The rebound of lipoproteins after LDL-apheresis. Kinetics and estimation of mean lipoprotein levels

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.

Clinical practice recommendations on lipoprotein apheresis for children with homozygous familial hypercholesterolaemia: An expert consensus statement from ERKNet and ESPN

Homozygous familial hypercholesterolaemia is a life-threatening genetic condition, which causes extremely elevated LDL-C levels and atherosclerotic cardiovascular disease very early in life. It is vital to start effective lipid-lowering treatment from diagnosis onwards. Even with dietary and current multimodal pharmaceutical lipid-lowering therapies, LDL-C treatment goals cannot be achieved in many children. Lipoprotein apheresis is an extracorporeal lipid-lowering treatment, which is used for decades, lowering serum LDL-C levels by more than 70% directly after the treatment. Data on the use of lipoprotein apheresis in children with homozygous familial hypercholesterolaemia mainly consists of case-reports and case-series, precluding strong evidence-based guidelines. We present a consensus statement on lipoprotein apheresis in children based on the current available evidence and opinions from experts in lipoprotein apheresis from over the world. It comprises practical statements regarding the indication, methods, treatment goals and follow-up of lipoprotein apheresis in children with homozygous familial hypercholesterolaemia and on the role of lipoprotein(a) and liver transplantation.

Long-term lipoprotein apheresis reduces cardiovascular events in high-risk patients with isolated lipoprotein(a) elevation

BACKGROUND

Elevated lipoprotein(a) (Lp(a)) is an established risk factor for cardiovascular disease (CVD). To date, the only approved treatment to lower Lp(a) is lipoprotein apheresis (LA). Previous studies have demonstrated that LA is effective in reducing cardiovascular (CV) risk in patients with elevated low-density lipoprotein cholesterol (LDL-C) and/or Lp(a). Here we report our long-term experience with LA and its effectiveness in reducing CVD events in patients with elevated Lp(a).

METHODS

This retrospective open-label, single-center study included 25 individuals with Lp(a) elevation >60 mg/dL and LDL-C < 2.59 mmol/L who had indication for LA. The primary endpoint of this study was the incidence of any CV event (determined by medical records) after initiation of LA.

RESULTS

Mean LA treatment duration was 7.1 years (min-max: 1-19 years). Median Lp(a) was reduced from 95.0 to 31.1 mg/dL after LA (-67.3 %, p < 0.0001). Mean LDL-C was reduced from 1.85 to 0.76 mmol/L after LA (-58.9 %, p < 0.0001). Prior LA, 81 CV events occurred in total (0.87 events/patient/year). During LA, 49 CV events occurred in total (0.24 events/patient/year; -0.63, p = 0.001). Yearly major adverse cardiac event (MACE) rate was reduced from 0.34 to 0.006 (-0.33, p = 0.0002). Similar results were obtained when considering only individuals with baseline LDL-C below 1.42 mmol/L.

CONCLUSION

In this observational study of a heterogeneous CV high-risk cohort with elevated Lp(a), LA reduced Lp(a) levels and was paralleled by a decrease in CV events and MACE. We recommend LA for patients with high Lp(a) who still have CV events despite optimal lipid-lowering medication and lifestyle changes.

Modern approaches to the management of homozygous familial hypercholesterolemia in the Middle East and North Africa

Homozygous familial hypercholesterolaemia (HoFH) is a severe form of FH in which inheritance of two defective or null mutations in genes associated with metabolism of low-density lipoprotein cholesterol (LDL-C) results in extremely high LDL-C, premature atherosclerotic cardiovascular disease (ASCVD) and mortality. Treatment of HoFH comprises a multi-modal approach of statins, ezetimibe, lipoprotein apheresis; and inhibitors of proprotein convertase subtilisin/kexin type, angiopoietin-like protein 3 (ANGPTL3) and microsomal triglyceride transfer protein. These treatments are generally costly, and patients also often require treatment for ASCVD consequent to HoFH. Therefore, in the interests of both economics and preservation of life, disease prevention via genetic screening and counselling is rapidly becoming a key element in the overall management of HoFH. Guidelines are available to assist diagnosis and treatment of HoFH; however, while advancements have been made in the management of the disease, there has been little systematic attention paid to prevention. Additionally, the Middle East/North Africa (MENA) region has a higher prevalence of HoFH than most other regions - chiefly due to consanguinity. This has led to the establishment of regional lipid clinics and awareness programs that have thrown education and awareness of HoFH into sharp focus. Incorporation of principles of prevention, education, awareness, and data from real-world use of existing therapeutics will significantly enhance the effectiveness of future guidelines for the management of HoFH, particularly in the MENA region.

Long-term outcomes of liver transplantation for homozygous familial hypercholesterolaemia in Australia and New Zealand

BACKGROUND AND AIMS

Homozygous familial hypercholesterolaemia (FH) causes severe cardiovascular disease from childhood. Conventional drug therapy is usually ineffective; lipoprotein apheresis (LA) is often required. Liver transplantation (LT) can correct the metabolic defect but is considered a treatment of last resort. Newer drugs including lomitapide and evinacumab might reduce the need for apheresis and LT. We sought to determine the long-term outcomes following LT in Australia and New Zealand.

METHODS

We analysed demographic, biochemical and clinical data from all patients in Australia and New Zealand who have received LT for homozygous FH, identified from the Australia and New Zealand Liver and Intestinal Transplant Registry.

RESULTS

Nine patients (five female; one deceased; seven aged between 3 and 6 years at the time of LT and two aged 22 and 26 years) were identified. Mean follow-up was 14.1 years (range 4-27). Baseline LDL-cholesterol off all treatment was 23 ± 4.1 mmol/L. Mean LDL-cholesterol on medical therapy (including maximal statin therapy in all patients, ezetimibe in three and LA in five) was 11 ± 5.7 mmol/L (p < 0.001). After LT, mean LDL-cholesterol was 2.6 ± 0.9 mmol/L (p = 0.004) with three patients remaining on statin therapy and none on LA. One patient died from acute myocardial infarction (AMI) three years after LT. Two patients required aortic valve replacement, more than 10 years after LT. The remaining six patients were asymptomatic after eight to 21 years of follow-up. No significant adverse events associated with immunosuppression were reported.

CONCLUSIONS

LT for homozygous FH was highly effective in achieving substantial long-term reduction in LDL-cholesterol concentrations in all nine patients. LT remains an option for severe cases of homozygous FH where drug therapy combined with apheresis is ineffective or unfeasible.

Clinical practice recommendations on lipoprotein apheresis for children with homozygous familial hypercholesterolemia: an expert consensus statement from ERKNet and ESPN

Homozygous familial hypercholesterolaemia is a life-threatening genetic condition, which causes extremely elevated LDL-C levels and atherosclerotic cardiovascular disease very early in life. It is vital to start effective lipid-lowering treatment from diagnosis onwards. Even with dietary and current multimodal pharmaceutical lipid-lowering therapies, LDL-C treatment goals cannot be achieved in many children. Lipoprotein apheresis is an extracorporeal lipid-lowering treatment, which is well established since three decades, lowering serum LDL-C levels by more than 70% per session. Data on the use of lipoprotein apheresis in children with homozygous familial hypercholesterolaemia mainly consists of case-reports and case-series, precluding strong evidence-based guidelines. We present a consensus statement on lipoprotein apheresis in children based on the current available evidence and opinions from experts in lipoprotein apheresis from over the world. It comprises practical statements regarding the indication, methods, treatment targets and follow-up of lipoprotein apheresis in children with homozygous familial hypercholesterolaemia and on the role of lipoprotein(a) and liver transplantation.

