Efficacy of Lomitapide in the Treatment of Familial Homozygous Hypercholesterolemia: Results of a Real-World Clinical Experience in Italy

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.

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.

Lomitapide: navigating cardiovascular challenges with innovative therapies

Dyslipidemia is the most significant risk factor for cardiovascular diseases (CVDs) Secondary dyslipidemia: its treatments and association with atherosclerosis. Glob Health Med, Efficacy and safety of saroglitazar for the management of dyslipidemia: A systematic review and meta-analysis of interventional studies. The current treatment strategies for managing dyslipidemia focus on reducing low-density lipoprotein cholesterol (LDL-C) to minimize the risks of atherosclerosis and myocardial infarction (MI). Homozygous Familial Hypercholesterolemia (HoFH) is an inherited autosomal dominant disease caused by a mutation in the LDL receptor (LDLr), which can lead to extremely high levels of LDL-C The Beneficial Effect of Lomitapide on the Cardiovascular System in LDLr(-/-) Mice with Obesity, The microsomal triglyceride transfer protein inhibitor lomitapide improves vascular function in mice with obesity. Although statin therapy has been the primary treatment for dyslipidemia, HoFH patients do not respond well to statins, requiring alternative therapies. Microsomal triglyceride transfer protein (MTP) inhibition has emerged as a potential therapeutic target for treating HoFH. MTP is primarily responsible for transferring triglyceride and other lipids into apolipoprotein B (ApoB) during the assembly of very low-density lipoprotein (VLDL) particles in the liver. Lomitapide, an inhibitor of MTP, has been approved for treatingof HoFH adults. Unlike statins, lomitapide does not act on the LDLr to reduce cholesterol. Instead, lomitapide lowers the levels of ApoB-containing proteins, primarily VLDL, eventually decreasing LDL-C levels. Studies have shown that lomitapide can reduce LDL-C levels by more than 50% in patients with HoFH who have failed to respond adequately to other treatments. Lowering LDL-C levels is important for preventing atherosclerosis, reducing cardiovascular risk, improving endothelial function, and promoting overall cardiovascular health, especially for patients with HoFH Efficacy and safety of a microsomal triglyceride transfer protein inhibitor in patients with homozygous familial hypercholesterolaemia: a single-arm, open-label, phase 3 study. This review paper focuses on research findings regarding the therapeutic benefits of lomitapide, highlighting its effectiveness in lowering cholesterol levels and reducing the risk of CVDs The microsomal triglyceride transfer protein inhibitor lomitapide improves vascular function in mice with obesity.

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.

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.

Lomitapide: A Medication Use Evaluation and a Formulary Perspective

Introduction

Lomitapide is approved for lowering low-density lipoprotein cholesterol (LDL-C) in homozygous familial hypercholesterolemia, which is a rare genetic disorder. The evidence regarding its safety and efficacy from a small clinical trial requires further validation for effectiveness and safety in the real world. This study aimed to use institutional data on the effectiveness and safety of lomitapide to assist in formulating a perspective on adding it to the formulary.

Methods

This was a retrospective review of patients who were actively prescribed lomitapide at King Abdulaziz Medical City, Riyadh, Saudi Arabia, from 2019 to 2022. Data collection included demographics, confirmed gene mutation results, duration of lomitapide therapy, baseline, on-treatment, last LDL-C levels, percent reduction in LDL-C after 1-3 months of therapy (whichever was first available), other LDL-C lowering therapies used, liver function tests, adverse effects, and compliance.

Results

Eight adult patients were included in the review, with a mean age of 25.5 years. Approximately 75% were female, and the duration of treatment with lomitapide ranged from 9 months to 3 years. None of the patients were on continuous LDL apheresis. The mean baseline LDL-C at presentation to our facility was 17.2 mmol/L (range, 11.78-21.97 mmol/L), the mean percent drop in LDL-C with lomitapide was 34.1% (range, 0%-87%), gastrointestinal disturbances were documented in 50% of the patients, and no cases of severe liver toxicities or increase in liver enzymes were seen.

Conclusions

In our cohort of adult patients, lomitapide showed an overall modest reduction in LDL-C, with no cases of increase in liver enzymes and documented intolerance, indicating that most patients were likely noncompliant. This review revealed important considerations when reimbursing expensive medications for rare diseases. Real-world evidence in real-time can support healthcare systems in price negotiations and reaching mutual agreements that can eventually improve patient access to care.

Emerging therapies for refractory hypercholesterolemia: a narrative review

Refractory hypercholesterolemia (RH) is characterized by the failure of patients to achieve therapeutic targets for low-density lipoprotein-cholesterol (LDL-C) despite receiving maximal tolerable doses of standard lipid-lowering treatments. It predominantly impacts individuals with familial hypercholesterolemia (FH), thereby elevating the risk of cardiovascular complications. The prevalence of RH is now recognized to be substantially greater than previously thought. This review provides a comprehensive insight into current and emerging therapies for RH patients, including groundbreaking genetic-based therapeutic approaches. The review places emphasis on the dependency of therapies on low-density lipoprotein receptors (LDLRs) and highlights the critical role of considering LDLR activity in RH patients for individualization of the treatment.

Real-world safety and efficacy of lomitapide in homozygous familial hypercholesterolemia: interim report of special-use survey in Japan

Aim: To evaluate the safety and efficacy of lomitapide in real-world clinical practice in Japan. Patients & methods: Interim analysis of 39 patients with homozygous familial hypercholesterolemia from an all-case surveillance study. Results: Median lomitapide dose (across 42 months) was 9.8 mg/day. 74 drug-related adverse events (AEs) were reported in 24 (61.5%) patients, including 14 (35.9%) with liver-related AEs, 19 (48.7%) with gastrointestinal disorders and 1 (2.6%) bleeding disorder. Lomitapide dose was reduced for 39.2% of drug-related AEs, withdrawn temporarily for 12.2%, and discontinued for 1 event (1.4%). Mean ± SD blood LDL-C level decreased from 225.9 ± 172.0 mg/dl (5.8 ± 4.5 mmol/l) predose to 159.4 ± 93.0 mg/dl (4.1 ± 2.4 mmol/l) at 12 months (p = 0.0245). Conclusion: This interim analysis suggests lomitapide is safe and effective in real-world clinical practice in Japan.

