Homozygous familial hypercholesterolaemia: new insights and guidance for clinicians to improve detection and clinical management. A position paper from the Consensus Panel on Familial Hypercholesterolaemia of the European Atherosclerosis Society

Evinacumab and reduced lipoprotein apheresis in pediatric homozygous familial hypercholesterolemia: a retrospective study on LDL-C

BACKGROUND AND AIMS

Homozygous familial hypercholesterolemia (HoFH) is a rare genetic disorder characterized by severely elevated low-density lipoprotein cholesterol (LDL-C) from birth, leading to accelerated atherosclerotic cardiovascular disease and premature death if untreated. Evinacumab, a monoclonal antibody targeting angiopoietin-like 3 (ANGPTL3), offers an LDL receptor-independent pathway to lower LDL-C. This study aimed to evaluate the effect of evinacumab on lipid levels and its potential to reduce lipoprotein apheresis (LA) frequency in children and adolescents with HoFH.

METHODS

This was a single-center, retrospective, observational study of six patients aged 10-19 years who had genetically confirmed HoFH and were treated with stable doses of lipid-lowering therapy (LLT) and evinacumab with or without LA at the Medical University of Vienna. Demographic characteristics, lipid levels, and treatment details were collected.

RESULTS

At the first visit, LDL-C levels ranged from 521 to 870 mg/dL (13.5-22.5 mmol/L). With stable LLT plus LA, pre-LA LDL-C levels were reduced to 212-352 mg/dL (5.5-9.1 mmol/L) and, after evinacumab was added, further reductions to 90-201 mg/dL (2.3-5.2 mmol/L) were observed. However, during periods of reduced LA frequency, pre-LA LDL-C levels increased to 105-216 mg/dL (2.7-5.6 mmol/L), exceeding the target of 115 mg/dL (3.0 mmol/L) in three out of four patients. LA frequency reduction from weekly to three times per month was only possible in one patient, but no patients had termination of LA.

CONCLUSIONS

Evinacumab effectively lowers LDL-C in children and adolescents with HoFH. However, its ability to facilitate long-term reduction in LA frequency was not shown and remains unclear.

Coagulation in familial hypercholesterolemic patients: effect of current hypolipidemic treatment and anticoagulants

Familial hypercholesterolemia (FH) is a relatively rare genetic disease associated with high serum cholesterol levels but also with abnormalities in blood coagulation. Novel pharmacotherapeutic approaches in FH including proprotein convertase subtilisin/kexin type 9 antibodies (PCSK9Ab) are very efficient in decreasing cholesterol levels but their impact on coagulation in FH is not yet established. Therefore, we hypothesized that these novel antidyslipidemic drugs can positively impact blood coagulation due to their more potent effect on cholesterol. A total of 15 healthy volunteers and all 15 available patients with severe FH treated at the University Hospital Hradec Králové were enrolled, coagulation was assessed by mechanic coagulometer, and the impact of four clinically used direct anticoagulants was analyzed ex vivo. FH patients were treated effectively as their total cholesterol was 4.11 ± 1.57 mM and LDL cholesterol was 2.44 ± 1.46 mM, which were even lower values than detected in our generally healthy controls. Twelve from the 15 FH patients were finally analyzed as 3 were treated with anticoagulants. Coagulation in FH patients was prolonged more extensively by dabigatran and rivaroxaban, when compared to healthy controls. Treatment with PCSK9Ab or lipid apheresis did not seem to have a significant effect on coagulation. The latter procedure however significantly decreased serum levels of one vitamin K form, MK4. Shorter coagulation time was associated with higher levels of LDL, non-HDL, and total cholesterol. Current treatment of FH seems to improve the effects of direct anticoagulants beyond known effects on LDL cholesterol levels.

Efficacy and Safety of Inclisiran in Adolescents With Genetically Confirmed Homozygous Familial Hypercholesterolemia: Results From the Double-Blind, Placebo-Controlled Part of the ORION-13 Randomized Trial

BACKGROUND

Homozygous familial hypercholesterolemia (HoFH) is a genetic disease characterized by high levels of low-density lipoprotein cholesterol (LDL-C) present from birth, leading to early-onset and progressive atherosclerotic cardiovascular disease. Early treatment initiation is crucial for cardiovascular risk reduction; however, many patients do not reach LDL-C treatment goals. Inclisiran, a small interfering RNA targeting hepatic PCSK9 (proprotein convertase subtilisin/kexin type 9), is effective and well tolerated in adult patients with hyperlipidemia; however, it has not yet been studied in pediatric patients.

METHODS

Herein we report results of the 1-year, double-blind, placebo-controlled part of the phase 3 study ORION-13 (Study to Evaluate Efficacy and Safety of Inclisiran in Adolescents With Homozygous Familial Hypercholesterolemia) in adolescents with HoFH. This 2-part multicenter study included 13 patients ≥12 to <18 years of age with a genetic diagnosis of HoFH (excluding LDL [low-density lipoprotein] receptor [LDLR] null/null genotypes) and elevated LDL-C levels (>130 mg/dL) on maximally tolerated statin treatment, with or without other lipid-lowering therapies. Eligible patients were randomized 2:1 to receive either 300 mg of inclisiran sodium or placebo, administered on days 1, 90, and 270. The primary end point was the mean percentage change in LDL-C from baseline to day 330.

RESULTS

The mean age of patients was 14.8 years, and mean baseline LDL-C was 272 mg/dL. The placebo-adjusted mean (95% CI) percentage change in LDL-C from baseline to day 330 was -33.3% (-59.2% to -7.3%). Six of 9 (66.7%) inclisiran-treated patients (versus 1 of 4 [25%] on placebo) achieved a >15% reduction in LDL-C, and 5 of 9 (55.6%) inclisiran-treated patients (versus none on placebo) achieved a >20% reduction. The placebo-adjusted mean (95% CI) percentage change in PCSK9 from baseline to day 330 was -60.2% (-79.8% to -40.7%); corresponding changes in apoB (apolipoprotein B), non-high-density lipoprotein cholesterol, and total cholesterol were -23.0%, -32.7%, and -27.8%, respectively. No serious adverse events, treatment discontinuations because of adverse events, or deaths occurred. No new safety findings were reported.

CONCLUSIONS

In a 1-year randomized controlled study (part 1 of ORION-13), inclisiran was effective in lowering LDL-C in adolescents with HoFH and was well tolerated. These results support inclisiran as a potentially useful addition for the treatment of adolescents with HoFH and a minimum of LDLR residual activity.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT04659863.

Role of Next-Generation Sequencing in Diagnosis of Familial Hypercholesterolemia in Serbia

Objectives: Familial hypercholesterolemia (FH) is an autosomal dominant disorder of lipid metabolism characterized by high levels of low-density lipoprotein (LDL). This study aimed to identify variants in the LDLR, APOB, PCSK9 and LDLRAP1 genes and to identify the genotype-phenotype correlation in Serbian FH patients. Method: This study included a total of 101 patients suspected of having FH based on clinical criteria. Genetic analysis was performed by the next-generation sequencing (NGS) method. Results: An overall mutation detection rate of 43.6% was achieved. Thirteen distinct variants were detected in the LDLR gene (93.2%). The most frequently observed variant was c.858C>A p.(Ser286Arg), which was present in 26% of the LDLR-positive patients. Additional variants were detected in the APOB gene. No pathogenic variants were detected in the PCSK9 or LDLRAP1 genes. Comparing genetically FH-positive and FH-negative patients, statistical significance was observed in terms of age (p < 0.001), total cholesterol (TC) (p < 0.001), low-density-lipoprotein cholesterol (LDL-C) (p < 0.001) and triglyceridemia (p < 0.001). Conclusions: This study represents the first insight into the genetic basis of FH in Serbia. Taking into consideration that variants were detected in more than one gene and that the variants in the LDLR gene were distributed across nearly all exons, the FH diagnostics in Serbia ought to be based on NGS methodology.

Evinacumab for Homozygous Familial Hypercholesterolemia: The Italian Cohort of the ELIPSE HoFH Study

INTRODUCTION

Homozygous familial hypercholesterolemia (HoFH) is a severe rare genetic disorder characterized by elevated plasma low-density lipoprotein (LDL) cholesterol levels. Here, we report data from the Italian cohort of the Evinacumab Lipid Studies in Patients with Homozygous Familial Hypercholesterolemia (ELIPSE HoFH) trial.

METHODS

ELIPSE HoFH was conducted at 30 sites in 11 countries, with 2-10 patients enrolled per country. The study included patients aged ≥ 12 years with LDL cholesterol ≥ 70 mg/dl (1.8 mmol per liter) at screening despite stable maximally tolerated lipid-lowering therapy. Patients were randomly assigned evinacumab (15 mg/kg every 4 weeks) or matching placebo for 24 weeks, with an option for a 24-week open-label extension or follow-up period thereafter. The Italian cohort included seven patients assigned to evinacumab.

RESULTS

Five patients (3 males and 2 females) received evinacumab and were included in this report. Substantial and consistent reductions in LDL cholesterol from baseline levels were observed in all patients at all follow-up time points. Overall, an 84.5% decrease in median (range) LDL cholesterol was observed, from 323 (203-587) mg/dl in 2016 to 50.0 (13-103) mg/dl (P = 0.043) in 2019, with LDL cholesterol levels stable through 2023. Total cholesterol, high-density lipoprotein (HDL) cholesterol, non-HDL cholesterol, and triglycerides decreased markedly over time. Evinacumab was well tolerated, with no treatment-related adverse events reported.

CONCLUSION

Evinacumab substantially lowered LDL cholesterol levels in patients with HoFH regardless of the degree of LDL receptor function, with low levels sustained over 5 years of follow-up.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT03399786 registered 16 January 2018.

Lomitapide modifies high-density lipoprotein function in homozygous familial hypercholesterolaemia

BACKGROUND

Lomitapide reduces plasma low-density lipoprotein cholesterol (LDL-C) and is approved for the treatment of homozygous familial hypercholesterolemia (HoFH). This study aims to determine the effect of lomitapide on HDL and cholesterol efflux in a cohort of patients with HoFH.