Impact of the severe familial hypercholesterolemia status on atherosclerotic risks

Risks of atherosclerotic events substantially vary even among patients with familial hypercholesterolemia (FH) with extremely high risk based on life-long exposure to high low-density lipoprotein cholesterol levels. This study aimed to examine the impact of the severe FH status defined by the International Atherosclerosis Society (IAS). Data of patients with FH (N = 1050, male = 490) who were admitted to Kanazawa University Hospital between 2000 and 2020 and who were followed up were retrospectively reviewed. The number of major adverse cardiac events (MACEs), including mortality associated with cardiovascular disease, acute coronary syndrome, and ischemic heart disease requiring coronary revascularization per 1000 person-years, was calculated. Hazard ratio was also calculated using Cox proportional model. Overall, 545 (51.9%) patients had severe FH. The median follow-up duration was 12.6 years. In total, 171 MACEs were recorded during the follow-up period. Severe FH was significantly associated with MACE (hazard ratio = 6.48, 95% confidence interval = 2.56-10.40, P = 1.2 × 10-5). The event rates per 1000 person-years in the primary prevention group of non-severe FH and severe FH, were 0.0 and 15.6, respectively. The event rates per 1000 person-years in the secondary prevention group of non-severe FH and severe FH, were 2.0 and 32.3, respectively. Patients with severe FH exhibited significantly higher risks in primary and secondary prevention settings. This simple criterion provides useful information for identifying patients with even higher risk who may need further management.

2023 Update on European Atherosclerosis Society Consensus Statement on Homozygous Familial Hypercholesterolaemia: new treatments and clinical guidance

This 2023 statement updates clinical guidance for homozygous familial hypercholesterolaemia (HoFH), explains the genetic complexity, and provides pragmatic recommendations to address inequities in HoFH care worldwide. Key strengths include updated criteria for the clinical diagnosis of HoFH and the recommendation to prioritize phenotypic features over genotype. Thus, a low-density lipoprotein cholesterol (LDL-C) >10 mmol/L (>400 mg/dL) is suggestive of HoFH and warrants further evaluation. The statement also provides state-of-the art discussion and guidance to clinicians for interpreting the results of genetic testing and for family planning and pregnancy. Therapeutic decisions are based on the LDL-C level. Combination LDL-C-lowering therapy-both pharmacologic intervention and lipoprotein apheresis (LA)-is foundational. Addition of novel, efficacious therapies (i.e. inhibitors of proprotein convertase subtilisin/kexin type 9, followed by evinacumab and/or lomitapide) offers potential to attain LDL-C goal or reduce the need for LA. To improve HoFH care around the world, the statement recommends the creation of national screening programmes, education to improve awareness, and management guidelines that account for the local realities of care, including access to specialist centres, treatments, and cost. This updated statement provides guidance that is crucial to early diagnosis, better care, and improved cardiovascular health for patients with HoFH worldwide.

Attainment of the low-density lipoprotein cholesterol treatment target and prognosis of heterozygous familial hypercholesterolemia

BACKGROUND AND AIMS

No previous study has investigated the association between attainment of low-density lipoprotein (LDL) cholesterol treatment target and better prognosis in patients with familial hypercholesterolemia (FH). The current research aimed to examine the association between attainment of LDL cholesterol treatment target and major adverse cardiac events (MACEs) in patients with FH to validate the current LDL cholesterol treatment targets in primary (<100 mg/dL) and secondary (<70 mg/dL) prevention settings.

METHODS

The data of patients with FH who were admitted to Kanazawa University Hospital between 2000 and 2020 and who were followed-up were retrospectively reviewed. The number of MACEs, including mortality associated with cardiovascular disease, unstable angina, and myocardial infarction per 1000 person-years, was calculated for each stratum for the attainment of LDL cholesterol target.

RESULTS

The median follow-up duration was 12.6 years. In total, 132 MACEs were recorded during the follow-up period. The numbers of patients who attained the LDL cholesterol target in the primary and secondary prevention groups were 228 (31.9%) and 40 (11.9%), respectively. The event rates per 1000 person-years for LDL cholesterol levels of <100 and ≥100 mg/dL in the primary prevention group were 2.6 and 4.4, respectively. The event rates per 1000 person-years for LDL cholesterol levels of <70 and ≥70 mg/dL in the secondary prevention group were 15.3 and 27.5, respectively.

CONCLUSIONS

Attainment of the LDL cholesterol target is associated with better prognosis in patients with FH. However, the attainment rate is currently inadequate among Japanese.

The development of lipoprotein apheresis in Saxony in the last years

METHODS

Three hundred thirty-nine patients (230 men, 109 women) treated with lipoprotein apheresis in Saxony, Germany, in 2018 are described in terms of age, lipid pattern, risk factors, cardiovascular events, medication, and number of new admissions since 2014, and the data are compared with figures from 2010 to 2013.

RESULTS

Patients were treated by 45.5 physicians in 16 lipoprotein apheresis centers. With about 10 patients per 100 000 inhabitants, the number of patients treated with lipoprotein apheresis in Saxony is twice as high as in Germany as a whole. The median treatment time was 3 years. Almost all patients had hypertension; type 2 diabetes mellitus was seen significantly more often in patients with low Lipoprotein(a). Cardiovascular events occurred in almost all patients before initiation of lipoprotein apheresis, under apheresis therapy the cardiovascular events rate was very low in this high-risk group. For some cardiovascular regions even no events could be observed.

CONCLUSIONS

The importance of lipoprotein apheresis in Saxony had been increasing from 2010 to 2018.

Repeated lipoprotein apheresis and immune response: Effects on different immune cell populations

BACKGROUND

Atherosclerosis is considered a chronic inflammation of arterial vessels with the involvement of several immune cells causing severe cardiovascular diseases. Lipoprotein apheresis (LA) improves cardiovascular conditions of patients with severely disturbed lipid metabolism. In this context, little is known about the impact of LA on various immune cell populations, especially over time.

METHODS

Immune cells of 18 LA-naïve patients starting weekly LA treatment were analyzed before and after four apheresis cycles over the course of 24 weeks by flow cytometry.

RESULTS AND CONCLUSIONS

An acute lowering effect of LA on T cell and natural killer (NK) cell subpopulations expressing CD69 was observed. The non-classical and intermediate monocyte subsets as well as HLA-DR⁺ 6-sulfo LacNAc⁺ monocytes were significantly reduced during the apheresis procedure. We conclude that LA has the capacity to alter various immune cell subsets. However, LA has mainly short-term effects than long-term consequences on proportions of immune cells.

Long-Term Efficacy and Safety of Evinacumab in Patients with Homozygous Familial Hypercholesterolemia: Real-World Clinical Experience

Homozygous familial hypercholesterolemia (HoFH) is a rare, genetic condition characterized by markedly elevated plasma low-density lipoprotein cholesterol (LDL-C) concentrations from birth and increased risk of premature atherosclerotic cardiovascular disease. Evinacumab is an inhibitor of angiopoietin-like 3 protein that offers a new approach for correcting high LDL-C in HoFH. Evinacumab was administered intravenously (15 mg/kg Q4W) for 24 months in 7 patients with genetically confirmed HoFH, receiving background lipoprotein apheresis (LA) and/or lipid-lowering treatment (LLT). Assessment of efficacy and safety were carried out before and after 24 months of evinacumab treatment. The LDL-C lowering effect of evinacumab without LA were also investigated in the 7 HoFH patients after a subsequent compassionate extension period. Twenty-four months of treatment with evinacumab against background LA and LLT resulted in a significant reduction in LDL-C (−46.8%; p < 0.001). LDL-C reduction with evinacumab was maintained during the compassionate extensions period in the absence of treatment with LA (−43.4%; mean follow-up of 208 ± 90 days). Evinacumab was well-tolerated, with no major adverse event reported or significant changes in liver and muscle enzyme concentrations. Our findings suggest that evinacumab is a safe and effective treatment for patients with HoFH receiving best standard of care in a routine setting.