The Effect of PCSK9 Inhibitors on LDL-C Target Achievement in Patients with Homozygous Familial Hypercholesterolemia: A Retrospective Cohort Analysis

INTRODUCTION

Achieving target low-density lipoprotein-cholesterol (LDL-C) levels remains challenging when treating homozygous familial hypercholesterolemia (HoFH). Proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) are prescribed in addition to statins and ezetimibe, but patients' response varies and depends on residual low-density lipoprotein receptor (LDLR) function.

METHODS

A multicenter, retrospective observational analysis evaluated LDL-C target achievement in response to PCSK9i treatment in 28 patients with HoFH from the Middle East/North Africa region. Effect of genotype was investigated. Demographic and clinical information was retrospectively obtained from medical records. Patient response to PCSK9i treatment was assessed by calculating percentage changes in lipid levels from pre-PCSK9i treatment baseline to most recent follow-up visit where patients were recorded as receiving PCSK9i on top of standard of care lipid-lowering therapies (LLTs; i.e., statins/ezetimibe) and assessing European Atherosclerosis Society (EAS) target achievement up to January 31, 2022. Lowest LDL-C level while receiving PCSK9i was identified.

RESULTS

The cohort (n = 28) had a mean age (standard deviation; SD) of 22.8 (9.8) years (n = 28) and was 51% female (n = 27). Baseline LDL-C data were available in 24/28 (85.7%) patients (mean [SD] 14.0 [3.0] mmol/L). Median (interquartile range) duration of PCSK9i treatment was 12.0 months (4.0-19.1) months and mean (SD) % change in LDL-C after PCSK9i treatment was - 8.6% (12.1). LDL-C reduction from baseline was below 15% in 17/24 patients (70.8%). In the full cohort, mean (SD) minimum LDL-C during PCSK9i treatment was 11.9 (2.8; n = 28) mmol/L. No patient achieved EAS target LDL-C while receiving PCSK9i; genotype analysis suggested LDLR-null/null patients were most refractory to PCSK9i.

CONCLUSION

Response to PCSK9i was minimal in this cohort of patients with HoFH. No patients achieved EAS LDL-C targets, and most failed to reach the EAS-recommended 15% LDL-C reduction for PCSK9i therapy continuation. These results suggest additional LLTs are necessary to achieve LDL-C targets in HoFH.

Beyond statins: New pharmacological targets to decrease LDL-cholesterol and cardiovascular events

The pharmacological treatment of dyslipidemia, a major modifiable risk factor for developing atherosclerotic cardiovascular disease (ASCVD), remains a debated and controversial issue, not only in terms of the most appropriate therapeutic range for lipid levels, but also with regard to the optimal strategy and sequence approach (stepwise vs upstream therapy). Current treatment guidelines for the management of dyslipidemia focus on the intensity of low-density lipoprotein cholesterol (LDL-C) reduction, stratified according to risk for developing ASCVD. Beyond statins and ezetimibe, different medications targeting LDL-C have been recently approved by regulatory agencies with potential innovative mechanisms of action, including proprotein convertase subtilisin/kexin type 9 modulators (monoclonal antibodies such as evolocumab and alirocumab; small interfering RNA molecules such as inclisiran), ATP-citrate lyase inhibitors (bempedoic acid), angiopoietin-like 3 inhibitors (evinacumab), and microsomal triglyceride transfer protein inhibitors (lomitapide). An understanding of their pharmacological aspects, benefit-risk profile, including impact on hard cardiovascular endpoints beyond LDL-C reduction, and potential advantages from the patient perspective (e.g., adherence) - the focus of this evidence-based review - is crucial for practitioners across medical specialties to minimize therapeutic inertia and support clinical practice.

Advances in Treatment of Dyslipidemia

Dyslipidemias have emerged as prevalent disorders among patients, posing significant risks for the development and progression of cardiovascular diseases. These conditions are characterized by elevated levels of total cholesterol (TC), triglycerides (TGs), and low-density lipoprotein cholesterol (LDL-C). This review delves into the current treatment approach, focusing on equalizing these parameters while enhancing the overall quality of life for patients. Through an extensive analysis of clinical trials, we identify disorders that necessitate alternative treatment strategies, notably familial hypercholesterolemia. The primary objective of this review is to consolidate existing information concerning drugs with the potential to revolutionize dyslipidemia management significantly. Among these promising pharmaceuticals, we highlight alirocumab, bempedoic acid, antisense oligonucleotides, angiopoietin-like protein inhibitors, apolipoprotein C-III (APOC3) inhibitors, lomitapide, and cholesterol ester transfer protein (CETP) inhibitors. Our review demonstrates the pivotal roles played by each of these drugs in targeting specific parameters of lipid metabolism. We outline the future landscape of dyslipidemia treatment, envisaging a more tailored and effective therapeutic approach to address this widespread medical concern.

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.

Long-term hepatic safety of lomitapide in homozygous familial hypercholesterolaemia

INTRODUCTION

Lomitapide is a microsomal triglyceride transfer protein inhibitor for patients with homozygous familial hypercholesterolaemia. Due to its mechanism of action, potential hepatic effects of lomitapide are of clinical interest. This study aimed to determine the long-term hepatic safety of lomitapide.