PATIENTS AND METHODS

Analysis included plasma samples from 17 HoFH patients enrolled in the lomitapide phase 3 Aegerion clinical study (NCT00730236). Samples taken at baseline (pre-lomitapide) and weeks 56 and 66 (assumed steady-state on lomitapide) were analyzed for HDL-C levels and cholesterol efflux capacity (CEC) pathways via ABCA1, ABCG1, and SR-BI cholesterol uptake.

RESULTS

Treatment with lomitapide is associated with a statistically significant decrease of both LDL-C and apo B when compared to baseline levels, p < 0.01. However, the reduction of Lp(a) appears only at a higher dose when compared to baseline (- 27% against values around -  55% for LDL-C and apo B). HDL-C shows a small 4.2% increase between the baseline and the treatment with a high dosage of lomitapide, while apo A-I displays an opposite small 3% decrease. Total efflux and ABCA1 mediated CEC decreased especially at higher dosage of lomitapide, with marked dose-dependent increase of SR-BI cholesterol uptake (+ 21.4% and + 64.3%, respectively, at a low and high dosages of lomitapide). However, ABCG1 did not change consistently.

CONCLUSIONS

Our report raises the hypothesis that lomitapide promotes lipidation of HDL particles independently of ABCA1 and ABCG1 through a process involving SR-BI pathway. This effect impairs the total efflux process suggesting that lomitapide drives the reverse cholesterol transport through SR-BI receptors in HoFH patients.

Does Genotype Affect the Efficacy of PCSK9 Inhibitors in the Treatment of Familial Hypercholesterolemia?

PURPOSE OF REVIEW

This review discusses whether patients' genotype affects the efficacy of PCSK9 inhibitors in treating familial hypercholesterolemia and how this might influence clinical management.

RECENT FINDINGS

Currently, available evidence consistently demonstrates and is in good agreement that, in general, the LDL-C-lowering effect of PCSK9 inhibitors is similar across genotypes, except for compound heterozygous and homozygous familial hypercholesterolemia (FH). However, it remains to be seen whether the comparable therapeutic effect in lowering LDL-C level also leads to a comparable degree of cardiovascular risk reduction with different genotypes. Generally, the level of LDL-C reduction following PCSK9 inhibitor treatment is similar within different genotypes. Hence, genotype is a less reliable predictor for further LDL-C level reduction on PCSK9 inhibitor therapy, and attention should be given to other external influences, especially for heterozygous FH.

Ages at coronary heart disease and death in familial hypercholesterolaemia: a Danish nationwide study spanning 44 years

BACKGROUND AND AIMS

Familial hypercholesterolaemia leads to lifelong elevated low-density lipoprotein cholesterol with increased risk of coronary heart disease and pre-mature death. It is unknown whether the prognosis for individuals with familial hypercholesterolaemia has improved over the past four decades as registration of this condition has been limited worldwide. However, in Danish nationwide registries, modified ICD coding has allowed such registration since 1978. This study tested the hypothesis that age at death and coronary heart disease has improved from 1978 to 2021 in individuals with vs. those without familial hypercholesterolaemia.

METHODS

From nationwide registries, all Danish residents were included in a retrospective cohort study. Inclusion and follow-up were from 1978 to 2021. Individuals diagnosed with familial hypercholesterolaemia were identified, and trends over time were examined for age at death and age at coronary heart disease.

RESULTS

During follow-up for those with (n = 10 199) and without (n = 9 174 926) familial hypercholesterolaemia, 27% and 27% died and 34% and 9% experienced coronary heart disease. Age at death was 22 years younger in 1978 (P < .001) but similar in 2021 (P = .16) in individuals with vs. without familial hypercholesterolaemia. Although the corresponding age at coronary heart disease was 20 years younger in 1978 (P < .001), it was still 7 years younger in 2021 (P < .001) in individuals with vs. without familial hypercholesterolaemia. These results were similar in women and men and in a 1:100 matched analysis by sex, ethnicity, and time of birth.

CONCLUSIONS

Nationwide from 1978 to 2021 in Denmark, normalization of age at death but not age at coronary heart disease was observed for individuals diagnosed with familial hypercholesterolaemia.

Population Pharmacokinetics and Exposure-Response Modeling for Evinacumab in Children, Adolescents, and Adults With Homozygous Familial Hypercholesterolemia

Evinacumab, an angiopoietin-like 3 (ANGPTL3) inhibitor, significantly reduces low-density lipoprotein cholesterol (LDL-C), independent of low-density lipoprotein receptor, in patients with homozygous familial hypercholesterolemia (HoFH). A population pharmacokinetic (PK)/pharmacodynamic (PD) model was previously developed to characterize evinacumab exposure and LDL-C response in adolescents and adults. In this analysis, the PK/PD model was refined to include children aged 5 to < 12 years and to characterize the lipoprotein apheresis effect on LDL-C reduction. The PK of evinacumab was characterized by a two-compartment model with parallel linear and non-linear elimination. Linear disposition parameters were allometrically scaled by body weight. Baseline ANGPTL3 concentrations and disease status (non-HoFH vs. HoFH) influenced the maximum target-mediated rate of elimination but had a minimal effect on evinacumab exposures at 15 mg/kg intravenous doses every 4 weeks across weight/age groups. In patients with HoFH, the LDL-C reduction was adequately described by an indirect response model in which evinacumab inhibits the formation of LDL-C and that includes a secondary elimination process quantifying the lipoprotein apheresis effect. Older age was associated with a decrease in baseline LDL-C. An increase in body weight was associated with a reduction in the maximum inhibitory effect of evinacumab. Model-based simulations showed that while evinacumab exposure is reduced with decreasing age/body weight, younger patients are predicted to have a comparable or greater magnitude of LDL-C reduction than older patients at a dose of 15 mg/kg. Overall, the model adequately predicted the evinacumab exposure and LDL-C reduction in children, adolescents, and adults with HoFH, aligning with clinically relevant observations.

Comparison of Model-Predicted and Observed Evinacumab Pharmacokinetics and Efficacy in Children Aged < 5 Years With Homozygous Familial Hypercholesterolemia

Evinacumab, an angiopoietin-like 3 inhibitor, significantly reduces low-density lipoprotein cholesterol (LDL-C) in patients with homozygous familial hypercholesterolemia (HoFH). Herein, we report pharmacokinetic and efficacy analyses of evinacumab in < 5-year-old patients with HoFH. Population pharmacometric models characterizing evinacumab exposure and LDL-C response accounting for lipoprotein apheresis effect in ≥ 5-year-old patients were adapted for growth and maturation to predict and compare evinacumab and LDL-C concentrations across age/weight groups in virtual ≥ 6-month-old patients receiving 15 mg/kg evinacumab intravenous (iv) infusions every 4 weeks (q4w). As expected from allometric theory, weight-based dosing resulted in decreasing evinacumab exposures with declining body weight. Consistent with trends observed in > 5-year-old patients, the predicted percent change from LDL-C baseline (%∆LDL-C) was generally comparable or even higher in < 5-year-old patients (63.0%-68.5%) than in 5- to < 18-year-old patients (61.3%-67.8%) or adults (51.7%), with the predicted percentages of patients achieving %∆LDL-C > 50% also higher in < 5-year-old patients (82.0%-86.9%) versus 5- to < 18-year-old patients (72.0%-84.5%) and adults (54.8%). Through a managed access program, six 1- to < 5-year-old patients received between 5 and 23 iv infusions of 15 mg/kg evinacumab q4w. Rapid and clinically meaningful LDL-C reductions were observed, with %∆LDL-C at the last reported dose ranging from 41.3% to 77.3%. Based on the actual patient dosing and plasmapheresis history, model-predicted evinacumab and LDL-C concentrations were comparable to the observed data collected in the managed access program. Overall, this analysis provides evidence for the use of evinacumab 15 mg/kg iv q4w dosing regimen in 6-month-old to 5-year-old patients.

Prevalence of Familial Hypercholesterolemia in Pakistan: A Pooled Analysis of 1.5 Million Individuals and Comparison with Other Countries of the Region

Background

Familial hypercholesterolemia (FH) is an inherited disorder that causes elevated LDL-C levels leading to premature cardiovascular disease but remains underdiagnosed. This study aims to determine the prevalence of FH in Pakistan using data from multiple laboratory networks and compare it with other counties of the region.

Methods

The study analyzed lipid profile data from two large laboratory networks in Pakistan, applying Make Early Diagnosis to Prevent Early Death (MEDPED) LDL-C criteria for the general population to identify FH cases. A pooled prevalence estimate of prevalence of FH in Pakistan was calculated by combining the data of studies reporting prevalence in Pakistan. A systematic review was conducted to assess FH prevalence in South and Southeast Asian countries.

Results

Analysis of 545,087 individuals (Median age 45 years, 58.2% males) identified 2,911 FH cases [0.55%, 95% confidence interval (CI): 0.53-0.57%), equivalent to a prevalence of 1:182. Pooled analysis with a previous Pakistani study, totaling 1,533,393 subjects, estimated the overall FH prevalence in Pakistan at 1:273 (95% CI: 0.21-0.64%). Prevalence decreased with age, being highest in the <20 years group (1:29), while no gender differences were observed. A systematic review of South and Southeast Asian countries revealed limited data, with FH prevalence estimates missing for majority of the countries of the region.

Conclusion

This study provides an updated estimate of FH prevalence in Pakistan and highlights the scarcity of data in South and Southeast Asia.

High burden of disease in patients with homozygous familial hypercholesterolemia despite recent advances in therapies and updated guidelines: A real-world study

BACKGROUND

Homozygous familial hypercholesterolemia (HoFH) is an ultra-rare disorder of lipid metabolism characterized by markedly increased levels of low-density lipoprotein cholesterol (LDL-C), leading to an increased risk of early onset atherosclerotic cardiovascular disease (ASCVD) and premature death.