Early Diagnosis and Treatments in Childhood are Associated with Better Prognosis in Patients with Familial Hypercholesterolemia

Objective

The early diagnosis and treatment initiation for children with familial hypercholesterolemia (FH) has been recommended in guidelines. However, there is limited data on the impact of early treatments on the prognosis of children with FH. To investigate if the early initiation of lipid-lowering therapies among Japanese pediatric patients with FH reduced the occurrence of cardiovascular disease (CVD) events in them.

Methods

We retrospectively investigated the occurrence of CVD events (myocardial infarction, unstable angina, or coronary artery revascularization) in patients with FH (N = 1050, male/female = 490/560), including 106 children below 20 years. We compared a variety of phenotypes, including genetic backgrounds, other complications, LDL cholesterol, medical therapies, and their prognoses between the patients’ diagnoses before the age of 20 years (children, mean age = 15 years) and after that age (adults, mean age = 52 years). Overall, 290 patients (27.6%) had a history of prior CVD events.

Results

The median follow-up duration was 12.6 [9.5–17.9] years. The baseline LDL cholesterol level, 239 mg/dL, dropped to 112 mg/dL with the treatments. The Achilles tendon thickness was significantly lower in children than that of adults (7.2 vs. 8.9 mm, P < 0.001). Over the follow-up duration, 119 CVD events were observed. Importantly, no CVD event was observed in children despite their median LDL cholesterol level at follow-up being significantly higher than that of adults (122 vs. 111 mg/dL, P < 0.001).

Conclusion

The likelihood of CVD events in those with FH diagnosed and treated in childhood is low.

Is Liver Transplant Curative in Homozygous Familial Hypercholesterolemia? A Review of Nine Global Cases

INTRODUCTION

Homozygous familial hypercholesterolemia (HoFH) is a rare, life-threatening, inherited condition characterized by extremely elevated levels of low-density lipoprotein cholesterol (LDL-C). Patients are at high risk of atherosclerotic cardiovascular disease, adverse cardiovascular events, and associated early mortality. Liver transplant is sometimes used with curative intent. The objective of the current case series was to evaluate the follow-up of a range of patients who have undergone liver transplant for the treatment of HoFH.

METHODS

Patients with clinical and/or genetic diagnoses of HoFH were treated according to local practices in four units in Europe and the Middle East. All patients underwent liver transplantation. Baseline and long-term follow-up data were collected, including LDL-C levels, DNA mutations, lipid-lowering medications, and complications due to surgery and immunosuppressive therapy.

RESULTS

Nine patients were included with up to 22 years' follow-up (mean ± SD 11.7 ± 11.7 years; range 0.5-28 years). Three of the patients died as a result of complications of transplant surgery (mortality rate 33%). Among the surviving six patients, four required continued lipid-lowering therapy (LLT) to maintain LDL-C levels and two patients show signs of increasing LDL-C levels that require management. One case (11%) required two consecutive transplants to achieve a viable graft and is awaiting a third transplant because of graft failure.

CONCLUSIONS

Liver transplant did not enable attainment of recommended LDL-C targets in most patients with HoFH, and the majority of patients still required post-transplant LLT. Liver transplant was not curative in most of the patients with HoFH followed. Guidelines suggest that transplant is a treatment of last resort if contemporary treatments are not available or possible.

[Lipoprotein apheresis : State of the art and case report of the longest HELP treatment worldwide]

Lipoprotein apheresis is an extracorporeal procedure for the treatment of patients with homozygous familial hypercholesterolemia, patients with severe treatment-resistant hypercholesterolemia and patients with lipoprotein(a) hypercholesterolemia, who show progressive atherosclerotic cardiovascular disease despite optimal treatment. This article reports on the historical developments of the procedures, the most frequently used methods for apheresis as well as the data situation on efficacy and tolerability. Randomized prospective studies on clinical outcomes are not available. Furthermore, the article reports on a patient with homozygous familial hypercholesterolemia and 34 years of treatment with heparin-induced extracorporeal low-density lipoprotein (LDL) precipitation (HELP) apheresis, the longest treatment of this kind worldwide. A second patient with combined heterozygous familial hypercholesterolemia and 31 years of liposorber and HELP apheresis is also described. The observational studies and the case reports demonstrate the safety and long-term tolerability of the procedure.

Vascular access for lipid apheresis: a challenge in young children with homozygous familial hypercholesterolemia

Background

Homozygous familial hypercholesterolemia (hoFH) is a rare genetic disorder leading to extremely increased LDL-cholesterol (LDL-C), resulting in high cardiovascular risk in early childhood. Lipid apheresis (LA) is an effective treatment and should be started as early as possible to prevent premature cardiovascular events. As peripheral punctures in children can be challenging due to small vessels and anxiety, this study aimed to evaluate feasibility and safety of central venous catheters (CVCs) as vascular access for LA in young children with hoFH.

Methods

Retrospective analysis (2016-2019) on four children with hoFH aged 3-5 years, performing weekly or biweekly LA with a CVC.

Results

LDL-C decreased by> 60%. In three children, the use of a permanent CVC for 698, 595, and 411 days, respectively, avoided difficult peripheral access, without the occurrence of occlusion or thrombosis. Unfortunately, one child had recurrent CVC-related infections and needed an arteriovenous fistula from the age of 5. Although the mean dwell time per catheter was 212 days, there were, as expected, severe side effects of early catheter infections with sepsis and accidental self-removal. Starting LA at an early age improved or stabilized carotid intima-media thickness (IMT) in three children. However, IMT did increase in one child caused by intolerance to peripheral punctures and LA interruption.

Conclusions

Permanent CVCs are a viable temporary access choice for LA in young children with hoFH until peripheral venipuncture is practicable. The risk of CVC-related infections needs to be taken into account.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-022-03192-7.

Lipoprotein(a): A Genetically Determined, Causal, and Prevalent Risk Factor for Atherosclerotic Cardiovascular Disease: A Scientific Statement From the American Heart Association

High levels of lipoprotein(a) [Lp(a)], an apoB100-containing lipoprotein, are an independent and causal risk factor for atherosclerotic cardiovascular diseases through mechanisms associated with increased atherogenesis, inflammation, and thrombosis. Lp(a) is predominantly a monogenic cardiovascular risk determinant, with ≈70% to ≥90% of interindividual heterogeneity in levels being genetically determined. The 2 major protein components of Lp(a) particles are apoB100 and apolipoprotein(a). Lp(a) remains a risk factor for cardiovascular disease development even in the setting of effective reduction of plasma low-density lipoprotein cholesterol and apoB100. Despite its demonstrated contribution to atherosclerotic cardiovascular disease burden, we presently lack standardization and harmonization of assays, universal guidelines for diagnosing and providing risk assessment, and targeted treatments to lower Lp(a). There is a clinical need to understand the genetic and biological basis for variation in Lp(a) levels and its relationship to disease in different ancestry groups. This scientific statement capitalizes on the expertise of a diverse basic science and clinical workgroup to highlight the history, biology, pathophysiology, and emerging clinical evidence in the Lp(a) field. Herein, we address key knowledge gaps and future directions required to mitigate the atherosclerotic cardiovascular disease risk attributable to elevated Lp(a) levels.

Use of apheresis in the age of new therapies for familial hypercholesterolaemia

PURPOSE OF REVIEW

Lipoprotein apheresis has been first line therapy for homozygous familial hypercholesterolaemia (FH) and other severe and refractory forms of dyslpidaemia for over 40 years but the recent advent of novel and potent LDL-lowering compounds necessitates a reappraisal of its role.

RECENT FINDINGS

During the past decade a substantial amount of evidence has accumulated describing the effect of LDL-lowering with apheresis and conventional drug therapy upon the cardiovascular outcomes associated with homozygous and statin-refractory heterozygous FH. This has necessitated re-defining the target levels of LDL cholesterol needed to arrest progression of atherosclerosis in these situations. At the same time, evidence has accrued regarding the pathogenicity of raised levels of lipoprotein (a) and the promising role of apheresis in mitigating the adverse effects of the latter. The latest advance in treatment has been the introduction of three classes of novel and potent LDL-lowering compounds in the shape of inhibitors of Propertin convertase subtilisin kexin 9 (PCSK9), microsomal triglyceride transfer protein and angiopoietin-like 3.