METHODS

Data were aggregated from the pivotal phase 3 and extension phase clinical trial with lomitapide (median 5.1 years; serum total bilirubin, transaminases, cytokeratin-18 [CK-18] and enhanced liver fibrosis [ELF] score, fat-soluble vitamins and essential fatty acids), 8-year data from the Lomitapide Observational Worldwide Evaluation Registry (LOWER) and real-world evidence from a cohort of patients treated with lomitapide in Italy (hepatic elastography, and FIB-4 score for hepatic fibrosis).

RESULTS

In the phase 3 trial and the LOWER registry, any asymptomatic excursions in liver transaminase levels were not associated with elevations in bilirubin, and no Hy's law cases were detected in up to 8 years follow-up. There were no clinically relevant increases among hepatic biomarkers CK-18, CK-18 fragments or ELF score and fat-soluble vitamins and essential fatty acids remained above normal levels. In 34 patients treated in Italy with lomita pide for more than 9  years, elevations in hepatic fat were mild-to-moderate; hepatic stiffness remained normal, and the mean FIB-4 score remained below the fibrosis threshold value of 2.67.

CONCLUSIONS

These data indicate that the hepatic safety of lomitapide remains favourable with no clinically significant elevations in hepatic biomarkers and hepatic stiffness remained normal for more than 9 years follow-up. PHASE 3 TRIAL: NCT00730236; extension phase: NCT00943306; LOWER: NCT02135705.

Current Treatment Options in Homozygous Familial Hypercholesterolemia

Homozygous familial hypercholesterolemia (HoFH) is the rare form of familial hypercholesterolemia causing extremely high low-density lipoprotein cholesterol (LDL-C) levels, leading to atherosclerotic cardiovascular disease (ASCVD) in the first decades of life, if left untreated. Early diagnosis and effective lipid lowering therapy (LLT) are crucial for the prevention of early ASCVD in patients with HoFH. On-treatment LDL-C levels are the best predictor of survival. However, due to the absent or defective LDL-receptor activity, most individuals with HoFH are resistant to conventional LLT, that leads to LDL-C clearance by upregulating LDL-receptors. We are at the dawn of a new era of effective pharmacotherapies for HoFH patients, with new agents providing an LDL-receptor independent cholesterol reduction. In this context, the present review provides a summary of the currently available therapies and emerging therapeutic agents for the management of patients with HoFH, in light of recent evidence and guideline recommendations.

Efficacy and safety of lomitapide in familial chylomicronaemia syndrome

BACKGROUND AND AIMS

Familial chylomicronaemia syndrome (FCS) is a rare autosomal recessive disorder, resulting in elevated triglycerides (TGs), abdominal pain and pancreatitis. Treatment options are limited. Lomitapide, a microsomal triglyceride transfer protein inhibitor, is approved for the treatment of homozygous familial hypercholesterolaemia. Whether its therapeutic use may be extended to FCS remains unknown. The aim of this study was to evaluate the efficacy and safety of lomitapide in adult patients with FCS.

METHODS

The open-label, single-arm 'LOCHNES' study of lomitapide in FCS enrolled patients >18 years with genetically confirmed FCS, elevated fasting TG ≥ 750 mg/dL and history of pancreatitis. Patients were administered lomitapide to the maximum tolerated dose for 26 weeks. The primary endpoint was the percent change in TGs from baseline to Week 26.

RESULTS

Eighteen patients were enrolled with median baseline TG levels 1803.5 mg/dL (97.5% CI, 1452-2391 mg/dL). At Week 26, median fasting TGs were reduced to 305 mg/dL (97.5% CI 219-801 mg/dL; 70.5% reduction); median lomitapide dose was 35 mg/day; 13 patients achieved TGs ≤750 mg/dL. Adverse events were mild to moderate and mainly related to gastrointestinal tolerability. Liver imaging at baseline and Week 26 revealed hepatic fat increases from median 12.0%-32.5%, while median hepatic stiffness remained normal. No patient experienced acute pancreatitis or severe abdominal pain during lomitapide treatment.

CONCLUSIONS

Lomitapide is effective and well tolerated in reducing TGs in FCS patients with a history of pancreatitis. Larger studies are warranted to determine lomitapide effectiveness in FCS.

The Progression of Treatment for Refractory Hypercholesterolemia: Focus on the Prospect of Gene Therapy

Refractory hypercholesterolemia (RH), including homozygous familial hypercholesterolemia (HoFH) and compound heterozygous familial hypercholesterolemia, is characterized by high levels of low-density lipoprotein cholesterol (LDL-C) despite existing cholesterol-lowering methods at maximal tolerable doses. Patients with RH have early onset and higher risk of atherosclerotic cardiovascular disease (ASCVD) under insufficient treatment. Therefore, it is urgent to seek new therapies to maintain the blood lipids in refractory hyperlipidemia at normal levels. Currently, new cholesterol-lowering strategies are on the market, not only at the protein level [i.e., bempedoic acid (inhibiting ATP-citrate lyase), alirocumab and evolocumab (monoclonal antibodies against PCSK9), evinacumab (monoclonal antibody against ANGPTL3)] but also at the transcript level [i.e., mipomersen (antisense oligonucleotide inhibiting ApoB), inclisiran (siRNA targeting PCSK9)], providing more options for RH patients to achieve their lipid-lowering targets. More RNA-based therapies targeting RH-related genes have been designed for the treatment. However, for a proportion of patients, especially those with LDLR deficiency, the available treatments are still insufficient. More recently, emerging genome engineering based on CRISPR/Cas9 techniques, and advanced delivery technologies such as lentiviral vectors, adenoviral vectors, adeno-associated viral vectors, lipid nanoparticles, and exosomes are being rapidly developed and implemented as novel therapies for RH. Gene therapy targeting RH-related genes has been successfully conducted in cells, mice, and non-human primates with high efficacy in lipid lowering and good tolerability. Especially the new generation of genome editing technique, base editing, performed in vivo with ideal lipid-lowering effect and limited occurrence of unwanted results. Excitingly, a phase I/II clinical study of LDLR gene replacement has been recently completed in RH patients, likely to be employed in clinical practice in the future. Furthermore, new targets for cholesterol reduction such as REV-ERB, G protein-coupled receptor, Ubiquitin specific peptidase 20 are continually being developed. This narrative review updates recent advances in treatment for RH, summarizes related clinical trials and preclinical studies, especially on the prospect of gene therapy.