OBJECTIVE

To assess the real-world burden of disease for patients with HoFH using healthcare claims data.

METHODS

Due to the lack of International Classification of Diseases, Tenth Revision diagnosis codes for HoFH, the real-world HoFH cohort was formed using 2 sources: prescription claims for evinacumab or lomitapide in the Komodo Healthcare Map™ database; and patients with a physician-confirmed HoFH diagnosis in MyRAREⓇ, a US-based patient support program for commercially available evinacumab. Patients in MyRARE were identified via tokenization and linked with their Komodo claims data.

RESULTS

The real-world cohort comprised 331 patients with HoFH. Mean age was 53.3 years, and 66.8% had a formal diagnosis of familial hypercholesterolemia. Most patients (67.4%) had ASCVD, including 63.4% with coronary heart disease. The most recent mean LDL-C value was 163 mg/dL, and 52.9% of patients had been treated with at least 2 concomitant lipid-lowering therapies.

CONCLUSION

This real-world study showed that patients with HoFH are undertreated, resulting in suboptimal control of LDL-C levels and a high prevalence of ASCVD.

Familial hypercholesterolaemia with high triglycerides: A diagnostic challenge

Combined or mixed hyperlipidaemia is characterised by hypercholesterolaemia together with high triglyceride concentrations. It is found in approximately 1 in 100 people in the United Kingdom. Most cases are secondary to an underlying condition such as the metabolic syndrome, diabetes mellitus (especially poorly controlled) or individuals with a high alcohol intake. Mixed hyperlipidaemia is also a feature of some primary hyperlipidaemia conditions such familial combined hyperlipidaemia (FCH) or type III hyperlipidaemia (dysbetalipoproteinaemia). One differential diagnosis for mixed hyperlipidaemia that can easily be overlooked is a patient with an underlying diagnosis of familial hypercholesterolaemia (FH) who also has a hypertriglyceridaemia due to any other cause. Those patients may have very high total and low-density lipoprotein cholesterol concentrations (LDL-C) with a moderately elevated triglyceride concentration. In this article, we report 4 cases of familial hypercholesterolaemia, confirmed by genetic testing, in patients initially presenting with hypertriglyceridaemia in addition to high total cholesterol and LDL-C. This article discusses the diagnostic challenges associated with this presentation and highlights the key role of directly measuring LDL-C to aid diagnosis in these specific situations.

A strategy to increase identification of patients with Familial Hypercholesterolemia: Application of the Simon Broome lipid criteria in a large-scale retrospective analysis

Introduction

Familial Hypercholesterolemia (FH) is a primarily autosomal dominant condition characterized by markedly elevated low-density lipoprotein-cholesterol (LDL-c) and an increased risk of atherosclerosis and cardiovascular disease (CVD). Though early identification and treatment are crucial to optimizing outcomes, few laboratory strategies exist to detect FH.

Methods

All lipid tests for total cholesterol (TC) and LDL-c ordered through a large nation-wide network of medical laboratories in the United States (US) from 2018 - 2022 were retrospectively evaluated using a decision tree algorithm based on Simon Broome lipid criteria. If thresholds were met, results were classified as "possible FH" or as "no lipid evidence of FH" if not met.

Results

The review of 121,141,307 lipid panels and associated genetic tests from 58,400,105 patients resulted in 1,843,966 (3.2 %) that were classified as "possible FH". Overall, the mean TC was higher in females than males, particularly in those ≥16 years. LDL-c in the "no lipid evidence of FH" cohort increased year-over-year; LDL-c was stable or decreased in the "possible FH" cohort. Despite the large number of patients classified with "possible FH", very few (0.02 %) matched patients had genetic testing.

Conclusion

A laboratory-developed algorithm using Simon Broome lipid criteria can help identify patients who may benefit from additional FH evaluation. While critical, testing hyperlipidemic children for FH is grossly underutilized, as is genetic testing for FH. Diagnostic laboratories are uniquely positioned to bring FH to the attention of clinicians, with the goal of earlier diagnosis, cascade testing, and appropriate treatment.

Evinacumab for the treatment of homozygous familial hypercholesterolaemia: first patient case report in Switzerland

We present the first case in Switzerland of a patient with homozygous familial hypercholesterolaemia treated with evinacumab, a new recombinant human monoclonal antibody currently approved in Europe and in the USA but not yet in Switzerland. Homozygous familial hypercholesterolaemia is a rare genetic disorder that causes severely elevated levels of low-density lipoprotein (LDL) cholesterol and early atherosclerotic cardiovascular disease, which, if left untreated, can lead to premature death. As a result of this newly introduced treatment, the patient's LDL cholesterol levels were reduced by more than half, achieving recommended target values of secondary prevention for the first time. This case underscores the efficacy of evinacumab in achieving LDL cholesterol targets in homozygous familial hypercholesterolaemia patients and highlights the importance of early identification and treatment initiation.

Safety and effectiveness of evinacumab in an infant with homozygous familial hypercholesterolemia: A new renaissance for the very young?

The rare homozygous form of familial hypercholesterolemia (HoFH) is characterized by extremely high low-density lipoprotein (LDL) cholesterol levels, typically exceeding 13 mmol/L (500 mg/dL), and a variable phenotype that may include marked premature atherosclerotic cardiovascular disease. HoFH with null-null LDL receptor mutations can be highly resistant to standard pharmacological therapies. The standard of care treatment option is lipoprotein apheresis (LA). However, LA is not commonly available, is technically demanding, and is relatively invasive and arduous for very young patients. Here we report effective lowering of the LDLcholesterol in a 13-month-old child with HoFH treated with evinacumab, initially at a low dose (7.5 mg/kg), later increased to 15 mg/kg/28 days. The decision was made after the failure of standard drug therapies in a sibling with the same null-null mutation in the LDL receptor, submitted to liver transplantation, who had severe complications. The treatment with evinacumab was safe and effective; LDL cholesterol, triglycerides, and apolipoprotein B concentrations all decreased by over 80%. Our findings suggest that evinacumab is a safe and effective option for treating very young patients with HoFH who do not respond to conventional therapies.

Improving cholesterol management in high-risk primary prevention patients: An evidence-based case series

The National Lipid Association (NLA) is currently conducting a study to improve the uptake of evidence-based guidelines into clinical practice through the deployment of case-based online learning modules to participating health systems nationwide. The Translating Evidence-based Approaches into optimal Care of High-risk atherosclerotic cardiovascular disease patients (TEACH-ASCVD) will evaluate the impact of electronic learning modules on clinician practices related to ASCVD management. In the design phase of TEACH-ASCVD, expert lipidologists created a series of 7 cases informed by recent guidelines intended to provide common clinical scenarios that evaluate participant knowledge of evidence-based practices for high-risk ASCVD and familial hypercholesterolemia. In this manuscript, we present 4 primary prevention-focused cases in high-risk patients and discuss pertinent clinical teaching points. These cases are intended for individuals with clinical lipidology training. We encourage lipidologists to disseminate this manuscript and utilize these cases as a teaching tool for nonlipid specialists to hone their knowledge of common clinical ASCVD risk management scenarios.

Coronary Artery Calcium Is Independently Associated with Arterial Stiffness and LDL Cholesterol Burden in Patients with Familial Hypercholesterolemia

Background: Familial hypercholesterolemia (FH) is a genetic disorder characterized by high plasma levels of low-density lipoprotein cholesterol (LDL-C) and exposing patients to higher risk of early cardiovascular (CV) atherosclerotic diseases. Though the estimated prevalence of heterozygous FH (HeFH) is about 1 in 200, FH is still underdiagnosed and undertreated. Coronary artery calcification (CAC) assessment and arterial stiffness measured as pulse wave velocity (PWV) have demonstrated their accuracy in CV risk assessment, but data on HeFH are lacking. This study aims to evaluate CAC and PWV in a population of HeFH patients to improve risk stratification and therapy timing and setting. Methods: One hundred genetically characterized HeFH patients, regularly followed up since diagnosis, were recruited at our outpatient clinic. In all patients, CAC, PWV measurement, and LDL-C burden calculation were assessed. Results: The mean age was 45 ± 16 years. A total of 25% of patients had hypertension, and 15% were in secondary prevention. Through univariate analysis, we found strong positive correlations between CAC and both PWV (r = 0.52 p > 0.0001) and total LDL-C burden (r = 0.52 p < 0.0001). No other associations with lipid parameters were found. Multivariate analysis showed that CAC was independently associated with PWV adjusted for sex, total LDL-C burden, systolic blood pressure, smoking, LDL-C, HDL-C, and statin treatment. Conclusions: Arterial stiffness is strongly associated with CAC in HeFH patients with similar total LDL-C burden and CV risk profiles. Personalized risk assessment based on arterial stiffness and CAC evaluation enhances the stratification and management of cardiovascular risk in FH patients, supporting individualized therapeutic approaches.

Resistance to conventional drug therapy and good response to lomitapide allowed the identification of a novel bi-allelic semi-dominant monogenic HoFH: a case report

INTRODUCTION

Familial hypercholesterolaemia (FH) is a genetic disorder associated with high cholesterol levels and an increased risk of premature cardiovascular events. Rare forms, such as semi-dominant bi-allelic mutations, pose diagnostic and therapeutic challenges. Misdiagnosis of FH is a significant concern, as highlighted by both this case and a review of the literature.

CASE REPORT

We report the case of a 54-year-old woman with an acute myocardial infarction at the age of 43 years. She had a positive family history of early cardiovascular events and was diagnosed with familial hypercholesterolaemia at the age of 33 years. She tried statins with no benefit. In 2017, evolocumab was introduced but was insufficient to control cholesterol values (low-density lipoprotein cholesterol 324 mg/dL). She started lomitapide, and next-generation sequencing screening was performed in consideration of the different pharmacological effects and clinical trends compared to other family members. A bi-allelic semi-dominant mutation (c.241C > T in exon 3 of the LDLR gene) was found in addition to the previously identified mutation. She is now in good clinical condition and laboratory response with lomitapide, evolocumab, statin, and ezetimibe. A literature review was conducted to explore the clinical and diagnostic challenges of FH, with a focus on the risk of misdiagnosis.