SUMMARY

These recent developments raise the question of whether these compounds will be used as adjuvants to bolster lipoprotein apheresis in FH homozygotes or whether they will render it obsolete, as is already occurring with PCSK9 inhibitors in FH heterozygotes.

Multiplex Protein Biomarker Profiling in Patients with Familial Hypercholesterolemia

Familial hypercholesterolemia (FH), is an autosomal dominant disorder caused by mutations in the LDLR, APOB, PCSK9, and APOE genes and is characterized by high plasma levels of total and low-density lipoprotein (LDL) cholesterol. Our study aimed to analyze the influences of two different therapies on a wide spectrum of plasma protein biomarkers of cardiovascular diseases. Plasma from FH patients under hypolipidemic therapy (N = 18; men = 8, age 55.4 ± 13.1 years) and patients under combined long-term LDL apheresis/hypolipidemic therapy (N = 14; men = 7; age 58.0 ± 13.6 years) were analyzed in our study. We measured a profile of 184 cardiovascular disease (CVD) associated proteins using a proximity extension assay (PEA). Hypolipidemic therapy significantly (all p < 0.01) influenced 10 plasma proteins (TM, DKK1, CCL3, CD4, PDGF subunit B, AGRP, IL18, THPO, and LOX1 decreased; ST2 increased). Under combined apheresis/hypolipidemic treatment, 18 plasma proteins (LDLR, PCSK9, MMP-3, GDF2, CTRC, SORT1, VEGFD, IL27, CCL24, and KIM1 decreased; OPN, COL1A1, KLK6, IL4RA, PLC, TNFR1, GLO1, and PTX3 increased) were significantly affected (all p < 0.006). Hypolipidemic treatment mainly affected biomarkers involved in vascular endothelial maintenance. Combined therapy influenced proteins that participate in cholesterol metabolism and inflammation.

Modern Approaches to Lower Lipoprotein(a) Concentrations and Consequences for Cardiovascular Diseases

Lipoprotein(a) (Lp(a)) is a low density lipoprotein particle that is associated with poor cardiovascular prognosis due to pro-atherogenic, pro-thrombotic, pro-inflammatory and pro-oxidative properties. Traditional lipid-lowering therapy does not provide a sufficient Lp(a) reduction. For PCSK9 inhibitors a small reduction of Lp(a) levels could be shown, which was associated with a reduction in cardiovascular events, independently of the effect on LDL cholesterol. Another option is inclisiran, for which no outcome data are available yet. Lipoprotein apheresis acutely and in the long run decreases Lp(a) levels and effectively improves cardiovascular prognosis in high-risk patients who cannot be satisfactorily treated with drugs. New drugs inhibiting the synthesis of apolipoprotein(a) (an antisense oligonucleotide (Pelacarsen) and two siRNA drugs) are studied. Unlike LDL-cholesterol, for Lp(a) no target value has been defined up to now. This overview presents data of modern capabilities of cardiovascular risk reduction by lowering Lp(a) level.

Long-term efficacy of lipoprotein apheresis and lomitapide in the treatment of homozygous familial hypercholesterolemia (HoFH): a cross-national retrospective survey

Background

Homozygous familial hypercholesterolemia (HoFH) is a rare life-threatening condition that represents a therapeutic challenge. The vast majority of HoFH patients fail to achieve LDL-C targets when treated with the standard protocol, which associates maximally tolerated dose of lipid-lowering medications with lipoprotein apheresis (LA). Lomitapide is an emerging therapy in HoFH, but its place in the treatment algorithm is disputed because a comparison of its long-term efficacy versus LA in reducing LDL-C burden is not available. We assessed changes in long-term LDL-C burden and goals achievement in two independent HoFH patients’ cohorts, one treated with lomitapide in Italy (n = 30) and the other with LA in France (n = 29).

Results

The two cohorts differed significantly for genotype (p = 0.004), baseline lipid profile (p < 0.001), age of treatment initiation (p < 0.001), occurrence of cardiovascular disease (p = 0.003) as well as follow-up duration (p < 0.001). The adjunct of lomitapide to conventional lipid-lowering therapies determined an additional 58.0% reduction of last visit LDL-C levels, compared to 37.1% when LA was added (p_adj = 0.004). Yearly on-treatment LDL-C < 70 mg/dl and < 55 mg/dl goals were only achieved in 45.5% and 13.5% of HoFH patients treated with lomitapide. The long-term exposure to LDL-C burden was found to be higher in LA than in Lomitapide cohort (13,236.1 ± 5492.1 vs. 11,656.6 ± 4730.9 mg/dL-year respectively, p_adj = 0.002). A trend towards fewer total cardiovascular events was observed in the Lomitapide than in the LA cohort.

Conclusions

In comparison with LA, lomitapide appears to provide a better control of LDL-C in HoFH. Further studies are needed to confirm this data and establish whether this translates into a reduction of cardiovascular risk.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-021-01999-8.

Familial Hypercholesterolemia: Global Burden and Approaches

PURPOSE OF REVIEW

Familial hypercholesterolemia (FH) is the most common genetic metabolic disorder characterized by markedly elevated LDL-C levels from birth leading to atherosclerotic cardiovascular disease (ASCVD) and premature deaths. The purpose of this review is to share the current knowledge in the diagnosis, risk estimation, and management of patients with FH in the light of recent evidence and guideline recommendations.

RECENT FINDINGS

Recent registries underscored the prevalence of FH as 1/200-250 translating to an almost 1500 million subjects suffering from FH worldwide. However, only a minority of FH patients are identified early and effectively treated. In most cases, mutations in the LDL-receptor (LDLR) gene and to a lesser degree in the apolipoprotein B-100 (APOB), proprotein convertase subtilisin/kexin type 9 (PCSK9), and the LDL-receptor adaptor protein 1 (LDLRAP1) genes cause FH. Diagnostic scores such as Dutch Lipid Clinic Network criteria using clinical manifestations are helpful in identifying FH. Traditional risk factors and high lipoprotein(a) affect the course of the disease. Vascular ultrasound imaging and coronary calcium scoring are helpful for further risk estimation of these patients. Getting to LDL-C goals is possible with currently available treatments including statins, ezetimibe, and PCSK9 inhibitors, as well as lipoprotein apheresis, lomitapide, and mipomersen in more severe phenotypes. Additionally, novel agents bempedoic acid, inclisiran, and evinacumab expanded the treatment choices for some patients with FH. Early diagnosis and initiation of LDL-C lowering are still required to achieve the greatest reduction in ASCVD morbidity and mortality in patients with FH. FH is a common genetic disorder characterized by markedly elevated LDL-C levels from birth onward, resulting in significantly increased risk for ASCVD. Despite major advances in our understanding of the disease and effective therapies, FH is still underdiagnosed and undertreated. Early initiation of LDL-C lowering by increased awareness of FH among the healthcare professionals, patients, and the public is necessary to achieve meaningful reduction in ASCVD morbidity and mortality in these patients.

Is treating severe He FH so easy? A combined treatment between lipoprotein apheresis and PCSK9 inhibitors

Despite advance in pharmacotherapy of lipid disorders, many heterozygous Familial Hypercholesterolemia patients do not achieve a desirable lipid target to significantly reduce the risk of atherosclerotic cardiovascular disease. The aim of the present work is to evaluate the interaction between Lipoprotein apheresis (LA) and PCSK9i in a small FH cohort in which the guidelines therapeutic target is not achieved. During one year, together with a complete adherence to PCSK9i therapy, we recorded a 3 to 5 LA sessions less per year in each patient. This therapeutic approach suggests: i) the possibility of increasing the number of patients treated with LA, ii) the improvement of their quality of life, and iii) the costs reduction for the single patient-treatment.

