Target achievement and cardiovascular event rates with Lomitapide in homozygous Familial Hypercholesterolaemia

Background Homozygous familial hypercholesterolaemia (HoFH) is characterized by a markedly increased risk of premature cardiovascular (CV) events and cardiac death. Lomitapide reduces low-density lipoprotein cholesterol (LDL-C) levels; however, the probable impact on LDL-C goals and CV events is unknown. Methods We used data collected in the first 26 weeks of the lomitapide pivotal phase 3 study (NCT00730236) to evaluate achievement of European Atherosclerosis Society (EAS) LDL-C targets. We used publicly available data reporting major adverse CV events (MACE) rates from other cohorts of HoFH patients to compare event rates for an equivalent number of patient years of exposure (98) in the lomitapide extension trial (NCT00943306). Results Twenty-nine patients were included in the phase 3 study. During the first 26 weeks, 15 (51%) and eight (28%) reached LDL-C targets of 100 mg/dL and 70 mg/dL, respectively, at least once. Fourteen (74%) and 11 (58%) of the 19 patients who remained in the extension study after week 126 reached LDL-C targets of 100 mg/dL and 70 mg/dL at least once during the entire study period. Only two MACE were reported in the lomitapide trials (one cardiac death and one coronary artery bypass graft (CABG)) – equivalent to 1.7 events per 1000 patient months of treatment. MACE rates were 21.7, 9.5 and 1.8 per 1000 patient-months respectively in cohorts of HoFH patients pre- and post-mipomersen, and receiving evolocumab. On treatment LDL-C levels were 166, 331 and 286 mg/dL for lomitapide, mipomersen and evolocumab, respectively. Conclusions Approximately three quarters and half of patients who took lomitapide for at least 2 years reached LDL-C goals of 100 mg/dL and 70 mg/dL, respectively. There were fewer major CV events per 1000 patient months of treatment in patients taking lomitapide, mipomersen or evolocumab than reported in the mipomersen cohort prior to starting mipomersen. These results support the hypothesis that novel lipid-lowering therapies may reduce CV events in HoFH patients by lowering LDL-C further. Trial registration NCT00730236 (registered 8 Aug 2008) and NCT00943306 (registered 22 July 2009)

Microsomal Triglyceride Transfer Protein Transfers and Determines Plasma Concentrations of Ceramide and Sphingomyelin but Not Glycosylceramide

Sphingolipids, a large family of bioactive lipids, are implicated in stress responses, differentiation, proliferation, apoptosis, and other physiological processes. Aberrant plasma levels of sphingolipids contribute to metabolic disease, atherosclerosis, and insulin resistance. They are fairly evenly distributed in high density and apoB-containing lipoproteins (B-lps). Mechanisms involved in the transport of sphingolipids to the plasma are unknown. Here, we investigated the role of microsomal triglyceride transfer protein (MTP), required for B-lp assembly and secretion, in sphingolipid transport to the plasma. Abetalipoproteinemia patients with deleterious mutations in MTP and absence of B-lps had significantly lower plasma ceramide and sphingomyelin but normal hexosylceramide, lactosylceramide, and different sphingosines compared with unaffected controls. Furthermore, similar differential effects on plasma sphingolipids were seen in liver- and intestine-specific MTP knock-out (L,I-Mttp(-/-)) mice, suggesting that MTP specifically plays a role in the regulation of plasma ceramide and sphingomyelin. We hypothesized that MTP deficiency may affect either their synthesis or secretion. MTP deficiency had no effect on ceramide and sphingomyelin synthesis but reduced secretion from primary hepatocytes and hepatoma cells. Therefore, MTP is involved in ceramide and sphingomyelin secretion but not in their synthesis. We also found that MTP transferred these lipids between vesicles in vitro. Therefore, we propose that MTP might regulate plasma ceramide and sphingomyelin levels by transferring these lipids to B-lps in the liver and intestine and facilitating their secretion

Infusion of Reconstituted High-Density Lipoprotein, CSL112, in Patients With Atherosclerosis: Safety and Pharmacokinetic Results From a Phase 2a Randomized Clinical Trial