CONCLUSION

This case underscores the importance of genetic testing in diagnosing rare forms of FH, such as semi-dominant bi-allelic mutations, which may lead to misdiagnosis. Lomitapide proved effective in controlling cholesterol levels, highlighting its value in managing complex FH cases. The literature review further emphasizes the critical need for improved diagnostic approaches to minimize the risk of misdiagnosis.

Liver transplantation for homozygous familial hypercholesterolemia: a retrospective analysis from Chinese experience

BACKGROUND

Homozygous familial hypercholesterolaemia (HoFH) increases risk of premature cardiovascular events and cardiac death. In severe cases of HoFH, clinical signs and symptoms cannot be controlled well by non-surgical treatments, liver transplantation (LT) currently represents the viable option.

METHOD

To assess the clinical efficacy, prognosis, and optimal timing of LT for HoFH, a retrospective analysis was conducted on the preoperative, surgical conditions, and postoperative follow-up of children who received an LT for HoFH at the Beijing Friendship Hospital over the period from December 2014 to August 2022.

RESULTS

Xanthoma and decreased activity tolerance were the primary clinical manifestations in the 7 HoFH children initially assessed (one child died suddenly prior to surgery due to cardiac arrest). Accompanying these symptoms were increased blood total cholesterol (TC) and low density lipoprotein (LDL) levels, along with severe cardiovascular diseases. HoFH was confirmed in all cases by genetic and biochemical assays. Initial treatments administered to these patients consisted of low-fat diets and lipid-lowering drugs with poor outcomes. Accordingly, all 6 patients received orthotopic liver transplantations (OLT), with the result that significant postoperative reductions were observed in levels of TC and LDL. The median follow-up of these six cases was 37.41 months (range: 19.40-94.10 months). Regular postoperative follow-ups revealed that all survived and showed significant improvements in their clinical symptoms.

CONCLUSION

So far, LT is the only way to heal HoFH. LT before the appearance of obvious cardiovascular atherosclerotic lesions can significantly improve the quality of life and prognosis of patients. At the same time, the blood cholesterol level of patients should be continuously monitored after LT to further control the progression of vascular complications.

ApoB100 remodeling and stiffened cholesteryl ester core raise LDL aggregation in familial hypercholesterolemia patients

Patients with familial hypercholesterolemia (FH) exhibit a significant residual cardiovascular risk. A new cardiovascular risk factor is the susceptibility of individual LDL particles to aggregation. This study examined LDL aggregation and its relationship with LDL lipid composition and biophysical properties in patients with FH compared to controls. LDL aggregation was measured as the change in particle size, assessed by dynamic light scattering, after exposure to sphingomyelinase, which breaks down sphingomyelin in the LDL phospholipid layer. Dynamic light scattering and transmission electron microscopy showed that LDL in FH patients exhibited smaller size and greater susceptibility to aggregation. Biochemical analyses revealed a higher cholesteryl ester (CE)/ApoB100 ratio in LDL from FH patients. Differential scanning calorimetry showed that LDL from FH patients had higher transition temperatures, indicating a more ordered CE core. Fourier transform infrared spectroscopy revealed fewer flexible α-helices (1658 cm⁻1) and more stable α-helices (1651 cm⁻1) in ApoB100 of LDL from FH patients. These structural changes correlated with higher CE content and increased LDL aggregation. In conclusion, a more ordered CE core in smaller LDL particles, combined with a higher proportion of stable α-helices in ApoB100, promotes LDL aggregation in FH patients. These findings suggest ApoB100 conformational structure as a new potential therapeutic targets within LDL to reduce cardiovascular risk in FH patients.

Familial hypercholesterolemia in Chinese children and adolescents: a multicenter study

BACKGROUND

Familial hypercholesterolemia (FH) is an inherited disorder mainly marked by increased low-density lipoprotein cholesterol (LDL-C) concentrations and a heightened risk of early-onset arteriosclerotic cardiovascular disease (ASCVD). This study seeks to characterize the genetic spectrum and genotype‒phenotype correlations of FH in Chinese pediatric individuals.

METHODS

Data were gathered from individuals diagnosed with FH either clinically or genetically at multiple hospitals across mainland China from January 2016 to June 2024.

RESULTS

In total, 140 children and adolescents (mean age of 6.00 years) with clinically and genetically diagnosed FH were enrolled in the study, with 87 distinct variants identified in the LDLR, APOB and PCSK9 genes. Among the variants, 11 variants were newly identified worldwide, with 9 classified as "pathogenic" or "likely pathogenic", and 2 classified as "variants of uncertain significance". Additionally, the 5 most common variants in the study were c.1448G > A (p.W483*), c.1879G > A (p.A627T), c.1216C > A (p.R406R), and c.1747C > T (p.H583Y) in the LDLR gene, as well as c.10579C > T (p.R3527W) in the APOB gene, accounting for 49.29% (69/140) of all patients. These variants are primarily observed in the Asian or Chinese population and are distinct from those present in Caucasian groups. In this cohort, 105 patients were diagnosed with heterozygous FH (HeFH), while 35 were diagnosed with homozygous FH (HoFH). Finally, only 28.57% of the patients (40/140) were using lipid-lowering medications with 33.33% of HoFH patients initiating treatment after the age of 8. Additionally, only 3 compound heterozygous patients (2.14%) underwent liver transplantation because of significantly high lipid levels.

CONCLUSION

This study reveals the variable genotypes and phenotypes of children with FH in China and illustrates that the genotypes in the Chinese population differ from those in Caucasians, providing a valuable dataset for the clinical genetic screening of FH in China. Furthermore, the older age at diagnosis and treatment highlights the underdiagnosis and undertreatment of Chinese FH pediatric patients, suggesting that early identification should be improved through lipid or genetic screening, and that more timely and regular pharmacological treatments should be implemented.

New insights into the management of homozygous familial hypercholesterolemia patients treated with lomitapide: a single-center experience

Familial hypercholesterolemia (FH) is a genetic disease, usually with onset during childhood, characterized by elevated blood LDL cholesterol levels and potentially associated with severe cardiovascular complications. Concerning mutated genes in FH, such as LDLR, a small subset of FH patients presents a homozygous genotype, resulting in homozygous FH (HoFH) disease with a generally aggressive phenotype. Besides statins, ezetimibe and PCSK9 inhibitors, lomitapide (an anti-ApoB therapy) was also approved in 2012-2013 as an adjunctive treatment for HoFH. Despite its clinical efficacy, lomitapide administration should be done with caution because of the possible occurrence of side effects, such as hepatosteatosis, increased blood transaminase levels and gastrointestinal symptoms, as well as the possible deleterious interactions with other drugs. In this context, we decided to report the main available evidence on the management and monitoring of HoFH patients treated with lomitapide and to accompany this literature review with a description of our clinical experience with a subset of six HoFH patients. In conclusion, this paper aims to address an important topic for HoFH-related clinical practice that, to our knowledge, is not yet formally regulated by proper national and/or international guidelines.

Improved Genetic Characterization of Hypercholesterolemia in Latvian Patients with Familial Hypercholesterolemia: A Combined Monogenic and Polygenic Approach Using Whole-Genome Sequencing

Despite the implementation of next-generation sequencing-based genetic testing on patients with clinical familial hypercholesterolemia (FH), most cases lack complete genetic characterization. We aim to investigate the utility of the polygenic risk score (PRS) in specifying the genetic background of patients from the Latvian Registry of FH (LRFH). We analyzed the whole-genome sequencing (WGS) data of the clinically diagnosed FH patients (n = 339) and controls selected from the Latvian reference population (n = 515). Variant pathogenicity in FH patients was classified according to the ACMG/AMP guidelines. The low-density lipoprotein cholesterol (LDL-C) and lipoprotein (a) (LPA) PRS were calculated based on the WGS data. We identified unique causative variants in 80 (23.6%) of the tested individuals (39 variants in FH genes and 4 variants in phenocopy genes, with 6 variants being novel). The LDL-C PRS was highly discriminative compared to the LPA PRS. Nevertheless, both PRS were able to explain the genetic cause of hypercholesterolemia in 26.3% of the remaining non-monogenic patients. The combined genetic analysis of monogenic and polygenic hypercholesterolemia resulted in 43.7% genetically explained hypercholesterolemia cases. Even though the application of PRS alone does not exclude monogenic testing in clinical FH patients, it is a valuable tool for diagnosis specification.

Lomitapide for the treatment of paediatric patients with homozygous familial hypercholesterolaemia (APH-19): results from the efficacy phase of an open-label, multicentre, phase 3 study

BACKGROUND

Homozygous familial hypercholesterolaemia (HoFH) is a rare inherited disorder characterised by extremely high concentrations of LDL cholesterol, leading to early-onset atherosclerosis. Lomitapide is an orally administered microsomal triglyceride transfer protein (MTP) inhibitor that effectively lowers LDL cholesterol and is approved for adults with HoFH. We aimed to investigate the efficacy and safety of lomitapide in paediatric patients with HoFH receiving standard-of-care lipid-lowering therapy.

METHODS

APH-19 is an open-label, single-arm, phase 3 trial performed at 12 study centres in Germany, Israel, Italy, Saudi Arabia, Spain, and Tunisia. A 6-week run-in period was followed by a 24-week efficacy phase and an 80-week safety phase. Patients aged 5-17 years, on stable lipid-lowering therapy, with HoFH diagnosed using the criteria from the 2014 European Atherosclerosis Society Consensus Panel on HoFH were titrated to maximum tolerated doses of oral lomitapide, starting at 2 mg (patients aged 5-15 years) or 5 mg (patients aged 16-17 years). The primary endpoint was the percentage change from baseline to week 24 in LDL cholesterol, which was assessed in patients who had received at least one dose of lomitapide, and who had a baseline and at least one post-baseline measurement. The secondary outcomes were the percentage change from baseline at week 24 in total cholesterol, non-HDL cholesterol, VLDL cholesterol, apolipoprotein B, triglycerides, and lipoprotein(a). Safety was assessed in patients who received at least one dose of study drug. This study is registered with ClinicalTrials.gov, NCT04681170.