Advancements in the Treatment of Homozygous Familial Hypercholesterolemia

Homozygous familial hypercholesterolemia (HoFH) is a rare genetic disorder with extreme elevations of low-density lipoprotein cholesterol (LDL-C) leading to premature atherosclerotic cardiovascular disease (ASCVD) as early as in childhood. Management of HoFH centers around aggressive and adequate reduction of LDL-C levels to slow the trajectory of ASCVD development. Historically, lowering LDL-C levels in HoFH has been challenging because of both the markedly elevated LDL-C levels (often ＞400 mg/dL) and reduced response to treatment options, such as statins, for which the mechanism of action requires a functional LDL receptor. However, the treatment landscape for HoFH has rapidly progressed over the last decade. While statins and ezetimibe remain first-line treatment, patients often require addition of multiple therapies to achieve goal LDL-C levels. The PCSK9 inhibitors are an important recent addition to the available treatment options, along with lomitapide, bile acid sequestrants, and, possibly, bempedoic acid. Additionally, ANGPTL3 has emerged as an important therapeutic target, with evinacumab being the first available ANGPTL3 inhibitor on the market for the treatment of patients with HoFH. For patients who cannot achieve adequate LDL-C reduction, lipoprotein apheresis may be necessary, with the added benefit of reducing lipoprotein(a) levels that carries an added risk if also elevated in patients with HoFH. Finally, gene therapy and genome editing using CRISPR/Cas-9 are moving through clinical development and may dramatically alter the future landscape of treatment for HoFH.

Novel Pharmaceutical and Nutraceutical-Based Approaches for Cardiovascular Diseases Prevention Targeting Atherogenic Small Dense LDL

Compelling evidence supports the causative link between increased levels of low-density lipoprotein cholesterol (LDL-C) and atherosclerotic cardiovascular disease (CVD) development. For that reason, the principal aim of primary and secondary cardiovascular prevention is to reach and sustain recommended LDL-C goals. Although there is a considerable body of evidence that shows that lowering LDL-C levels is directly associated with CVD risk reduction, recent data shows that the majority of patients across Europe cannot achieve their LDL-C targets. In attempting to address this matter, a new overarching concept of a lipid-lowering approach, comprising of even more intensive, much earlier and longer intervention to reduce LDL-C level, was recently proposed for high-risk patients. Another important concern is the residual risk for recurrent cardiovascular events despite optimal LDL-C reduction, suggesting that novel lipid biomarkers should also be considered as potential therapeutic targets. Among them, small dense LDL particles (sdLDL) seem to have the most significant potential for therapeutic modulation. This paper discusses the potential of traditional and emerging lipid-lowering approaches for cardiovascular prevention by targeting sdLDL particles.

A Case Series Assessing the Effects of Lomitapide on Carotid Intima-Media Thickness in Adult Patients with Homozygous Familial Hypercholesterolaemia in a Real-World Setting

INTRODUCTION

Homozygous familial hypercholesterolaemia (HoFH) is characterised by extremely elevated levels of low-density lipoprotein cholesterol (LDL-C) and results from multiple mutations in genes affecting the LDL receptor pathway. Patients are at risk of premature atherosclerotic cardiovascular disease (ASCVD) and premature death. Lomitapide is a microsomal triglyceride transfer protein inhibitor developed to treat HoFH, but cardiovascular outcome data are lacking.

METHODS

We evaluated detailed data from five HoFH patients and one patient with heterozygous FH (HeFH) and a very severe phenotype. We also analysed confirmatory data from a further 8 HoFH cases. In total, we analysed data from patients in seven global centres in six countries who were all treated with lomitapide with long-term follow-up. Carotid intima-media thickness (CIMT) imaging was recorded on an ad hoc basis to monitor ASCVD in HoFH.

RESULTS

Lomitapide resulted in marked decreases in LDL-C of 56.8-93.9% [77.7-93.9% in the 6 initial cases (mean nadir 64.8 ± 30.1 mg/dL); 56.8-86.0% in the 8 confirmatory cases (mean nadir 131.4 ± 38.2 mg/dL)]. CIMT regressed in 50% of cases (mean follow-up 5.0 ± 3.1 years in initial six cases, and 4.4 ± 1.4 years in confirmatory cases). In the remaining patients, CIMT showed little further change. In patients where assessments of plaque area were available, regression or stabilisation in CIMT was accompanied by clinically significant regression of plaque area.

CONCLUSIONS

Lomitapide reduces LDL-C levels in patients with HoFH and severe LDL-C phenotypes, and results in stabilisation and/or regression of CIMT, which is an established marker of ASCVD risk. Additional data are needed to determine if this confers a survival benefit in these very high-risk patients.

EFFICACY AND SAFETY OF LOMITAPIDE IN HOMOZYGOUS FAMILIAL HYPERCHOLESTEROLEMIA: THE PAN-EUROPEAN RETROSPECTIVE OBSERVATIONAL STUDY

BACKGROUND

Lomitapide is a lipid-lowering agent indicated as adjunct therapy for adult HoFH.

OBJECTIVES

This study evaluated the medium-term effectiveness and safety of lomitapide in a large cohort of HoFH patients in Europe.

METHODS

In a multicenter retrospective, observational study including 75 HoFH patients treated with lomitapide in a real-world clinical setting from 9 European countries, LDL-C changes, adverse events (AEs) as well as major adverse cardiovascular events (MACE) were assessed.