Background CSL112 is a new formulation of human apolipoprotein A‐I (apoA‐I) being developed to reduce cardiovascular events following acute coronary syndrome. This phase 2a, randomized, double‐blind, multicenter, dose‐ranging trial represents the first clinical investigation to assess the safety and pharmacokinetics/pharmacodynamics of a CSL112 infusion among patients with stable atherosclerotic disease. Methods and Results Patients were randomized to single ascending doses of CSL112 (1.7, 3.4, or 6.8 g) or placebo, administered over a 2‐hour period. Primary safety assessments consisted of alanine aminotransferase or aspartate aminotransferase elevations \u3e3× upper limits of normal and study drug–related adverse events. Pharmacokinetic/pharmacodynamic assessments included apoA‐I plasma concentration and measures of the ability of serum to promote cholesterol efflux from cells ex vivo. Of 45 patients randomized, 7, 12, and 14 received 1.7‐, 3.4‐, and 6.8‐g CSL112, respectively, and 11 received placebo. There were no clinically significant elevations (\u3e3× upper limit of normal) in alanine aminotransferase or aspartate aminotransferase. Adverse events were nonserious and mild and occurred in 5 (71%), 5 (41%), and 6 (43%) patients in the CSL112 1.7‐, 3.4‐, and 6.8‐g groups, respectively, compared with 3 (27%) placebo patients. The imbalance in adverse events was attributable to vessel puncture/infusion‐site bruising. CSL112 resulted in rapid (Tmax≈2 hours) and dose‐dependent increases in apoA‐I (145% increase in the 6.8‐g group) and total cholesterol efflux (up to 3.1‐fold higher than placebo) (P\u3c0.001). Conclusions CSL112 infusion was well tolerated in patients with stable atherosclerotic disease. CSL112 immediately raised apoA‐I levels and caused a rapid and marked increase in the capacity of serum to efflux cholesterol. This potential novel approach for the treatment of atherosclerosis warrants further investigation. Clinical Trial Registration URL: http://www.ClinicalTrials.gov. Unique identifier: NCT01499420

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) &gt;10 mmol/L (&gt;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.</p

Contemporary Homozygous Familial Hypercholesterolemia in the United States: Insights From the CASCADE FH Registry

Erratum in: J Am Heart Assoc. 2023 Jun 6;12(11):e027706. doi: 10.1161/JAHA.122.027706. Epub 2023 Jun 1.Free PMC article: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10227232/Background: Homozygous familial hypercholesterolemia (HoFH) is a rare, treatment-resistant disorder characterized by earlyonset atherosclerotic and aortic valvular cardiovascular disease if left untreated. Contemporary information on HoFH in the United States is lacking, and the extent of underdiagnosis and undertreatment is uncertain. Methods and Results: Data were analyzed from 67 children and adults with clinically diagnosed HoFH from the CASCADE (Cascade Screening for Awareness and Detection) FH Registry. Genetic diagnosis was confirmed in 43 patients. We used the clinical characteristics of genetically confirmed patients with HoFH to query the Family Heart Database, a US anonymized payer health database, to estimate the number of patients with similar lipid profiles in a “real-world” setting. Untreated lowdensity lipoprotein cholesterol levels were lower in adults than children (533 versus 776mg/dL; P=0.001). At enrollment, atherosclerotic cardiovascular disease and supravalvular and aortic valve stenosis were present in 78.4% and 43.8% and 25.5% and 18.8% of adults and children, respectively. At most recent follow-up, despite multiple lipid-lowering treatment, low-density lipoprotein cholesterol goals were achieved in only a minority of adults and children. Query of the Family Heart Database identified 277 individuals with profiles similar to patients with genetically confirmed HoFH. Advanced lipid-lowering treatments were prescribed for 18%; 40% were on no lipid-lowering treatment; atherosclerotic cardiovascular disease was reported in 20%; familial hypercholesterolemia diagnosis was uncommon. Conclusions: Only patients with the most severe HoFH phenotypes are diagnosed early. HoFH remains challenging to treat. Results from the Family Heart Database indicate HoFH is systemically underdiagnosed and undertreated. Earlier screening, aggressive lipid-lowering treatments, and guideline implementation are required to reduce disease burden in HoFH.Dr Martin is supported by grants/contracts from the American Heart Association (20SFRN35380046, 20SFRN35490003, 878924, and 882415), Patient‐Centered Outcomes Research Institute (PCORI) (ME‐2019C1‐15328), National Institutes of Health (NIH) (R01AG071032 and P01 HL108800), the David and June Trone Family Foundation, Pollin Digital Health Innovation Fund, and Sandra and Larry Small; Dr Knowles is supported by the NIH through grants P30 DK116074 (to the Stanford Diabetes Research Center), R01 DK116750, R01 DK120565, and R01 DK106236; and by a grant from the Bilateral Science Foundation. Dr Linton is supported by NIH grants P01HL116263, HL148137, HL159487, and HL146134.info:eu-repo/semantics/publishedVersio