FINDINGS

Between Dec 20, 2020, and Oct 16, 2022, 43 patients were included and treated (24 [56%] were female and 19 [44%] were male, and median age was 10·7 years [7·0-14·0]). Mean change from baseline in LDL cholesterol at week 24 was -53·5% (95% CI -61·6 to -45·4, p<0·0001). Mean percentage reductions were observed at week 24 for non-HDL cholesterol (-53·9%, 95% CI -61·7 to -46·1, p<0·0001), total cholesterol (-50·0%, 95% CI -57·6 to -42·4, p<0·0001), VLDL cholesterol (-50·2%, -59·1 to -41·2, p<0·0001), apolipoprotein B (-52·4%, -60·3 to -44·5, p<0·0001), triglycerides was -49·9% (-58·8 to -41·0, p<0·0001), and lipoprotein(a) (-11·3%, -32·9 to 10·3 [in 21 patients with measurements in mg/dL]; -23·6%, -38·2 to -9·0 [in 22 patients with measurements in nmol/L]; p=0·0070 combined). Adverse events were mostly mild, and gastrointestinal and hepatic in nature. Adverse events of special interest were reported for five (12%) patients (gastrointestinal in two patients and hepatic in three). One serious treatment-emergent adverse event was reported (also classed as an adverse event of special interest): an increase in hepatic enzymes, resulting in two dose interruptions, two dose reductions, and a repeated dose escalation.

INTERPRETATION

Lomitapide provided a significant, clinically meaningful LDL cholesterol reduction and has the potential to be an efficient, LDL receptor-independent option for paediatric patients with HoFH.

FUNDING

Amryt Pharmaceuticals.

Current treatments for the management of homozygous familial hypercholesterolaemia: a systematic review and commentary

AIMS

Homozygous familial hypercholesterolaemia (HoFH) is a rare disorder characterized by markedly elevated circulating low-density lipoprotein cholesterol (LDL-C) from birth. This review aimed to critically evaluate treatments for HoFH with respect to their efficacy, safety, accessibility, overall context and position within the treatment pathway.

METHODS AND RESULTS

A mixed-methods review was undertaken to systematically identify and characterize primary interventional studies on HoFH, with a focus on LDL-C reduction as the primary outcome. Interventions assessed were ezetimibe, proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i), lomitapide, evinacumab, with or without LDL apheresis. Twenty-six seminal studies reporting unique patient data were identified. Four studies were randomized controlled trials (RCTs) with the remainder being single-arm trials or observational registries. Data extracted were heterogeneous and not suitable for meta-analyses. Two RCTs, assessed at being low risk of bias, demonstrated PCSK9i were safe and moderately effective. A randomized controlled trial (RCT) demonstrated evinacumab was safe and effective in all HoFH subgroups. Lomitapide was reported to be efficacious in a single-arm trial, but issues with adverse events, tolerability, and adherence were identified. An RCT on ezetimibe showed it was moderately effective when combined with a statin. LDL apheresis was reported as effective, but its evidence base was at very high risk of bias. All interventions lowered LDL-C, but the magnitude of this, and certainty in the supporting evidence, varied.

CONCLUSION

In practice, multiple treatments are required to treat HoFH. The sequencing of these should be made on an individualized basis, with consideration made to the benefits of each intervention.

Targeted NGS Revealed Pathogenic Mutation in a 13-Year-Old Patient with Homozygous Familial Hypercholesterolemia: A Case Report

Familial hypercholesterolemia is an autosomal hereditary disease defined by an increased level of low-density lipoprotein cholesterol (LDL-C), which predisposes significant risks for premature cardiovascular disorders. We present a family trio study: proband, a 13-year-old Kazakh girl with homozygous familial hypercholesterolemia (HoFH) and her parents. HoFH is much more rare and severe than a heterozygous form of the disorder. HoFH patients generally present with LDL-C levels exceeding 13 mmol/L, resulting in early and life-threatening cardiovascular events within the first decades of life. In cases of neglected treatment, young patients have a risk of death from coronary diseases before the age of 30. The aim of this research was to identify genetic mutations in the affected patient and her parents. Genetic testing was necessary due to highly elevated LDL-C levels and the presence of multiple xanthomas. Targeted next-generation sequencing (NGS) was performed in this study using the Illumina TruSight cardio panel, which targets 174 genes related to cardiac disorders. The girl was diagnosed with HoFH based on the results of genetic testing. A biallelic mutation was observed in exon 3 of the low-density lipoprotein receptor (LDLR): c. 295 G>A (p.Glu99Lys). Sanger sequencing confirmed that the mutant gene was inherited from both parents. After confirming the genetic diagnosis of HoFH, the patient was treated with LDL apheresis and statins. This case report is the first study of HoFH in a pediatric patient from the Central Asian region. Globally, it emphasizes the need for increased clinical awareness among healthcare providers, as early detection and intervention are important for improving outcomes, particularly in pediatric patients with this rare genetic disorder.

The therapeutic effect of liver transplantation in 14 children with homozygous familial hypercholesterolemia: A prospective cohort: Liver transplant for familial hypercholesterolemia

OBJECTIVES

Homozygous familial hypercholesterolemia (HoFH) is characterized by elevated low-density lipoprotein cholesterol (LDL-C) and early-onset cardiovascular disease. To assess the therapeutic effects of liver transplantation (LT) on HoFH patients, we observed and analyzed the outcomes of HoFH children after LT.

STUDY DESIGN

This prospective cohort study included all LT candidates under 18 years old diagnosed with HoFH at Ren Ji Hospital between November 2017 and July 2021. The patients were followed until October 2023. They were treated according to the standard protocol at our center. We collected data on changes in lipid profiles, clinical manifestations, and cardiovascular complications at different time points, and recorded postoperative recipient and graft survival.

RESULTS

Fourteen HoFH patients with a median age of 7 (2-12) years were included. Preoperatively, xanthomas and arcus corneas occurred in 14 and 3 patients, respectively, with 10 patients showing mild cardiovascular disease. All patients underwent LT. Recipient and graft survival rates were 100% over a median follow-up duration of 35 (27-71) months. Median LDL-C levels dropped from 11.83 (7.99-26.14) mmol/L preoperatively to 2.3 (1.49-3.39) mmol/L postoperative at the last measurement. Thirteen patients discontinued lipid-lowering treatment after LT, while only one patient resumed statins 6 months post-operation. Xanthomas and arcus corneas significantly improved. Cardiovascular complications regressed in five patients, with no progression observed in the others.

CONCLUSIONS

LT is a safe and effective treatment for severe HoFH patients beyond lipid-lowering control. Early LT improves prognosis and quality of life while minimizing the risk of cardiovascular complications.

Targeting LDL aggregation decreases atherosclerotic lipid burden in a humanized mouse model of familial hypercholesterolemia: Crucial role of ApoB100 conformational stabilization

BACKGROUND AND AIMS

Low-density lipoprotein (LDL) aggregation is nowadays considered a therapeutic target in atherosclerosis. DP3, the retro-enantio version of the sequence Gly1127-Cys1140 of LRP1, efficiently inhibits LDL aggregation and foam cell in vitro formation. Here, we investigate whether DP3 modulates atherosclerosis in a humanized ApoB100, LDL receptor (LDLR) knockout mice (Ldlr-/-hApoB100 Tg) and determine the potential LDL-related underlying mechanisms.

METHODS

Tg mice were fed an HFD for 21 days to induce atherosclerosis and then randomized into three groups that received a daily subcutaneous administration (10 mg/kg) of i) vehicle, ii) DP3 peptide, or iii) a non-active peptide (IP321). The in vivo biodistribution of a fluorescent-labeled peptide version (TAMRA-DP3), and its colocalization with ApoB100 in the arterial intima, was analyzed by imaging system (IVIS) and confocal microscopy. Heart aortic roots were used for atherosclerosis detection and quantification. LDL functionality was analyzed by biochemical, biophysical, molecular, and cellular studies.

RESULTS

Intimal neutral lipid accumulation in the aortic root was reduced in the DP3-treated group as compared to control groups. ApoB100 in LDLs from the DP3 group exhibited an increased percentage of α-helix secondary structures and decreased immunoreactivity to anti-ApoB100 antibodies. LDL from DP3-treated mice were protected against passive and sphingomyelinase (SMase)-induced aggregation, although they still experienced SMase-induced sphingomyelin phospholysis. In patients with familial hypercholesterolemia (FH), DP3 efficiently inhibited both SMase-induced phospholysis and aggregation.

CONCLUSIONS

DP3 peptide administration inhibits atherosclerosis by preserving the α-helix secondary structures of ApoB100 in a humanized ApoB100 murine model that mimicks the hallmark of human hypercholesterolemia.

Effect of diet and genotype on the lipidome of mice with altered lipoprotein metabolism

The present study describes and compares the impact of PCSK9 and LDLR, two pivotal players in cholesterol metabolism, on the whole lipidome of plasma, liver and aorta in different dietary conditions. This issue is relevant, since several lipid species, circulating at very low concentrations, have the ability to impair lipid metabolism and promote atherosclerosis development. To this aim, wild-type, hypercholesterolemic Ldlr-KO, and hypocholesterolemic Pcsk9-KO mice were fed a standard chow or a Western-type diet up to 30 and 16 weeks of age, respectively. 42 lipids including cholesterol, cholesteryl esters, several sphingolipids, phospholipids, and lysophospholipids, accumulated uniquely in the atherosclerotic aorta of Western-type diet-fed Ldlr-KO mice. In addition, multiple organ/tissue comparisons allowed us to identify 16 lipids whose plasma and hepatic patterns mirrored the lipidome of the atherosclerotic aorta. These lipid species, belonging to cholesteryl esters, glucosyl/galactosylceramide, lactosylceramide, globotriaosylceramide, sphingomyelin, and phosphatidylcholine could be further investigated as circulating biomarkers or therapeutic targets.