RESULTS

After a median 19 months (IQR 11-41 months) of treatment with a mean dosage of 20 mg of lomitapide. LDL-C decreased by 60%, from baseline 280.5 mg/dL (191.8-405.0 mg/dl) to 121.6 mg/dl (61.0-190.5 mg/dl). At the last visit, 32.0% of patients achieved LDL-C < 100mg/dL and 18.7% <70 mg/dL. At baseline, 38 HoFH patients were receiving LDL apheresis (LA), but after initiation of lomitapide 36.8% of patients discontinued LA. During follow-up, lomitapide was permanently interrupted in 13% of patients. Gastrointestinal (GI) AEs occurred in 40% and liver transaminases increased (3-5 x ULN) in 13% of patients. Among patients with liver ultrasound evaluation (n = 45), a modest increase in hepatic steatosis was noted during treatment; however liver stiffness measured by elastography in 30 of them remained within the normal range. Among HoFH patients exposed to lomitapide for at least 2 years, MACE incident rate was 7.4 per 1000 person-years in the 2 years after as compared to 21.2 per 1000 person-years before treatment with lomitapide.

CONCLUSIONS

In this medium-term real-world experience, lomitapide proved to be very effective in reducing LDL-C in HoFH. GI AEs were common, but liver safety was reassuring with no sign of increased risk of liver fibrosis. A signal of cardiovascular protection was also observed.

New Frontiers in the Treatment of Homozygous Familial Hypercholesterolemia

Homozygous familial hypercholesterolemia (HoFH) is a rare genetic disorder. The most common cause is a mutation in both alleles of the gene encoding for the low-density lipoprotein (LDL) receptor, although other causative mutations have been identified. Complications of atherosclerotic cardiovascular disease are common in these patients; therefore, reducing the elevated LDL-cholesterol burden is critical in their management. Conventionally, this is achieved by patients initiating lipid-lowering therapy, but this can present challenges in clinical practice. Fortunately, novel therapeutic strategies have enabled promising innovations in HoFH treatment. This review highlights recent and ongoing studies examining new therapeutic options for patients with HoFH.

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.

Lomitapide does not alter PCSK9 and Lp(a) levels in homozygous familial hypercholesterolemia patients: Analysis on cytokines and lipid profile

Lomitapide, a drug for the treatment of homozygous familial hypercholesterolemia patients, reduced total and LDL cholesterol but no significant changes were observed on PCSK9 and Lp(a) plasma levels. Some changes of inflammatory mediators were also observed, including hsCRP, which may suggest an anti-inflammatory effect.

Rare Treatments for Rare Dyslipidemias: New Perspectives in the Treatment of Homozygous Familial Hypercholesterolemia (HoFH) and Familial Chylomicronemia Syndrome (FCS)

Purpose of Review

This review aims to summarize the most recent published literature concerning lomitapide and volanesorsen that are approved for the use in HoFH and FCS patients, respectively. Moreover, it will briefly revise the published evidence on novel, non-approved treatments that are under evaluation for the management of these rare forms of dyslipidemias

Recent Findings

The definition of rare dyslipidemias identifies a large number of severe disorders of lipid metabolism of genetic origin. Among them were homozygous familial hypercholesterolemia (HoFH) (OMIM #143890) and familial chylomicronemia syndrome (FCS) (OMIM #238600), which are characterized by a markedly impaired cholesterol- and triglyceride-containing lipoproteins metabolism. They are being particularly associated with poor health outcomes and quality of life. Considering the severity of these diseases, common lipid-lowering drugs are often ineffective or do not allow to achieve the recommended lipid targets to prevent the development of complications. Nowadays, several new drugs have been found to effectively treat HoFH and FCS with an acceptable safety profile.

Summary

Treating patients with HoFH and FCS remains very challenging. However, novel treatment options are emerging and might be considered in addition to conventional therapy for managing these diseases. These novel drugs will possibly change the natural history of these two rare and life-threatening diseases.

Pharmacogenomics Variability of Lipid-Lowering Therapies in Familial Hypercholesterolemia

The exponential expansion of genomic data coupled with the lack of appropriate clinical categorization of the variants is posing a major challenge to conventional medications for many common and rare diseases. To narrow this gap and achieve the goals of personalized medicine, a collaborative effort should be made to characterize the genomic variants functionally and clinically with a massive global genomic sequencing of "healthy" subjects from several ethnicities. Familial-based clustered diseases with homogenous genetic backgrounds are amongst the most beneficial tools to help address this challenge. This review will discuss the diagnosis, management, and clinical monitoring of familial hypercholesterolemia patients from a wide angle to cover both the genetic mutations underlying the phenotype, and the pharmacogenomic traits unveiled by the conventional and novel therapeutic approaches. Achieving a drug-related interactive genomic map will potentially benefit populations at risk across the globe who suffer from dyslipidemia.

Persistent hypercholesterolemia in child with homozygous autosomal recessive hypercholesterolemia: A decade of lipid management

Autosomal recessive hypercholesterolemia (ARH) is a rare form of genetic hypercholesterolemia caused by mutations in low density lipoprotein receptor adaptor protein 1 (LDLRAP1). The proband first presented with linear eruptive xanthomas over her ankles, knees and elbows, with low density lipoprotein cholesterol (LDL-C) of 16.0 mmol/L (618.7 mg/dL), at 2.5 years old. Next generation sequencing revealed a novel homozygous mutation in LDLRAP1 exon 5 (c.466delG). In the first year, drug regimens of either cholestyramine or simvastatin, reduced her LDL-C to 10.5 mmol/L (406 mg/dL) and 11.7 mmol/L (452.4 mg/dL), respectively. Combination simvastatin and ezetimibe was the mainstay of therapy from age 5 - 10 years. Her lowest achieved LDL-C was 6.3 mmol/L (243.6 mg/dL). Switching to atorvastatin did not lead to further reduction. Carotid intima-media thickness was 0.47 mm (> 97^th percentile) and 0.32 mm (75 - 95^th percentile) at ages 8 years and 11 years, respectively. Addition of monthly injections of evolocumab for 3 months, led to an increase in LDL-C, from 7.0 mmol/L (270.7 mg/dL) to a range of [(8.4 - 9.1) mmol/L or (324.8 - 351.9) mg/dL]. In this report, a decade-long lipid management is described in a patient with ARH. Residual activity of LDLRAP1 is a likely determinant of her response. Clinical management remains sub-optimal and options for the paediatric population are limited. Novel classes of cholesterol-lowering medications are needed for this ultra-rare and severe hypercholesterolemia.