The scientific basis and future of lipoprotein apheresis

Lipoprotein apheresis plays a vital role in the management of the severe hyperlipidemias that predispose to atherosclerosis. Determinants of efficacy are the acute reduction in lipoproteins achieved by each apheresis procedure, their frequency, and the fractional catabolic rates and hence pool sizes of low-density lipoprotein (LDL) or lipoprotein (a) (Lp(a)) of the patient being treated. A useful criterion of the efficacy of apheresis plus lipid-lowering drug therapy is the decrease in the interval (time-averaged) mean of serum total or LDL cholesterol or Lp(a) between procedures, expressed as the percent decrease in the interval means below the maximal levels of these lipoproteins when off all treatment. Recent advances in lipid-lowering drug therapy may diminish the use of lipoprotein apheresis but will not abolish its unique role as a therapeutic "last chance saloon," especially for children and pregnant women with homozygous familial hypercholesterolemia.

Exposure to alirocumab during the first trimester of pregnancy: A case report

Background

Familial hypercholesterolemia can be efficiently treated with combined lipid‐lowering drugs. Lipid‐lowering drugs are usually withdrawn for pregnancy and breastfeeding, ideally preconception, followed by lipid apheresis, however, careful plans can be precipitated due to unexpected pregnancy.

Case

A 28‐year old woman with familial hypercholesterolemia due to heterozygous LDLR mutations had an LDL‐cholesterol level at 14.6 mmol/L and Lp(a) at 1150 mg/L. She required a three‐vessel coronary artery bypass graft, drug‐eluting stents, rosuvastatin, ezetimibe, and alirocumab at maximal dosage. Contraception was advised during the following 12 months, with a planned drug withdrawal to bridge with lipid apheresis, such as the direct adsorption of lipoproteins (DALI). However, an unplanned pregnancy required an abrupt stop of all oral medications at six gestational weeks, except for aspirin. Lipid apheresis controlled LDL‐cholesterol in the range of 4.9–7.9 mmol/L (before DALI session) to 1.2–3.2 mmol/L (after DALI session). Later, the regular pregnancy ultrasounds highlighted an isolated agenesis of the corpus callosum later confirmed by magnetic resonance imaging.

Conclusions

A causal link between the early pregnancy exposure to PCSK9 inhibitors (or statins and ezetimibe taken concomitantly) and the observed complete agenesis of the corpus callosum seems unlikely in this case. Guidelines do not specifically recommend preconception measures to lower fetal and/or maternal risks of patients with severe FH considering pregnancy. We argue that lipid apheresis and other measures should be discussed with women with FH and maternity project on an individual basis, until pharmacoepidemiology studies assessing the safety of PCSK9 inhibitors in pregnancy are available.

Monitoring of up to 15 years effects of lipoprotein apheresis on lipids, biomarkers of inflammation, and soluble endoglin in familial hypercholesterolemia patients

Background

Lipoprotein apheresis (LA) is considered as an add-on therapy for patients with familial hypercholesterolemia (FH). We aimed to analyze the data collected in the last 15 years from FH patients treated with LA, to elucidate the benefit of this procedure with respect to plasma lipids, biomarkers of inflammation, and endothelial dysfunction and soluble endoglin.

Results

14 patients (10 heterozygous FH patients (HeFH), 4 homozygous FH patients (HoFH)) were treated by long-term lipoprotein apheresis. Lipid levels were examined, and ELISA detected biomarkers of inflammation and soluble endoglin. Paired tests were used for intergroup comparisons, and a linear regression model served to estimate the influence of the number of days patients were treated with LA on the studied parameters. LA treatment was associated with a significant decrease of total cholesterol (TC), LDL-C, HDL-C, and apoB, in both HeFH and HoFH patients, after single apheresis and in a long-term period during the monitored interval of 15 years. Biomarkers of inflammation and endothelial dysfunction were reduced for soluble endoglin, hsCRP, and MCP-1, and sP-selectin after each procedure in some HeFH and HoFH patients.

Conclusions

LA treatment up to 15 years, reduced cholesterol levels, levels of biomarkers related to endothelial dysfunction, and inflammation not only after each procedure but also in the long-term evaluation in FH patients. We propose that long-term LA treatment improves lipid profile and endothelial dysfunction in familial hypercholesterolemia patients, suggesting a promising improvement in cardiovascular prognosis in most FH patients.

LDL Apheresis and Lp (a) Apheresis: A Clinician's Perspective

PURPOSE OF REVIEW

Lipoprotein apheresis is the most effective means of lipid-lowering therapy. However, it's a semi-invasive, time consuming, and chronic therapy with variable adherence. There are still no specific guideline recommendations for the management of patients on lipid apheresis. The purpose of this review is to discuss the clinical indications and major drawbacks of lipid apheresis in the light of recent evidence.

RECENT FINDINGS

Lipoprotein apheresis should be initiated at early ages and performed frequently to receive the expected cardiovascular benefits. However, in clinical practice, most patients experience ineffective apheresis and fail to reach lipid targets. This real-world failure is due to several factors including late diagnosis, delayed referral, and improper frequency of procedures. All these denote that awareness is still low among physicians. Another important factor is the semi-invasive, time consuming nature of the apheresis, leading to high refusal and low adherence rates. Moreover, apheresis decreases quality of life and increases the risk of depression. Mental status is also deteriorated in patients with familial hypercholesterolemia on lipid apheresis. New effective lipid lowering agents are underway with promising cardiovascular results. To overcome the drawbacks, a structured approach, including standardized protocols for lipoprotein apheresis with regular cardiovascular follow-up is warranted. New effective lipid lowering agents with documented cardiovascular benefit, should be integrated into the treatment algorithms of patients on lipoprotein apheresis.

Cardiovascular events in patients with familial hypercholesterolemia and hyperlipoproteinaemia (a): Indications for lipoprotein apheresis in Poland

BACKGROUND

Lipoprotein apheresis (LA) is a safe method of reducing atherogenic lipoproteins and improving cardiovascular (CV) outcomes. We aimed to assess the reductions in low-density lipoprotein cholesterol (LDL-C) and lipoprotein (a) [Lp(a)] levels in patients undergoing regular LA therapy and to evaluate its influence on the incidence rate of adverse cardiac and vascular events (ACVE) and major adverse cardiac events (MACE).

METHODS

A longitudinal study in Poland evaluated the prospective and retrospective observational data of 23 patients with hyperlipoproteinaemia (a) [hyper-Lp(a)] and familial hypercholesterolemia (FH), undergoing 1014 LA sessions between 2013 and 2020. Their pre- and post-apheresis LDL-C and Lp(a) levels were assessed to calculate the acute percent reductions. The time period used to evaluate annual rates of ACVE and MACE before and after initiation of LA was matched in each patient.

RESULTS

The pre-apheresis LDL-C and Lp(a) concentrations were 155 (107-228) (mg/dL) (median and interquartile range) and 0.56 (0.14-1.37) (g/L), respectively. LA therapy resulted in a reduction of LDL-C to 50 (30-73.5) (mg/dL) and of Lp(a) to 0.13 (0.05-0.34) (g/L), representing a percent reduction of 70.0% and 72.7% for LDL-C and Lp(a), respectively. We found a significant reduction in the annual rate of ACVE (0.365[0.0-0.585] vs (0.0[0.0-0.265]; P = .047) and MACE (0.365[0.0-0.585] vs 0.0[0.0-0.265]; P = .031).

CONCLUSIONS

The findings of our study indicate that LA treatment in patients with hyperlipoproteinaemia (a) and FH on maximally tolerated lipid lowering therapies leads to a substantial reduction in LDL-C and Lp(a) concentrations and lowers CV event rates in Polish patients.