The Lipoprotein Profile Evaluated by 1H-NMR Improves the Performance of Genetic Testing in Familial Hypercholesterolemia

BACKGROUND

The familial hypercholesterolemia (FH) diagnosis is based on clinical and genetic criteria. A relevant proportion of FH patients fulfilling the criteria for definite FH have negative genetic testing. Increasing the identification of true genetic-based FH is a clinical challenge. Deepening the analysis of lipoprotein alterations could help increase the yield of genetic testing. We evaluated whether the number, size, and composition of lipoproteins assessed by 1H-NMR could increase the identification of FH patients with pathogenic gene variants.

METHODS

We studied 294 clinically definite FH patients, 222 (75.5%) with positive genetic testing, as the discovery cohort. As an external validation cohort, we studied 88 children with FH, 72 (81%) with positive genetic testing. The advanced lipoprotein test based on 1H-NMR (Liposcale®) was performed at baseline after a lipid-lowering drug washout of at least 6 weeks. The association of variables with genetic variants was evaluated by random forest and logistic regression. Areas under the curve (AUCs) were calculated. A predictive formula was developed and applied to the validation cohort.

RESULTS

A formula derived from nuclear magnetic resonance (NMR) lipoprotein analyses improved the identification of genetically positive FH patients beyond low-density lipoprotein (LDL)-cholesterol levels (AUC = 0.87). The parameters contributing the most to the identification formula were LDL particle number, high-density lipoprotein size, and remnant cholesterol. The formula also increases the classification of FH children with a pathogenic genetic variation.

CONCLUSION

NMR lipoprotein profile analysis identifies differences beyond standard lipid parameters that help identify FH with a positive pathogenic gene variant, increasing the yield of genetic testing in FH patients.

Long-term effectiveness and safety of lomitapide in patients with homozygous familial hypercholesterolemia: an observational case series

BACKGROUND

We assessed long-term real-world effectiveness and safety of lomitapide in patients with homozygous familial hypercholesterolemia (HoFH).

METHODS

Retrospective case series of six patients with HoFH treated with lomitapide in an Italian clinic. Changes in low-density lipoprotein cholesterol (LDL-C) during lomitapide treatment were assessed. The effect on LDL-C of PCSK9 inhibitors, apheresis and lomitapide was evaluated. Additionally, high-density lipoprotein cholesterol (HDL-C), gastrointestinal tolerability, hepatic steatosis/elasticity, transaminases, and cardiovascular events and symptoms were assessed.

RESULTS

Median age at HoFH clinical and molecular diagnoses was 25 (range 2-49) and 40 (29-71) years, respectively. Five (83.3%) had prior cardiovascular events. One patient received apheresis, which was subsequently discontinued. All patients received PCSK9 inhibitors but discontinued due to minimal effectiveness. Median (range) age at lomitapide initiation was 44 (28-73) years, with a median 47 (18-85) months' treatment (mean dose 17.5 [5-40] mg/day). Mean (SD) baseline LDL-C was 263.2 (148.1) mg/dL, which decreased by 80% at nadir (52.8 [19.2] mg/dL) and 69% at last follow-up (81.3 [30.5] mg/dL). Four patients (66.7%) achieved LDL-C < 70 mg/dL sometime during follow-up, all of whom also achieved LDL-C < 55 mg/dL. Adverse events (AEs) were generally mild to moderate, hepatic steatosis was either absent or mild/moderate and hepatic elasticity remained normal in all but two patients (> 70 years old). All patients with reported cardiovascular symptoms had improvements in symptoms, and all patients reported stabilization or regression of intima-media thickness and atheromatous plaques.

CONCLUSIONS

These long-term, real-world data demonstrate that lomitapide substantially reduced LDL-C for up to seven years. Most patients achieved LDL-C goal at some point, consistent with published Phase III trial and real-world evidence data. No patient discontinued lomitapide treatment. Further long-term follow-up in a larger patient population will be important to determine cardiovascular and other outcomes.

Lipoprotein apheresis: an established therapeutic modality for homozygous familial hypercholesterolemia patients refractory to PCSK9 inhibitors: a case report and literature review

Homozygous familial hypercholesterolemia (HoFH), is a rare genetic disorder characterized by dual mutations in the low-density lipoprotein receptor (LDLR) gene, leading to dysfunctional or absent LDLRs, often accompanied by severe premature Atherosclerotic Cardiovascular Disease (ASCVD) and exhibiting refractoriness to aggressive pharmacological interventions. Double filtration plasmapheresis (DFPP), a form of lipoprotein apheresis (LA), has been effectively utilized as an adjunctive treatment modality to reduce serum LDL-C levels in refractory cases of HoFH. Here, we report a case of a 36-year-old female with HoFH who developed xanthomas on her limbs and waist at age 7. Despite maximum-tolerated doses of statins from age 32, combined with ezetimibe and evolocumab, her LDL-C levels remained critically elevated at 12-14 mmol/L. Her genetic testing confirmed a homozygous LDLR mutation. At 35 years old, she experienced exertional chest pain, and percutaneous coronary intervention revealed severe calcific left main stenosis, necessitating stent implantation. Subsequently, she initiated once every 1-2 months DFPP. Pre-DFPP, her LDL-C and total cholesterol (TC) levels were 13.82 ± 3.28 and 15.45 ± 0.78 mmol/L, respectively. Post-DFPP, her LDL-C and TC levels significantly decreased to 2.43 ± 0.33 mmol/L (81.76 ± 4.11% reduction) and 3.59 ± 0.41 mmol/L (76.76 ± 2.75% reduction), respectively. Lipoprotein (a) and triglycerides also decreased by 89.10 ± 1.39% and 42.29 ± 15.68%,respectively. Two years later, there was no progression of coronary artery disease, and her symptoms and xanthomas regressed significantly. Collectively, DFPP effectively reduces LDL-C levels in refractory cases of HoFH and contributes to delaying ASCVD progression, representing an efficacious adjunctive therapeutic modality.

The LDL cumulative exposure hypothesis: evidence and practical applications

The trapping of LDL and other apolipoprotein B-containing lipoproteins within the artery wall causes atherosclerosis. As more LDL becomes trapped within the artery wall over time, the atherosclerotic plaque burden gradually increases, raising the risk of an acute cardiovascular event. Therefore, the biological effect of LDL on the risk of atherosclerotic cardiovascular disease (ASCVD) depends on both the magnitude and duration of exposure. Maintaining low levels of LDL-cholesterol (LDL-C) over time decreases the number of LDL particles trapped within the artery wall, slows the progression of atherosclerosis and, by delaying the age at which mature atherosclerotic plaques develop, substantially reduces the lifetime risk of ASCVD events. Summing LDL-C measurements over time to calculate cumulative exposure to LDL generates a unique biomarker that captures both the magnitude and duration of exposure, which facilitates the estimation of the absolute risk of having an acute cardiovascular event at any point in time. Titrating LDL-C lowering to keep cumulative exposure to LDL below the threshold at which acute cardiovascular events occur can effectively prevent ASCVD. In this Review, we provide the first comprehensive overview of how the LDL cumulative exposure hypothesis can guide the prevention of ASCVD. We also discuss the benefits of maintaining lower LDL-C levels over time and how this knowledge can be used to inform clinical practice guidelines as well as to design novel primary prevention trials and ASCVD prevention programmes.

Severe multivessel coronary heart disease in a young woman with familial hypercholesterolemia and congenital heart disease: A case report

The prevalence of premature atherosclerotic cardiovascular disease (ASCVD) ranges from 7% to 30%, but the incidence in young patients is increasing. Traditional risk factors, such as hypertension, hyperlipidemia, obesity, and diabetes, have an increasing prevalence in young patients and especially in young women. A 32-year-old woman presented with dyspnea and exertional chest pain. She had a history of familial hypercholesterolemia and unidentified aortic valve disease status after a pulmonary autograft at the age of 20. Due to insurance changes with the onset of the COVID-19 pandemic, she lost access to specialty care. She was not on any cholesterol-lowering agents prior to admission. An electrocardiogram demonstrated no ST changes with elevated high-sensitivity troponin-I concerning for non-ST elevation myocardial infarction. Laboratory data also revealed elevated LDL-C greater than 400. Due to concern for multivessel disease and complex anatomy, she underwent coronary computerized tomography angiography, which verified her multivessel coronary artery disease. An echocardiogram demonstrated a preserved ejection fraction and moderate aortic regurgitation. Her coronary artery bypass graft was deferred due to possible future valvular surgery. She underwent percutaneous coronary intervention with drug-eluting stents to left circumflex and left anterior descending arteries. Familial hypercholesterolemia is a prevalent but under-recognized and under-treated risk factor for premature ASCVD, which can be adequately identified through improved risk assessment and managed with aggressive combination anti-hyperlipidemia therapy.

Lipidomic profiling in patients with familial hypercholesterolemia: Abnormalities in glycerolipids and oxysterols

OBJECTIVES AND AIM

This study aimed to identify precise biomarkers and develop targeted therapeutic strategies for preventing premature atherosclerotic cardiovascular disease in patients with familial hypercholesterolemia (FH) by investigating the quantitative and qualitative abnormalities in the metabolic network of lipids in these patients using an advanced lipidomics platform.

DESIGN & METHODS

The study population comprised 18 homozygous (HoFH), 18 heterozygous (HeFH) FH patients, and 20 healthy controls. Cholesterol oxidation products (oxysterol, COPs) and main lipid classes were determined using gas chromatography-mass spectrometry. Results were expressed as percentages of total fat matter for lipid classes and percentages of total COPs for oxysterols. The principal component analysis (PCA) was also carried out, to highlight the correlation between studied parameters and groups investigated.