[Management of dyslipidaemias: The New 2019 ESC/EAS-Guideline]

The updated guidelines for the management of dyslipidaemias 2019 sticks to the concept of individual risk-based intervention strategies, but intensifies LDL-C goals. Next to the established SCORE system non-invasive imaging techniques such as coronary CT or ultrasound of carotid or femoral arteries are now recommended for improved risk stratification. Screening for lipoprotein(a) identifies persons at higher cardiovascular risk. Non-statin trials with ezetimibe and PSCK9-inhibitors demonstrated further relative risk reduction for cardiovascular events. Cardiovascular risk reduction depends on the absolute lowering of LDL-C, duration of therapy and the individual cardiovascular risk. For patients at very high risk the new LDL-C goal is < 1.4 mmol/l (55 mg/dl) and reduction of ≥ 50 % from baseline. The overall aim is to reduce "cholesterol life years".

Low cholesterol syndrome and drug development

PURPOSE OF REVIEW

Low cholesterol syndromes were considered curiosities. The present article reviews some hypolipidaemic disorders and the drugs developed from the insights they provided.

RECENT FINDINGS

Abetalipopoproteinaemia and hypobetalipoproteinaemia are associated with low cholesterol concentrations and caused by mutations in apolipoprotein (apo) B or microsomal transfer protein. This led to the development of mipomersen and lomitapide which are used to treat homozygous familial hypercholesterolaemia. Mutations in proprotein convertase subtilisin kexin-9 (PCSK9) can cause either high or low cholesterol. Loss of function PCSK9 mutations prompted the development of antibody therapies to PCSK9 which are now widely used to treat hypercholesterolaemia. Mutations in apolipoprotein C-3 and angiopoietin-like protein 3 (ANGPTL3) cause hypolipoproteinaemia and reduced triglycerides. Antisense therapies to apolipoprotein C-3 and antibodies to ANGPTL3 are in development to treat familial chylomicronaemia syndrome. Activating mutations in apoA-1 result in hyper-functioning high-density lipoprotein (HDL) and suggest that modifying HDL turnover may reduce cardiovascular disease (CVD) risk.

SUMMARY

Orphan lipid disorders have provided insights into mechanisms involved in lowering cholesterol levels and the potential safety and efficacy of interventional processes. They have been not only enabled development of drugs to treat rare lipid disorders but also those finding wider use in general lowering of CVD risk.

Therapeutic Options for Homozygous Familial Hypercholesterolemia: The Role of Lomitapide

Background:

Lomitapide (Juxtapid® in US and Lojuxta® in Europe) is the first developed inhibitor of the Microsomal Triglyceride Transfer Protein (MTP) approved as a novel drug for the management of Homozygous Familial Hypercholesterolemia (HoFH). It acts by binding directly and selectively to MTP thus decreasing the assembly and secretion of the apo-B containing lipoproteins both in the liver and in the intestine.

Aims:

The present review aims at summarizing the recent knowledge on lomitapide in the management of HoFH.

Results:

The efficacy and safety of lomitapide have been evaluated in several trials and it has been shown a reduction of the plasma levels of Low-Density Lipoprotein Cholesterol (LDL-C) by an average of more than 50%. Although the most common side effects are gastrointestinal and liver events, lomitapide presents generally with a good tolerability and satisfactory patients compliance. Recently, in Europe, to evaluate the long-term safety and efficacy of lomitapide, the LOWER registry (ClinicalTrials.gov Identifier: NCT02135705) has been established in order to acquire informations on HoFH lomitapidetreated patients from “real life” clinical practice.

:

Furthermore, the observation that lomitapide decreases triglyceride levels may be considered for patients affected by severe forms of hypertriglyceridemia who undergo recurrent episodes of pancreatitis and are poor responders to conventional treatment.

Conclusion:

Lomitapide represents an innovative and efficacious drug for the treatment of HoFH. Longterm safety data, treatment of pediatric and pregnant HoFH patients and management of severe hypertriglyceridemia still require further investigations.

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.

Homozygous familial hypercholesterolemia: what treatments are on the horizon?

PURPOSE OF REVIEW

Homozygous familial hypercholesterolemia (HoFH) is a rare disorder associated with early atherosclerotic disease due to impairment of the LDL receptor (LDLR) pathway. Because of their molecular defect, current treatment options have limited success in bringing HoFH patient to LDL-C target and morbidity and mortality remain high. We review current and upcoming therapies directed at HoFH, including gene therapy.

RECENT FINDINGS

Recent real-world studies have confirmed the strength in lomitapide as a treatment adjunct to statins and other lipid-lowering therapies in HoFH patients. The approval of proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor monoclonal antibodies has also been a welcome addition to the treatment armamentarium offering an additional average reduction in LDL-C levels of 24% when added to background lipid-lowering therapies in this population. Although achieving adequate LDL-C levels in this population is difficult, there are several therapies on the horizon that may help more patients reach goal. Evinacumab, a monoclonal antibody against ANGPTL3, has been shown to substantially reduce LDL-C of an average of 49%, independently of residual LDLR activity. RNA interference targeting PCSK9 and ANGPTL3 shows promise in clinical trials. Adeno-associated virus-mediated gene transfer and gene editing techniques are in early clinical and preclinical development.