Cardiovascular Outcome of Pediatric Patients With Bi-Allelic (Homozygous) Familial Hypercholesterolemia Before and After Initiation of Multimodal Lipid Lowering Therapy Including Lipoprotein Apheresis

Twenty-four patients with bi-allelic familial hypercholesterolemia commencing chronic lipoprotein apheresis (LA) at a mean age of 8.5 ± 3.1 years were analysed retrospectively and in part prospectively with a mean follow-up of 17.2 ± 5.6 years. Mean age at diagnosis was 6.3 ± 3.4 years. Untreated mean LDL-C concentrations were 752 mg/dl ± 193 mg/dl (19.5 mmol/l ± 5.0 mmol/l). Multimodal lipid lowering therapy including LA resulted in a mean LDL-C concentration of 184 mg/dl (4.8 mmol/l), which represents a 75.5% mean reduction. Proprotein convertase subtilisin/kexin type 9-antibodies contributed in 3 patients to LDL-C lowering with 5 patients remaining to be tested. After commencing chronic LA, 16 patients (67%) remained clinically stable with only subclinical findings of atherosclerotic cardiovascular disease (ASCVD), and neither cardiovascular events, nor need for vascular interventions or surgery. In 19 patients (79%), pathologic findings were detected at the aortic valve (AV), which in the majority were mild. AV replacement was required in 2 patients. Mean Lipoprotein(a) concentration was 42.4 mg/dl, 38% had >50 mg/dl. There was no overt correlation of AV pathologies with other ASCVD complications, or Lipoprotein(a) concentration. Physicochemical elimination of LDL particles by LA appears indispensable for patients with bi-allelic familial hypercholesterolemia and severe hypercholesterolemia to maximize the reduction of LDL-C. In conclusion, in this rare patient group regular assessment of both the AV, as well as all arteries accessible by ultrasound should be performed to adjust the intensity of multimodal lipid lowering therapy with the goal to prevent ASCVD events and aortic surgery.

Lipoprotein apheresis and PCSK9 inhibitors for severe familial hypercholesterolaemia: Experience from Australia and New Zealand

INTRODUCTION

Severe familial hypercholesterolaemia (FH) causes premature disability and death due to atherosclerotic cardiovascular disease and is refractory to standard lipid-lowering therapies. Lipoprotein apheresis (LA) has long been a standard of care for patients with severe FH, but is invasive, expensive and time-consuming for patients and their caregivers. Newer drug therapies, including the proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, may reduce the need for LA.

MATERIALS AND METHODS

We audited the records of 16 patients (eight homozygous, eight heterozygous) treated with LA in Australia and New Zealand, 14 of whom subsequently commenced PCSK9 inhibitor therapy. LA was performed by cascade filtration in all centres.

RESULTS

LDL-cholesterol was acutely lowered by 69 ± 7% in patients with homozygous FH and by 72 ± 9% in those with heterozygous FH, representing time-averaged reductions of 36 ± 12% and 34 ± 5%, respectively. LA was well-tolerated, and patients reported comparable quality of life to population and disease-related norms. After commencement of PCSK9 inhibitors, four of seven patients with homozygous FH had meaningful biochemical responses, with a reduction in the frequency of LA permitted in one patient and complete cessation in another. Four of seven patients with heterozygous FH were able to be managed without LA after commencing PCSK9 inhibitors.

CONCLUSION

While PCSK9 inhibitors have reduced the need for LA, some patients with severe FH continue to require LA, and will require it for the foreseeable future. However, emerging therapies, including angiopoetin-like 3 inhibitors, may further reduce the need for LA.

Lipoprotein Apheresis and Proprotein Convertase Subtilisin/Kexin Type 9 Inhibitors in Patients With Heterozygous Familial Hypercholesterolemia: A One Center Study

AIM

We evaluated the lipid-lowering (LL) effect of proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) in patients with heterozygous familial hypercholesterolemia (HeFH) treated with LL-drugs and lipoprotein apheresis (LA).

PATIENTS AND METHODS

The PCSK9i treatment (evolocumab 420 mg/4 weeks, alirocumab 150 mg/2 weeks, or alirocumab 75 mg/2 weeks: 9, 6, and 2 patients, respectively) was initiated in patients with HeFH (n = 17; aged 35-69 years, 10 men, previously treated with statins + ezetimibe ± colesevelam and LA sessions for 2-12 years). A lipid profile was obtained before and immediately after the LA session and before, 1 and 2 months after switching to PCSK9i treatment. The duration of PCSK9i therapy ranged from 3 to 18 months.

RESULTS

Median total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides (TG) levels before LA were 268, 198, 46, and 126 mg/dL, respectively, and decreased (at the end of the LA session) to 117, 50, 40, and 51 mg/dL, respectively (P < .001 for TC and P = .001 for all other comparisons). The median time-averaged LDL-C levels following LA were 155 (121, 176; median [25th, 75th percentile]) mg/dL. Median TC, LDL-C, and TG levels before PCSK9i therapy were 269, 190, and 127 mg/dL and decreased to 152, 100, and 95 mg/dL, respectively (P = .002, P < .002, and P < .03, respectively). Steady LDL-C levels with PCSK9i treatment were significantly lower compared with time-averaged LDL-C levels following LA (median value: 100 vs 155 mg/dL; P = .008). With PCSK9i, from 13 patients with CHD, 6 (46.1%) patients achieved LDL-C <70 mg/dL, and 2 patients (15.4%) achieved LDL-C <100 mg/dL. Lipoprotein apheresis was discontinued in all patients except for 2 who continued once monthly.

CONCLUSIONS

PCSK9i can reduce LDL-C more consistently over time compared with a transient decrease following LA in HeFH patients. PCSK9i therapy may reduce the frequency of LA. Larger trials are required to establish the clinical implications of PCSK9i in patients previously on LA.

Why Some Patients Undergoing Lipoprotein Apheresis Therapy Develop New Cardiovascular Events?

Lipoprotein apheresis (LA) is an effective tool to reduce cardiovascular events (CVEs) in high-risk patients with elevations of low density lipoprotein-cholesterol (LDL-C) and/or Lipoprotein(a) (Lp(a)). All patients included into this retrospective analysis had experienced CVEs before the start of the LA therapy. We compared personal and lab data in two groups: CVEx/0 (n 60) with no new events during LA therapy, CVEx/1+ (n 48) with at least one new event. Patients of Group CVEx/1+ were about 5 years older when they had started the extracorporeal therapy, and they experienced more CVEs prior to that timepoint. There was a positive correlation between the number of CVEs before and during LA therapy. No differences were seen with respect to lipid concentrations, even after a correction of LDL-C concentrations for the LDL-C transported with Lp(a) particles. LA sessions effectively reduced both LDL-C and Lp(a). Lp(a) levels measured before LA sessions were lower than those measured initially. It appeared difficult to reach the target values for LDL-C published in the ESC/EAS Guideline in 2019, although all patients were maximally treated including drugs when tolerated. In conclusion, it will be important to initiate an LA therapy earlier, at least after a second CVE and at a younger age.

Lomitapide-a Microsomal Triglyceride Transfer Protein Inhibitor for Homozygous Familial Hypercholesterolemia

PURPOSE OF REVIEW

Homozygous familial hypercholesterolemia (HoFH) is a rare, genetic condition characterized by high levels of Low density lipoprotein cholesterol (LDL-C); overt, early-onset atherosclerotic cardiovascular disease (ASCVD); and premature cardiovascular events and mortality. Lomitapide is a first-in-class microsomal triglyceride transfer protein inhibitor for the treatment of HoFH. This review provides an update on data emerging from real-world studies of lomitapide following on from its pivotal phase 3 clinical trial in HoFH.

