeutic approaches that have entered into clinical trials and shown considerable promise for decreasing the risk of CVD. In recent years, a variety of novel findings reveal the molecular mechanisms for the CTS and its role in the development of atherosclerosis, thereby providing novel insights into the understanding of whole-body cholesterol transport and metabolism. In this review, we summarize the latest advances in this area with an emphasis on the therapeutic potential of targeting the CTS in CVD patients.

From lipoprotein apheresis to proprotein convertase subtilisin/kexin type 9 inhibitors: Impact on low-density lipoprotein cholesterol and C-reactive protein levels in cardiovascular disease patients

In this observational study, we compared the effect of lipoprotein apheresis and evolocumab or alirocumab on levels of lipoprotein cholesterol, triglycerides and inflammatory markers (C reactive protein and interleukin 6) in cardiovascular patients ( n = 9). Patients were monitored during the last year of lipoprotein apheresis followed by six months of treatment with proprotein convertase subtilisin/kexin type 9 inhibitors. The biochemical parameters were determined pre- and post- every apheresis procedure for 12 months and then after one, three and six months of treatment with evolocumab (140 mg every two weeks [Q2W]) or alirocumab (75 mg or 150 mg every two weeks [Q2W]). Lipoprotein apheresis significantly reduced low-density lipoprotein cholesterol levels from 138 ± 32 mg/dl to 46 ± 16 mg/dl ( p < 0.001), with an inter-apheresis level of 114 ± 26 mg/dl. Lipoprotein(a) was also reduced from a median of 42 mg/dl to 17 mg/dl ( p < 0.01). Upon anti-proprotein convertase subtilisin/kexin type 9 therapy, low-density lipoprotein cholesterol levels were similar to post-apheresis (59 ± 25, 41 ± 22 and 42 ± 21mg/dl at one, three and six months, respectively) as well as those of lipoprotein(a) (18 mg/dl). However, an opposite effect was observed on high-density lipoprotein cholesterol levels: –16.0% from pre- to post-apheresis and +34.0% between pre-apheresis and proprotein convertase subtilisin/kexin type 9 inhibitors. Apheresis significantly reduced high-sensitivity C-reactive protein levels (1.5 ± 1.2 mg/l pre-apheresis to 0.6 ± 0.6 mg/l post-apheresis), while no changes were found upon proprotein convertase subtilisin/kexin type 9 mAbs administration. In conclusion, our study demonstrated that, by switching from lipoprotein apheresis to anti-proprotein convertase subtilisin/kexin type 9 therapies, patients reached similar low-density lipoprotein cholesterol and lipoprotein(a) levels, increased those of high-density lipoprotein cholesterol, and showed no changes on high-sensitivity C-reactive protein.

Determinants of Achieved LDL Cholesterol and "Non-HDL" Cholesterol in the Management of Dyslipidemias

PURPOSE OF REVIEW

The advent of combination therapy to provide LDL lowering beyond that achieved with statins necessitates the development of greater understanding of how drugs work together, what changes occur in key lipoprotein fractions, and what residual risk remains.

RECENT FINDINGS

Clinical trials of agents that, when added to statins, generate profound LDL lowering have been successful in reducing further the risk of cardiovascular disease. LDL cholesterol can be now decreased to unprecedented levels, so the focus of attention then shifts to other apolipoprotein B-containing, atherogenic lipoprotein classes such as lipoprotein(a) and remnants of the metabolism of triglyceride-rich particles. "Non-HDL cholesterol" is used increasingly (especially if measured in the non-fasting state) as a more comprehensive index of risk. Metabolic studies reveal how current drugs act in combination to achieve profound lipid lowering. However, care is needed in interpreting achieved LDLc and non-HDLc levels in the emerging treatment paradigm.