SUMMARY

LDL-C lowering in HoFH patients remains very challenging. However, novel treatment options are emerging. Upcoming therapies directed at PCSK9 and ANPTL3 may offer additional LDL-C reduction, to help patients achieve adequate LDL-C levels. Gene therapy and gene editing techniques, if proven effective, may offer a unique opportunity to treat patients with a one-time treatment.

Autosomal recessive hypercholesterolemia: update for 2020

PURPOSE OF REVIEW

This review summarizes the current knowledge regarding autosomal recessive hypercholesterolemia (ARH) and provides new insight into the natural history and therapeutic management of this lipid disorder.

RECENT FINDINGS

Novel homozygous and compound heterozygous ARH-causing mutations have been reported in the literature, to date. The long-term follow-up of a cohort of ARH patients demonstrated that, despite intensive treatment with conventional lipid-lowering therapies, their low-density lipoprotein (LDL) cholesterol levels remain far from target and this translates into a poor cardiovascular prognosis. ARH is also associated with increased risk of developing aortic valve stenosis. However, lomitapide, a microsomal triglyceride transfers protein inhibitor, may represent a new opportunity for the effective treatment of ARH.

SUMMARY

ARH is an ultrarare disorder of LDL metabolism caused by mutations in the LDLRAP1 gene. It is inherited as a recessive trait and causative mutations, though heterogeneous, are all predicted to be loss-of-function. Recent investigations have demonstrated that ARH can be considered a phenocopy of homozygous familial hypercholesterolemia, where the risk of atherosclerotic cardiovascular diseases and aortic valve stenosis remains elevated despite conventional therapies. The combination of lomitapide with the conventional LDL-C-lowering medications appears to be a promising approach to treat this condition.

Homozygous familial hypercholesterolemia in a young woman with dual gene mutations of low-density lipoprotein receptor and proprotein convertase subtilisin/kexin type 9

A 28-year-old woman with a rare combination of homozygous LDLR and heterozygous PCSK9 mutations had a phenotype consistent with homozygous familial hypercholesterolemia. She reported a clinical history of coronary and extracoronary atherosclerosis treated with 3 coronary stenting procedures, one coronary bypass, and aortic and mitral valve replacements. Because the patient refused lipoprotein apheresis, lipid-lowering therapy with statins, ezetimibe, and evolocumab was started. The desired low-density lipoprotein cholesterol target was not achieved. Dose-escalated lomitapide therapy (up to 30 mg/d) was added, enabling achievement of low-density lipoprotein cholesterol levels of 45 mg/dL during 24 months' follow-up. During this period, no cardiovascular events or clinical evidence of side effects occurred. In this case, lomitapide has been used in combination with maximum-tolerated statin therapy to successfully treat a patient with a rare combination of mutations in both LDLR and PCSK9 genes.

Lomitapide treatment in a female with homozygous familial hypercholesterolaemia: a case report

Background

Homozygous familial hypercholesterolaemia (FH) is an autosomal-dominant inherited disease presenting with highly elevated low-density lipoprotein cholesterol (LDL-C) levels. Untreated, the patient can develop atherosclerosis and cardiovascular disease already in adolescence. Treatment with statins and ezetimibe is usually not sufficient and LDL apheresis is often required. Lomitapide, an inhibitor of the microsomal triglyceride transfer protein, reduces LDL-C and triglyceride levels and can be used alone or in combination with other therapies in homozygous FH. However, experience with this agent is still limited.

Case summary

We present a young female who was diagnosed with homozygous FH at 6 years of age. She shows a complete lack of normal LDL receptor activity and no cholesterol-lowering effect from statins. The patient was treated with LDL apheresis from 7 years of age. When LDL apheresis treatment extended to twice a week, she began to experience adverse effects, including catheter-related complications, infections, and hospital admissions. When lomitapide treatment was initiated, the frequency of apheresis reduced, the LDL-C levels improved and she has not had any further hospital admissions since. Initially, she suffered from gastrointestinal disturbances. However, after 3 years of treatment with lomitapide 20 mg/day, the patient has not experienced any adverse effects.

Discussion

In this female with homozygous FH adding lomitapide treatment to LDL apheresis has contributed to improved LDL-C levels, a reduction in LDL apheresis sessions and enhanced quality of life. No adverse effects have been reported. These findings suggest that lomitapide can be a drug of choice in patients with homozygous FH.

A Real-World Experience of Clinical, Biochemical and Genetic Assessment of Patients with Homozygous Familial Hypercholesterolemia

Homozygous familial hypercholesterolemia (HoFH), the severest form of familial hypercholesterolemia (FH), is characterized by very high LDL-cholesterol levels and a high frequency of coronary heart disease. The disease is caused by the presence of either a pathogenic variant at homozygous status or of two pathogenic variants at compound heterozygous status in the LDLR, APOB, PCSK9 genes. We retrospectively analyzed data of 23 HoFH patients (four children and 19 adults) identified during the genetic screening of 724 FH patients. Genetic screening was performed by sequencing FH causative genes and identifying large rearrangements of LDLR. Among the HoFH patients, four out of 23 (17.4%) were true homozygotes, whereas 19 out of 23 (82.6%) were compound heterozygotes for variants in the LDLR gene. Basal LDL-cholesterol was 12.9 ± 2.9 mmol/L. LDL-cholesterol levels decreased to 7.2 ± 1.8 mmol/L when treated with statin/ezetimibe and to 5.1 ± 3.1 mmol/L with anti-PCSK9 antibodies. Homozygous patients showed higher basal LDL-cholesterol and a poorer response to therapy compared with compound heterozygotes. Since 19 unrelated patients were identified in the Campania region (6,000,000 inhabitants) in southern Italy, the regional prevalence of HoFH was estimated to be at least 1:320,000. In conclusion, our results revealed a worse phenotype for homozygotes compared with compound heterozygotes, thereby highlighting the role of genetic screening in differentiating one genetic status from the other.