RECENT FINDINGS

Recent registry data have confirmed that HoFH is characterized by delayed diagnosis, with many patients not receiving effective therapy until they are approaching the age when major adverse cardiovascular events may occur. Data from case series of varying sizes, and from a 163-patient registry of HoFH patients receiving lomitapide, have demonstrated that lomitapide doses are lower and adverse events less severe than in the phase 3 study. Lomitapide enables many patients to reach European Atherosclerosis Society LDL-C targets. Some patients are able to reduce frequency of lipoprotein apheresis or, in some cases, stop the procedure altogether-unless there is significant elevation of lipoprotein (a). Modelling analyses based on historical and clinical trial data indicate that lomitapide has the potential to improve cardiovascular outcomes and survival in HoFH. Real-world clinical experience with lomitapide has shown the drug to be effective with manageable, less marked adverse events than in formal clinical studies. Event modelling data suggest a survival benefit with lomitapide in HoFH.

Actual situation of lipoprotein apheresis in patients with elevated lipoprotein(a) levels

An elevation of lipoprotein(a) (Lp(a)) is an internationally recognized atherogenic risk factor, documented in epidemiological studies, in studies with Mendelian randomization and in genome-wide association studies (GWAS). At present, no drug is available to effectively reduce its concentration. In Germany, an elevation of Lp(a) associated with progressive cardiovascular diseases is officially recognized as an indication for a lipoprotein apheresis (LA). The number of patients who were treated with LA with this abnormality was steadily increasing in the years 2013-2016 - the official data are reported. In all new patients, who started to be treated at our LA center in 2017 (n = 20) the increased Lp(a) was a main indication for extracorporeal therapy, though some of them also showed clearly elevated LDL cholesterol (LDL-C) concentrations despite being treated with a maximal tolerated lipid-lowering drug therapy. A diabetes mellitus was seen in 5 patients. The higher was the Lp(a) level before the first LA session, the higher was the cardiovascular risk. Lp(a) concentrations measured before LA sessions were usually about 20% lower than those before the start of the LA therapy. Acutely, Lp(a) levels were reduced by about 70%. Following LA sessions the Lp(a) levels increased and in the majority reach pre-session concentrations after one week. Thus a weekly interval is best for the patients, but a few may need two sessions per week to stop the progress of atherosclerosis. The interval mean values were about 39% lower than previous levels. Several papers had been published showing a higher efficiency of LA therapy on the incidence of cardiovascular events in patients with high Lp(a) values when comparing with hypercholesterolemic patients with normal Lp(a) concentrations. Russian specific anti-Lp(a) columns positively affected coronary atherosclerosis. PCSK9 inhibitors reduce Lp(a) concentrations in many patients and in this way have a positive impact on cardiovascular outcomes. In the future, an antisense oligonucleotide against apolipoprotein(a) may be an alternative therapeutic option, provided a clear-cut reduction of cardiovascular events will be demonstrated.

Mental status and physical activity in patients with homozygous familial hypercholesterolemia: A subgroup analysis of a nationwide survey (A-HIT1 registry)

BACKGROUND

Homozygous familial hypercholesterolemia (HoFH) is a rare, life-threatening disease due to high serum low-density lipoprotein (LDL) cholesterol levels. LDL cholesterol-lowering interventions are fundamental for patients with HoFH.

OBJECTIVE

It was aimed to investigate the association between the mental status of patients with HoFH and healthy lifestyle behaviors.

METHODS

This subgroup analysis of the A-HIT1 population included the data of patients aged ≥18 years with a clinical diagnosis of HoFH undergoing therapeutic LDL apheresis. Besides the demographic and clinical characteristics of patients, healthy lifestyle behaviors were assessed, and psychiatric symptoms were screened by Symptom Check List (SCL-90-R).

RESULTS

The highest percentage for pathology was observed in dimensions of obsessive-compulsive, somatization, interpersonal sensitivity, and depression in SCL-90-R. Patients with any cardiovascular condition have more psychiatric symptoms in different fields of SCL-90-R. The outcomes of the correlative analysis indicated that lower the age of the first coronary event better the psychiatric status, probably denoting a better adaptation to disease and its treatment. Among 68 patients, 36 patients were not exercising regularly. Patients with regular physical activity had significantly lower scores in most dimensions of SCL-90-R and there was no association between regular physical activity and other investigated variables. The strongest predictor of regular exercising was global severity index of SCL-90-R.

CONCLUSION

In the HoFH population, there was a high prevalence of mental disturbances. Better psychiatric status was associated with regular exercising. Therefore, assessing the mental status of patients with HoFH and referring patients in need, to a psychiatrist, may improve the outcome of patients.

Homozygous familial hypercholesterolemia with severe involvement of the aortic valve-A sibling-controlled case study on the efficacy of lipoprotein apheresis

BACKGROUND

Homozygous familial hypercholesterolemia (hoFH) can cause severe atherosclerotic cardiovascular disease (ASCVD) in early infancy. Diagnosis and initiation of effective lipid-lowering therapy (LLT) are recommended as early as possible to prevent ASCVD-related morbidity and mortality.

METHODS

The clinical courses of a pair of siblings with an identical hoFH genotype, who exhibited major similarities of their clinical phenotype were analyzed in a case-control fashion including the family.

RESULTS

The older sibling was diagnosed with hoFH at the age of 4. Untreated LDL-cholesterol (LDL-C) was 17 mmol/L (660 mg/dL). LLT including lipoprotein apheresis (LA) was initiated and has been successful for 8 years now. A reduction of estimated cholesterol burden by 74% was achieved by LA and combined drug therapy including statins and ezetimibe. The efficacy of escalation of drug therapy was limited because the underlying LDL receptor (LDLR) mutation in the family resulted in substantially reduced receptor function. Treatment with proprotein convertase subtilisin-kexin type 9 (PCSK9)-antibodies failed. His younger brother died at the age of 2 years shortly after the hoFH diagnosis of the elder sibling. Postmortem examination revealed advanced aortic root atheroma and aortic valve stenosis. In the older sibling, aortic valve stenosis and insufficiency were treated at the age of 9 years with mechanical aortic valve replacement.

CONCLUSIONS

LLT including LA should be initiated as early as possible following the diagnosis of hoFH with very high LDL-C levels. With the same genotype, the phenotype of hoFH can exhibit similar patterns but outcome is substantially related to treatment.

Biomarker variability and cardiovascular disease residual risk

PURPOSE OF REVIEW

A number of cohorts and clinical trials have reported observing associations between intraindividual variation of biomarkers and manifestations of cardiovascular disease (CVD).

RECENT FINDINGS

Intraindividual (or 'visit-to-visit') variability of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), apolipoprotein B, high-density lipoprotein cholesterol (HDL-C), non-HDL-C, and triglyceride have all been found to associate with CVD outcomes, independent of their mean absolute levels, independent of each other, and independent of other traditional risk factors. These findings have been confirmed recently in large cohort studies in different populations, and in post-hoc analyses of clinical trial data. Lipoprotein variability has been associated with myocardial infarction, other arterial disease including cerebrovascular, and with cardiovascular and overall mortality. The association of higher variability of LDL-C with atheroma progression has also been assessed directly using intravascular ultrasound and carotid intima-media thickness. The lipoprotein variability of an individual contributes to their residual risk of CVD, although the mechanism remains unclear.

SUMMARY

There is compelling evidence that lipoprotein variability contributes to residual risk; however, a more standardized approach is required before the risk attributable to variability can be assessed effectively.