Contemporary Homozygous Familial Hypercholesterolemia in the United States: Insights From the CASCADE FH Registry

Background Homozygous familial hypercholesterolemia (HoFH) is a rare, treatment‐resistant disorder characterized by early‐onset atherosclerotic and aortic valvular cardiovascular disease if left untreated. Contemporary information on HoFH in the United States is lacking, and the extent of underdiagnosis and undertreatment is uncertain. Methods and Results Data were analyzed from 67 children and adults with clinically diagnosed HoFH from the CASCADE (Cascade Screening for Awareness and Detection) FH Registry. Genetic diagnosis was confirmed in 43 patients. We used the clinical characteristics of genetically confirmed patients with HoFH to query the Family Heart Database, a US anonymized payer health database, to estimate the number of patients with similar lipid profiles in a “real‐world” setting. Untreated low‐density lipoprotein cholesterol levels were lower in adults than children (533 versus 776 mg/dL; P=0.001). At enrollment, atherosclerotic cardiovascular disease and supravalvular and aortic valve stenosis were present in 78.4% and 43.8% and 25.5% and 18.8% of adults and children, respectively. At most recent follow‐up, despite multiple lipid‐lowering treatment, low‐density lipoprotein cholesterol goals were achieved in only a minority of adults and children. Query of the Family Heart Database identified 277 individuals with profiles similar to patients with genetically confirmed HoFH. Advanced lipid‐lowering treatments were prescribed for 18%; 40% were on no lipid‐lowering treatment; atherosclerotic cardiovascular disease was reported in 20%; familial hypercholesterolemia diagnosis was uncommon. Conclusions Only patients with the most severe HoFH phenotypes are diagnosed early. HoFH remains challenging to treat. Results from the Family Heart Database indicate HoFH is systemically underdiagnosed and undertreated. Earlier screening, aggressive lipid‐lowering treatments, and guideline implementation are required to reduce disease burden in HoFH

New algorithms for treating homozygous familial hypercholesterolemia

Purpose of reviewWe reviewed current and future therapeutic options for patients with homozygous familial hypercholesterolemia (HoFH) and place this evidence in context of an adaptable treatment algorithm.Recent findingsLowering LDL-C levels to normal in patients with HoFH is challenging, but a combination of multiple lipid-lowering therapies (LLT) is key. Patients with (near) absence of LDL receptor expression are most severely affected and frequently require regular lipoprotein apheresis on top of combined pharmacologic LLT. Therapies acting independently of the LDL receptor pathway, such as lomitapide and evinacumab, are considered game changers for many patients with HoFH, and may reduce the need for lipoprotein apheresis in future. Liver transplantation is to be considered a treatment option of last resort. Headway is being made in gene therapy strategies, either aiming to permanently replace or knock out key lipid-related genes, with first translational steps into humans being made. Cardiovascular disease risk management beyond LDL-C, such as residual Lp(a) or inflammatory risk, should be evaluated and addressed accordingly in HoFH.SummaryHypercholesterolemia is notoriously difficult to control in most patients with HoFH, but multi-LLT, including newer drugs, allows reduction of LDL-C to levels unimaginable until a few years ago. Cost and availability of these new therapies are important future challenges to be addressed