RESULTS

Patients (both HoFH and HeFH) showed lower content of free fatty acids (FFAs) and greater values of triacylglycerols (TAGs) in comparison to controls. HoFH showed lower monoacylglycerols (P<0.01) and higher free cholesterol (FC) (P<0.05) when compared to HeFH and controls. The total content of COPs ranged from 1.96 to 4.25 mg/dL, from 2.27 to 4.05 mg/dL, and from 0.79 to 4.12 mg/dL in healthy controls, HoFH and HeFH groups, respectively, with no significant differences between patients and controls. In general, the 7α-hydroxycholesterol (7α-HC) was greater than other COPs. However, no significant differences were found between the three studied groups. Moreover, an opposite trend was observed between 7α-HC and 7-ketocholesterol (7-KC). Additionally, when PCA was carried out, the first two PCs explained 92.13 % of the total variance, of which the PC1 describes 53.94 % of variance mainly correlated to TAGs, diacylglycerols (DAGs), and 7-KC. On the other hand, the PC2 was correlated primarily for FFAs, FC and esterified sterols (E-STE).

CONCLUSIONS

In conclusion, abnormal levels of TAGs, DAGs and 7-KC were associated with HeFH while HoFH was associated with the abnormal amount of E-STE.

Potentials of artificial intelligence in familial hypercholesterolemia: Advances in screening, diagnosis, and risk stratification for early intervention and treatment

Familial hypercholesterolemia (FH) poses a global health challenge due to high incidence rates and underdiagnosis, leading to increased risks of early-onset atherosclerosis and cardiovascular diseases. Early detection and treatment of FH is critical in reducing the risk of cardiovascular events and improving the long-term outcomes and quality of life for affected individuals and their families. Traditional therapeutic approaches revolve around lipid-lowering interventions, yet challenges persist, particularly in accurate and timely diagnosis. The current diagnostic landscape heavily relies on genetic testing of specific LDL-C metabolism genes, often limited to specialized centers. This constraint has led to the adoption of alternative clinical scores for FH diagnosis. However, the rapid advancements in artificial intelligence (AI) and machine learning (ML) present promising solutions to these diagnostic challenges. This review explores the intricacies of FH, highlighting the challenges that are encountered in the diagnosis and management of the disorder. The revolutionary potential of ML, particularly in large-scale population screening, is highlighted. Applications of ML in FH screening, diagnosis, and risk stratification are discussed, showcasing its ability to outperform traditional criteria. However, challenges and ethical considerations, including algorithmic stability, data quality, privacy, and consent issues, are crucial areas that require attention. The review concludes by emphasizing the significant promise of AI and ML in FH management while underscoring the need for ethical and practical vigilance to ensure responsible and effective integration into healthcare practices.

The Importance of Genetic Testing for Familial Hypercholesterolemia: A Pediatric Pilot Study

Background and Objectives: Familial hypercholesterolemia (FH) is a genetic disease that is massively underdiagnosed worldwide. Affected patients are at high risk of cardiovascular events at young ages. Early intervention in childhood could help prevent heart attacks and cerebral strokes in these patients. Materials and Methods: We conducted an interventional study including 10 patients that previously underwent genetic testing for familial hypercholesterolemia. These patients received lifestyle and diet recommendations that they followed for a year before being reevaluated. Results: Patients with negative genetic testing were able to achieve lower levels in their lipid panel values compared to the patients with positive genetic testing, with lifestyle changes alone. LDL-cholesterol levels decreased by 18.5% in patients without FH while patients genetically confirmed with FH failed to achieve lower LDL-cholesterol levels without medication. Conclusions: Genetic testing for FH is not always part of screening algorithms for FH. Some studies even advise against it. Our study proved the importance of genetic testing for FH when suspecting this disorder and choosing the treatment course for patients.

Brazilian Guideline for Exercise Testing in Children and Adolescents - 2024

CLASSES OF RECOMMENDATION

LEVELS OF EVIDENCE

Characteristics, Physiopathology and Management of Dyslipidemias in Pregnancy: A Narrative Review

Dyslipidemia is a significant risk factor for atherosclerotic cardiovascular disease (ASCVD). During pregnancy, physiological changes elevate cholesterol and triglyceride levels to support fetal development, which can exacerbate pre-existing conditions and lead to complications such as pre-eclampsia, gestational diabetes, and increased ASCVD risk for both mother and child. Effective management strategies are necessary, especially for pregnant women with inherited forms of dyslipidemia (i.e., familial hypertriglyceridemia, hyperchylomicronemia), where personalized dietary adjustments are crucial for successful pregnancy outcomes. Pharmacological interventions and lipoprotein apheresis may be necessary for severe cases, though their use is often limited by factors such as cost, availability, and potential fetal risks. Despite the promise of advanced therapies, their widespread application remains constrained by limited studies and high costs. Thus, a personalized, multidisciplinary approach is essential for optimizing outcomes. This review provides a comprehensive overview of current strategies and evidence-based practices for managing dyslipidemia during pregnancy, emphasizing the balance of maternal and fetal health. Additionally, it discusses the physiological changes in lipid metabolism during pregnancy and their implications, particularly for women with inherited forms of dyslipidemia.

Real-world experience of long-term efficacy and safety of evinacumab in patients with homozygous familial hypercholesterolemia treated and untreated with lipoprotein apheresis

BACKGROUND

Evinacumab is an inhibitor of angiopoietin-like 3 protein (ANGPTL3) that offers a new approach for correcting high low-density lipoprotein-cholesterol (LDL-C) and may reduce the need or frequency for lipoprotein apheresis (LA) in patients with homozygous familial hypercholesterolemia (HoFH).

OBJECTIVE

We aimed to investigate the long-term efficacy and safety of evinacumab in patients with HoFH aged between 14 and 63 years on and off LA in real-world clinical practice.

METHODS

Evinacumab was administrated intravenously (15 mg /kg every 4 weeks) for the first 24 months in 7 patients with genetically confirmed HoFH, receiving best standard of lipid-lowering treatment and LA, followed by a subsequent compassionate extension period of approximately 12-month treatment with evinacumab without LA. Patient experience of evinacumab and health-related EuroQol (EQ-5D-3L) quality of life questionnaire were also assessed.

RESULTS

Compared with baseline, evinacumab resulted in sustained reductions in plasma LDL-C concentration of -43.4% and -54.2% at 30 and 36 months, respectively. All 7 HoFH patients achieved an LDL-C reduction >30% with 3 patients having on-treatment LDL-C level < 2.5 mmol/L (96 mg/dL). Evinacumab was well-tolerated, with no major adverse events reported or significant changes in liver enzyme concentrations. All FH patients agreed that evinacumab was acceptable and less physically demanding than LA. The mean EQ- utility score and visual analogue score were 0.966 and 78.6, respectively, which are comparable to the Italian general population.

CONCLUSIONS

Our findings suggest that evinacumab is a safe and effective treatment for high LDL-C that is acceptable to HoFH patients receiving and not receiving LA.

Society for Cardiovascular Magnetic Resonance 2023 Cases of SCMR case series

"Cases of SCMR" is a case series on the SCMR website (https://www.scmr.org) for the purpose of education. The cases reflect the clinical presentation and the use of cardiovascular magnetic resonance in the diagnosis and management of cardiovascular disease. The 2023 digital collection of cases is presented in this article.

Genome-wide association study and meta-analysis of phytosterols identifies a novel locus for serum levels of campesterol

Sitosterolemia is a rare inherited disorder caused by mutations in the ABCG5/ABCG8 genes. These genes encode proteins involved in the transport of plant sterols. Mutations in these genes lead to decreased excretion of phytosterols, which can accumulate in the body and lead to a variety of health problems, including premature coronary artery disease. We conducted the first genome-wide association study (GWAS) in the Middle East/North Africa population to identify genetic determinants of plant sterol levels in Qatari people. GWAS was performed on serum levels of β-sitosterol and campesterol using the Metabolon platform from Qatar Biobank (QBB) and genome sequence data provided by Qatar Genome Program. A trans-ancestry meta-analysis of data from our Qatari cohort with summary statistics from a previously published large cohort (9758 subjects) of European ancestry was conducted. Using conditional analysis, we identified two independent single nucleotide polymorphisms associated with β-sitosterol (rs145164937 and rs4299376), and two others with campesterol (rs7598542 and rs75901165) in the Qatari population in addition to previously reported variants. All of them map to the ABCG5/8 locus except rs75901165 which is located within the Intraflagellar Transport 43 (IFT43) gene. The meta-analysis replicated most of the reported variants, and our study provided significant support for the association of variants in SCARB1 and ABO with sitosterolemia. Evaluation of a polygenic risk score devised from European GWAS data showed moderate performance when applied to QBB (adjusted-R2 = 0.082). These findings provide new insights into the genetic architecture of phytosterol metabolism while showing the importance including under-represented populations in future GWAS studies.

Consensus document on diagnosis and management of familial hypercholesterolemia from the Italian Society for the Study of Atherosclerosis (SISA)

AIMS

Familial Hypercholesterolemia (FH) is a genetic disorder of lipoprotein metabolism that causes an increased risk of premature atherosclerotic cardiovascular disease (ASCVD). Although early diagnosis and treatment of FH can significantly improve the cardiovascular prognosis, this disorder is underdiagnosed and undertreated. For these reasons the Italian Society for the Study of Atherosclerosis (SISA) assembled a Consensus Panel with the task to provide guidelines for FH diagnosis and treatment.

DATA SYNTHESIS

Our guidelines include: i) an overview of the genetic complexity of FH and the role of candidate genes involved in LDL metabolism; ii) the prevalence of FH in the population; iii) the clinical criteria adopted for the diagnosis of FH; iv) the screening for ASCVD and the role of cardiovascular imaging techniques; v) the role of molecular diagnosis in establishing the genetic bases of the disorder; vi) the current therapeutic options in both heterozygous and homozygous FH. Treatment strategies and targets are currently based on low-density lipoprotein cholesterol (LDL-C) levels, as the prognosis of FH largely depends on the magnitude of LDL-C reduction achieved by lipid-lowering therapies. Statins with or without ezetimibe are the mainstay of treatment. Addition of novel medications like PCSK9 inhibitors, ANGPTL3 inhibitors or lomitapide in homozygous FH results in a further reduction of LDL-C levels. LDL apheresis is indicated in FH patients with inadequate response to cholesterol-lowering therapies.