Guidelines on the Use of Therapeutic Apheresis in Clinical Practice - Evidence-Based Approach from the Writing Committee of the American Society for Apheresis: The Eighth Special Issue

The American Society for Apheresis (ASFA) Journal of Clinical Apheresis (JCA) Special Issue Writing Committee is charged with reviewing, updating and categorizing indications for the evidence-based use of therapeutic apheresis (TA) in human disease. Since the 2007 JCA Special Issue (Fourth Edition), the committee has incorporated systematic review and evidence-based approaches in the grading and categorization of apheresis indications. This Eighth Edition of the JCA Special Issue continues to maintain this methodology and rigor in order to make recommendations on the use of apheresis in a wide variety of diseases/conditions. The JCA Eighth Edition, like its predecessor, continues to apply the category and grading system definitions in fact sheets. The general layout and concept of a fact sheet that was introduced in the Fourth Edition, has largely been maintained in this edition. Each fact sheet succinctly summarizes the evidence for the use of TA in a specific disease entity or medical condition. The Eighth Edition comprises 84 fact sheets for relevant diseases and medical conditions, with 157 graded and categorized indications and/or TA modalities. The Eighth Edition of the JCA Special Issue seeks to continue to serve as a key resource that guides the utilization of TA in the treatment of human disease.

What have we learned from Turkish familial hypercholesterolemia registries (A-HIT1 and A-HIT2)?

BACKGROUND AND AIMS

Familial hypercholesterolemia (FH) is a common genetic disease of high-level cholesterol leading to premature atherosclerosis. One of the key aspects to overcome FH burden is the generation of large-scale reliable data in terms of registries. This manuscript underlines the important results of nation-wide Turkish FH registries (A-HIT1 and A-HIT2).

METHODS

A-HIT1 is a survey of homozygous FH patients undergoing low density lipoprotein (LDL) apheresis (LA). A-HIT2 is a registry of adult FH patients (homozygous and heterozygous) admitted to outpatient clinics. Both registries used clinical diagnosis of FH.

RESULTS

A-HIT1 evaluated 88 patients (27 ± 11 years, 41 women) in 19 centers. All patients were receiving regular LA. There was a 7.37 ± 7.1-year delay between diagnosis and initiation of LA. LDL-cholesterol levels reached the target only in 5 cases. Mean frequency of apheresis sessions was 19 ± 13 days. None of the centers had a standardized approach for LA. Mean frequency of apheresis sessions was every 19 ± 13 (7-90) days. Only 2 centers were aware of the target LDL levels. A-HIT2 enrolled 1071 FH patients (53 ± 8 years, 606 women) from 31 outpatients clinics specialized in cardiology (27), internal medicine (1), and endocrinology (3); 96.4% were heterozygous. 459 patients were on statin treatment. LDL targets were attained in 23 patients (2.1% of the whole population, 5% receiving statin) on treatment. However, 66% of statin-receiving patients were on intense doses of statins. Awareness of FH was 9.5% in the whole patient population.

CONCLUSIONS

The first nationwide FH registries revealed that FH is still undertreated even in specialized centers in Turkey. Additional effective treatment regiments are urgently needed.

Microsomal triglyceride transfer protein inhibitor (lomitapide) efficacy in the treatment of patients with homozygous familial hypercholesterolaemia

Aims

The aim of this study was to evaluate the effect of microsomal triglyceride transfer protein inhibitor (lomitapide) in patients with homozygous familial hypercholesterolaemia.

Methods and results

In 12 homozygous familial hypercholesterolaemia patients treated with lipid-lowering drugs ± biweekly lipoprotein apheresis sessions (nine patients), daily lomitapide was added. The lipid profile (total cholesterol, low-density lipoprotein cholesterol, triglycerides, high-density lipoprotein cholesterol) before and after lomitapide treatment was evaluated. The follow-up period with lomitapide treatment was 3–24 months (13.8 ± 7.9). The median baseline low-density lipoprotein cholesterol level was 900 mg/dl (348–1070), after lipid-lowering drugs therapy was 383.5 mg/dl (214–866) and after lipid-lowering drugs + time-averaged level was 288 mg/dl (183.7–716.6). The addition of lomitapide lowered low-density lipoprotein cholesterol levels further by 56.8% compared to lipid-lowering drugs alone (mean reduction 262, 95% confidence interval (105.5–418.7), p = 0.005) and by 54% (mean reduction 182.9, 95% confidence interval (−342 – −23), p = 0.031) comparing to lipid-lowering drugs + lipoprotein apheresis (time-averaged level). The time-averaged level of low-density lipoprotein cholesterol in lipid-lowering drugs + lipoprotein apheresis patients compared with lipid-lowering drugs + lomitapide was 54% in favour of lomitapide ( p = 0.031).

Conclusions

Treatment with lomitapide in homozygous familial hypercholesterolaemia patients has a beneficial effect with a constant decrease of low-density lipoprotein cholesterol by 57% compared with classical lipid-lowering therapy and by 54% compared with classical lipid-lowering therapy and time-averaged level of low-density lipoprotein cholesterol.

Real-World Outcomes with Lomitapide Use in Paediatric Patients with Homozygous Familial Hypercholesterolaemia

INTRODUCTION

Homozygous familial hypercholesterolaemia (HoFH) is a rare, autosomal disease affecting the clearance of low-density lipoprotein cholesterol (LDL-C) from circulation, and leading to early-onset atherosclerotic cardiovascular disease (ASCVD). Treatment consists mainly of statins, lipoprotein apheresis (LA) and, more recently, the microsomal triglyceride transfer protein inhibitor lomitapide. Lomitapide is not licensed for use in children, but has been made available through an expanded access programme or on a named patient basis.

METHODS

This case series includes 11 HoFH patients in 10 different centres in eight countries, less than 18 years of age (mean 11.6 ± 1.1 years, 64% male), with signs of ASCVD, and who have received treatment with lomitapide (mean dose 24.5 ± 4.3 mg/day; mean exposure 20.0 ± 2.9 months). Background lipid-lowering therapy was given according to local protocols. Lomitapide was commenced with a stepwise dose escalation from 2.5 mg or 5 mg/day; dietary advice and vitamin supplements were provided as per the product label for adults. Laboratory analysis was conducted as part of regular clinical care.

RESULTS

In the 11 cases, mean baseline LDL-C was 419 ± 74.6 mg/dL and was markedly reduced by lomitapide to a nadir of 176.7 ± 46.3 mg/dL (58.4 ± 6.8% decrease). Six patients achieved recommended target levels for children below 135 mg/dL, five of whom had LA frequency reduced. In one case, LDL-C levels were close to target when lomitapide was started but remained stable despite 75% reduction in LA frequency (from twice weekly to biweekly). Adverse events were mainly gastrointestinal in nature, occurred early in the treatment course and were well managed. Three patients with excursions in liver function tests were managed chiefly without intervention; two patients had decreases in lomitapide dose.

CONCLUSIONS

Lomitapide demonstrated promising effectiveness in paediatric HoFH patients. Adverse events were manageable, and the clinical profile of the drug is apparently similar to that in adult patients.

FUNDING

Amryt Pharma.

Current Role of Lipoprotein Apheresis

Purpose of Review

Lipoprotein apheresis is a very efficient but time-consuming and expensive method of lowering levels of low-density lipoprotein cholesterol, lipoprotein(a)) and other apoB containing lipoproteins, including triglyceride-rich lipoproteins. First introduced almost 45 years ago, it has long been a therapy of “last resort” for dyslipidaemias that cannot otherwise be managed. In recent years new, very potent lipid-lowering drugs have been developed and the purpose of this review is to define the role of lipoprotein apheresis in the current setting.

Recent Findings

Lipoprotein apheresis still plays an important role in managing patients with homozygous FH and some patients with other forms of hypercholesterolaemia and cardiovascular disease. In particular, patients not achieving treatment goals despite modern lipid-lowering drugs, either because these are not tolerated or the response is insufficient. Recently, lipoprotein(a) has emerged as an important cardiovascular risk factor and lipoprotein apheresis has been used to decrease lipoprotein(a) concentrations in patients with marked elevations and cardiovascular disease. However, there is considerable heterogeneity concerning the recommendations by scientific bodies as to which patient groups should be treated with lipoprotein apheresis.

Summary

Lipoprotein apheresis remains an important tool for the management of patients with severe drug-resistant dyslipidaemias, especially those with homozygous FH.