Lomitapide and Mipomersen-Inhibiting Microsomal Triglyceride Transfer Protein (MTP) and apoB100 Synthesis

PURPOSE OF REVIEW

The goal of this review is to evaluate the role of inhibiting the synthesis of lipoproteins when there is no or little residual LDL-receptor function as in patients with homozygous familial hypercholesterolaemia. Lomitapide is administered orally once a day while mipomersen is given by subcutaneous injection once a week. Lomitapide inhibits microsomal triglyceride transfer protein while mipomersen is an antisense oligonucleotide directed against apoB100.

RECENT FINDINGS

The pivotal registration trials for lomitapide and mipomersen were published in 2013 and 2010, respectively. More recently published data from extension trials and cohort studies provides additional information on long-term safety and efficacy. The mean LDL cholesterol reduction was 50% with lomitapide in its single-arm open-label registration trial. Mipomersen reduced LDL cholesterol by approximately 25% in its double-blind, placebo-controlled registration study. Both lomitapide and mipomersen therapy are associated with variable increases in hepatic fat content. The long-term safety of increased hepatic fat content in patients receiving these therapies is uncertain and requires further study. Both drugs may cause elevated transaminase in some patients, but no cases of severe liver injury have been reported. Lomitapide may also cause gastrointestinal discomfort and diarrhoea, especially if patients consume high-fat meals and patients are advised to follow a low-fat diet supplemented with essential fatty acids and fat-soluble vitamins. Mipomersen may cause injection-site and influenza-like reactions. The effect of lomitapide and mipomersen on cardiovascular outcomes has not been studied, but circumstantial evidence suggests that the LDL cholesterol lowering achieved with these two agents may reduce cardiovascular event rates.

New Therapeutic Approaches for Familial Hypercholesterolemia

Familial hypercholesterolemia (FH) is a common genetic condition characterized by elevated plasma levels of low-density lipoprotein cholesterol (LDL-C), premature atherosclerotic cardiovascular disease, and considerable unmet medical need with conventional LDL-C-lowering therapies. Between 2012 and 2015, the US Food and Drug Administration approved four novel LDL-C-lowering agents for use in patients with FH based on the pronounced LDL-C-lowering efficacy of these medicines. We review the four novel approved agents, as well as promising LDL-C-lowering agents in clinical development, with a focus on their mechanism of action, efficacy in FH cohorts, and safety.

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.

Lomitapide: a review of its clinical use, efficacy, and tolerability

Lomitapide is an inhibitor of MTP, an enzyme located in the endoplasmic reticulum of hepatocytes and enterocytes. This enzyme is responsible for the synthesis of very low-density lipoproteins in the liver and chylomicrons in the intestine. Lomitapide has been approved by the US Food and Drug Administration, European Medicines Agency, and other regulatory agencies for the treatment of hypercholesterolemia in adult patients with homozygous familial hypercholesterolemia. Clinical trials have shown that lomitapide reduces low-density-lipoprotein cholesterol levels by around 40% in homozygous familial hypercholesterolemia patients on treatment with statins with or without low-density-lipoprotein apheresis, with an acceptable safety and tolerance profile. The most common adverse events are gastrointestinal symptoms that decrease in frequency with long-term treatment, and the increase in liver fat remains stable. This review analyzes the clinical use, efficacy, and tolerability of lomitapide.

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.

Achievement of low density lipoprotein (LDL) cholesterol targets in primary and secondary prevention: Analysis of a large real practice database in Italy

BACKGROUND AND AIMS

Target and intensity of low-density lipoprotein cholesterol (LDL-C) lowering therapy should be tailored according to the individual global cardiovascular (CV) risk. We aimed at retrospectively evaluating real-life LDL-C goal attainment and predictive factors for predefined LDL-C therapeutic goals both in primary and secondary prevention.

METHODS

We collected data from a large cohort of outpatients aged 40-65 years, followed by general practitioners, cardiologists and diabetologists in Italy. All data were centrally analysed for global CV risk assessment and rates of control of major CV risk factors, including LDL-C. Study population was stratified according to the presence or absence of previous CV events, including coronary artery disease (CAD), peripheral artery disease (PAD) or stroke/TIA. CV risk profile characterization was based on the European SCORE. Predefined therapeutic goals were set according to the European guidelines on dyslipidaemia: LDL-C levels <70 mg/dl for very high CV risk patients in primary prevention and for those in secondary prevention; <100 mg/dl LDL-C levels for high CV risk patients in primary prevention. Logistic regression analysis with clinical covariates was used to identify predictive factors for achieving these goals; lipid lowering therapy entered in the analysis as continuous (model 1) or categorical variable (model 2).

RESULTS

We included 4,142 outpatients (43,7% female, age 58.0 ± 5.2 years, BMI 28.5 ± 5.0 kg/m²) among whom 2,964 (71.6%) in primary and 1,178 (28.4%) in secondary prevention. In primary prevention, none of the patients at very high CV risk had LDL-C <70 mg/dl and 8.9% of patients at high CV risk showed LDL-C <100 mg/dl. Only 5.8% of patients in secondary prevention had LDL-C levels <70 mg/dl, specifically 6.5% of patients with CAD, 2.6% of patients with PAD and 4.7% of patients with CVD (p < 0.001). Beyond diabetes and lipid lowering therapy, high risk SCORE estimation resulted a strong and independent predictor for the lack of achieving all predefined therapeutic targets, including LDL-C <100 mg/dl [OR: 0.806 (0.751-0.865)); p < 0.001], and LDL-C <70 mg/dl [OR: 0.712 (0-576-0.880); p = 0.002], in primary prevention.

CONCLUSIONS

Despite high or very high SCORE risk and use of lipid lowering therapies, we observed poor achievement of LDL-C targets in this large cohort of outpatients followed in a setting of real practice in Italy.