CONCLUSION

FH is a common, treatable genetic disorder and, although our understanding of this disease has improved, many challenges still remain with regard to its identification and management.

Evinacumab in homozygous familial hypercholesterolaemia: long-term safety and efficacy

BACKGROUND AND AIMS

Homozygous familial hypercholesterolaemia (HoFH) is a rare genetic disorder characterized by severely elevated LDL cholesterol (LDL-C) and premature atherosclerotic cardiovascular disease. In the pivotal Phase 3 HoFH trial (NCT03399786), evinacumab significantly decreased LDL-C in patients with HoFH. This study assesses the long-term safety and efficacy of evinacumab in adult and adolescent patients with HoFH.

METHODS

In this open-label, single-arm, Phase 3 trial (NCT03409744), patients aged ≥12 years with HoFH who were evinacumab-naïve or had previously received evinacumab in other trials (evinacumab-continue) received intravenous evinacumab 15 mg/kg every 4 weeks with stable lipid-lowering therapy.

RESULTS

A total of 116 patients (adults: n = 102; adolescents: n = 14) were enrolled, of whom 57 (49.1%) were female. Patients were treated for a median (range) duration of 104.3 (28.3-196.3) weeks. Overall, treatment-emergent adverse events (TEAEs) and serious TEAEs were reported in 93 (80.2%) and 27 (23.3%) patients, respectively. Two (1.7%) deaths were reported (neither was considered related to evinacumab). Three (2.6%) patients discontinued due to TEAEs (none were considered related to evinacumab). From baseline to Week 24, evinacumab decreased mean LDL-C by 43.6% [mean (standard deviation, SD), 3.4 (3.2) mmol/L] in the overall population; mean LDL-C reduction in adults and adolescents was 41.7% [mean (SD), 3.2 (3.3) mmol/L] and 55.4% [mean (SD), 4.7 (2.5) mmol/L], respectively.

CONCLUSIONS

In this large cohort of patients with HoFH, evinacumab was generally well tolerated and markedly decreased LDL-C irrespective of age and sex. Moreover, the efficacy and safety of evinacumab was sustained over the long term.

Cardiovascular outcomes in patients with homozygous familial hypercholesterolaemia on lipoprotein apheresis initiated during childhood: long-term follow-up of an international cohort from two registries

BACKGROUND

Homozygous familial hypercholesterolaemia (HoFH) is a rare genetic disease characterised by extremely high plasma LDL cholesterol from birth, causing atherosclerotic cardiovascular disease at a young age. Lipoprotein apheresis in combination with lipid-lowering drugs effectively reduce LDL cholesterol, but long-term health outcomes of such treatment are unknown. We aimed to investigate the long-term cardiovascular outcomes associated with lipoprotein apheresis initiated in childhood or adolescence.

METHODS

In this cohort study, data were drawn from the HoFH International Clinical Collaboration (HICC) and the international registry for Children with Homozygous Hypercholesterolemia on Lipoprotein Apheresis (CHAIN). An overall cohort included patients diagnosed with HoFH aged 0-18 years who were alive and in follow-up between Jan 1, 2010, and Nov 8, 2021, and whose high plasma LDL cholesterol concentrations made them eligible for lipoprotein apheresis. To compare cardiovascular outcomes, patients who initiated lipoprotein apheresis in childhood (lipoprotein apheresis group) and patients who only received lipid-lowering drugs (pharmacotherapy-only group) were matched by sex and untreated plasma LDL cholesterol concentrations. The primary outcome was a composite of cardiovascular death, myocardial infarction, ischaemic stroke, percutaneous coronary intervention, coronary artery bypass grafting, aortic valve replacement, peripheral artery disease, carotid endarterectomy, angina pectoris, and supra-aortic or aortic stenosis (collectively referred to as atherosclerotic cardiovascular disease), for which survival analyses were performed in the matched cohort. Cox regression analyses were used to compare disease-free survival between cohorts and to calculate hazard ratio (HR) and 95% CI adjusted for sex, age at diagnosis, untreated plasma LDL cholesterol concentration, and number of lipid-lowering therapies other than lipoprotein apheresis.

FINDINGS

The overall cohort included 404 patients with a median age at diagnosis of 6·0 years (IQR 3·0-9·5) and median untreated plasma LDL cholesterol of 17·8 mmol/L (14·7-20·8). The matched cohorts included 250 patients (125 patients per group), with a median untreated LDL cholesterol of 17·2 mmol/L (14·8-19·7). Mean reduction in plasma LDL cholesterol concentrations between baseline and final follow-up was greater in the lipoprotein apheresis group (-55% [95% CI -60 to -51] vs -31% [-36 to -25]; p<0·0001). Patients in the lipoprotein apheresis group had longer atherosclerotic cardiovascular disease-free survival (adjusted HR 0·52 [95% CI 0·32-0·85]) and longer cardiovascular death-free survival (0·0301 [0·0021-0·4295]). Cardiovascular death was more common in the pharmacotherapy-only group than in the lipoprotein apheresis group (ten [8%] vs one [1%]; p=0·010), whereas median age at coronary artery bypass grafting was lower in the lipoprotein apheresis group than in the pharmacotherapy-only group (15·0 years [IQR 12·0-24·0] vs 30·5 years [19·0-33·8]; p=0·037).

INTERPRETATION

Among patients with HoFH, lipoprotein apheresis initiated during childhood and adolescence is associated with reduced long-term risk of atherosclerotic cardiovascular disease and death, and clear benefits of early initiation of high-frequency treatment on reducing plasma cholesterol were found. Consensus recommendations are now needed to guide more widespread and timely use of lipoprotein apheresis for children with HoFH, and research is required to further optimise treatment and ensure benefits of early and aggressive treatment delivery are balanced against effects on quality of life.

FUNDING

Amsterdam University Medical Centers, Location Academic Medical Center; Perelman School of Medicine at the University of Pennsylvania; European Atherosclerosis Society; and the US National Heart, Lung, and Blood Institute, National Institutes of Health.

LDLR c.89_92dup: a novel frameshift variation in familial hypercholesterolemia

BACKGROUND

Familial hypercholesterolemia (FH) is a common inherited metabolic disease that causes premature atherosclerosis, cardiovascular disease, and even death at a young age. Approximately 95% of FH-causing genetic variants that have been identified are in the LDLR gene. However, only 10% of the FH population worldwide has been diagnosed and adequately treated, due to the existence of numerous unidentified variants, uncertainties in the pathogenicity scoring of many variants, and a substantial number of individuals lacking access to genetic testing.

OBJECTIVE

The aim of this study was to identify a novel variant in the LDLR gene that causes FH in a Chinese family, thereby expanding the spectrum of FH-causing variants.

METHODS

Patients were recruited from Beijing Anzhen Hospital, Capital Medical University. FH diagnosis was made according to the Dutch Lipid Clinical Network (DLCN) criteria. Whole-exome sequencing (WES) was conducted to identify the FH-causing variant in the proband, and amplicon sequencing was used to verify the variant in his family members.

RESULTS

A three-generation Chinese family was recruited, and two FH patients were clinically diagnosed, both without known FH-causing variants. These two FH patients and another possible patient carried a novel variant, NC_000019.9(NM_000527.5):c.89_92dup (NP_000518.1:p.Phe32Argfs*21), in the ligand-binding domain of the low-density lipoprotein (LDL) receptor that led to a frameshift. The FH adults in the family showed severe clinical symptoms and statin therapy resistance.

CONCLUSION

This study identified a novel pathogenic LDLR variant, c.89_92dup, associated with severe FH clinical manifestations and statin therapy resistance.

Evinacumab and Cardiovascular Outcome in Patients With Homozygous Familial Hypercholesterolemia

BACKGROUND

Patients with homozygous familial hypercholesterolemia (HoFH) remain at very high cardiovascular risk despite the best standard of care lipid-lowering treatment. The addition of evinacumab, an angiopoietin-like protein 3 monoclonal antibody, more than halves low-density lipoprotein cholesterol in short-term studies. This study evaluated whether the evinacumab response was durable in the long term and improved cardiovascular outcome.

METHODS

The OLE ELIPSE HoFH (Open-Label Extension to Evinacumab Lipid Studies in Patients With HoFH) study included newly diagnosed patients and those completing the ELIPSE HoFH trial, on stable lipid-lowering therapy including lipoprotein apheresis but not lomitapide. All patients received evinacumab (15 mg/kg intravenously) every 4 weeks, with no change in concomitant lipid-lowering treatment during the first 6 months. The primary efficacy end points were the mean absolute and percentage changes in low-density lipoprotein cholesterol from baseline to 6 months. A key secondary end point was cardiovascular event-free survival, which was compared with a control HoFH cohort not treated with evinacumab or lomitapide and matched for age, sex, and lipoprotein apheresis, derived from French Registry of Familial hypercholesterolemia.

RESULTS

Twelve patients, 5 women and 7 men (12-57 years), were enrolled in 3 centers in France. At 6 months, the mean low-density lipoprotein cholesterol reduction with evinacumab was 3.7 mmol/L or 56% (from 6.5 mmol/L at baseline to 2.8 mmol/L; P<0.0001) and was sustained over the median 3.5-year follow-up. No patients on evinacumab experienced cardiovascular events versus 13 events for 5/21 (24%) over 4 years in the control cohort (likelihood P=0.0267).

CONCLUSIONS

Real-life, long-term evinacumab adjunctive to lipid-lowering therapy including lipoprotein apheresis led to sustained low-density lipoprotein cholesterol lowering and improved cardiovascular event-free survival of patients with HoFH.