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.
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•Early intervention is vital to prevent cardiovascular disease in homozygous familial hypercholesterolaemia (HoFH).•This consensus statement provides guidance on performing lipoprotein apheresis in children with HoFH.•Using the Delphi method involving 40 international experts, 22 statements were developed.•Statements cover indication, methods, treatment goals and follow-up of lipoprotein apheresis in children with HoFH.•Furthermore, the role of lipoprotein(a) and liver transplantation in children with HoFH is discussed.
This Review discusses new developments in understanding the basis of chylomicronaemia--a challenging metabolic disorder for which there is an unmet clinical need. Chylomicronaemia presents in two ...distinct primary forms. The first form is very rare monogenic early-onset chylomicronaemia, which presents in childhood or adolescence and is often caused by homozygous mutations in the gene encoding lipoprotein lipase (LPL), its cofactors apolipoprotein C-II or apolipoprotein A-V, the LPL chaperone lipase maturation factor 1 or glycosylphosphatidylinositol-anchored high density lipoprotein-binding protein 1. The second form, polygenic late-onset chylomicronaemia, which is caused by an accumulation of several genetic variants, can be exacerbated by secondary factors, such as poor diet, obesity, alcohol intake and uncontrolled type 1 or type 2 diabetes mellitus, and is more common than early-onset chylomicronaemia. Both forms of chylomicronaemia are associated with an increased risk of life-threatening pancreatitis; the polygenic form might also be associated with an increased risk of cardiovascular disease. Treatment of chylomicronaemia focuses on restriction of dietary fat and control of secondary factors, as available pharmacological therapies are only minimally effective. Emerging therapies that might prove more effective than existing agents include LPL gene therapy, inhibition of microsomal triglyceride transfer protein and diacylglycerol O-acyltransferase 1, and interference with the production and secretion of apoC-III and angiopoietin-like protein 3.
Familial hypercholesterolemia (FH) predisposes patients to premature cardiovascular disease, with the process of atherosclerosis initiated in early childhood.
As part of an ongoing trial to assess ...the efficacy and safety of rosuvastatin in children with FH aged 6 to 17 years, we report the differences in carotid intima-media thickness (cIMT) at baseline between children with FH and their unaffected siblings.
B-mode ultrasound measurements of the carotid artery were made in 196 children with FH and 64 of their siblings. Mean (±SE) cIMT in children with FH was significantly greater than that of unaffected siblings (0.398±0.052 versus 0.377±0.045 mm; P<0.001). A significantly greater cIMT value was observed before the age of 8 years. Multivariable analyses showed that age, male sex, and presence of FH were independent predictors of cIMT.
The difference in mean cIMT between children with FH and their unaffected siblings may be significant as early as age 8 years. This study confirms the need for early cholesterol lowering in this high-risk population. These patients participating in a carefully monitored study will help assess the long-term efficacy on cIMT and safety of statin therapy in young children.
Patients with homozygous familial hypercholesterolemia (HoFH) remain at very high cardiovascular risk despite the best standard of care lipid-lowering treatment. The addition of evinacumab, an ...angiopoietin-like protein 3 monoclonal antibody, more than halves low-density lipoprotein cholesterol in short-term studies. This study evaluated whether the evinacumab response was durable in the long term and improved cardiovascular outcome.
The OLE ELIPSE HoFH (Open-Label Extension to Evinacumab Lipid Studies in Patients With HoFH) study included newly diagnosed patients and those completing the ELIPSE HoFH trial, on stable lipid-lowering therapy including lipoprotein apheresis but not lomitapide. All patients received evinacumab (15 mg/kg intravenously) every 4 weeks, with no change in concomitant lipid-lowering treatment during the first 6 months. The primary efficacy end points were the mean absolute and percentage changes in low-density lipoprotein cholesterol from baseline to 6 months. A key secondary end point was cardiovascular event-free survival, which was compared with a control HoFH cohort not treated with evinacumab or lomitapide and matched for age, sex, and lipoprotein apheresis, derived from French Registry of Familial hypercholesterolemia.
Twelve patients, 5 women and 7 men (12-57 years), were enrolled in 3 centers in France. At 6 months, the mean low-density lipoprotein cholesterol reduction with evinacumab was 3.7 mmol/L or 56% (from 6.5 mmol/L at baseline to 2.8 mmol/L;
<0.0001) and was sustained over the median 3.5-year follow-up. No patients on evinacumab experienced cardiovascular events versus 13 events for 5/21 (24%) over 4 years in the control cohort (likelihood
=0.0267).
Real-life, long-term evinacumab adjunctive to lipid-lowering therapy including lipoprotein apheresis led to sustained low-density lipoprotein cholesterol lowering and improved cardiovascular event-free survival of patients with HoFH.
OBJECTIVE—Lp(a) is an independent, causal, genetic risk factor for cardiovascular disease and aortic stenosis. Current pharmacological lipid-lowering therapies do not optimally lower Lp(a), ...particularly in patients with familial hypercholesterolemia (FH).
APPROACH AND RESULTS—In 4 phase III trials, 382 patients on maximally tolerated lipid-lowering therapy were randomized 2:1 to weekly subcutaneous mipomersen 200 mg (n=256) or placebo (n=126) for 26 weeks. Populations included homozygous FH, heterozygous FH with concomitant coronary artery disease (CAD), severe hypercholesterolemia, and hypercholesterolemia at high risk for CAD. Lp(a) was measured 8× between baseline and week 28 inclusive. Of the 382 patients, 57% and 44% had baseline Lp(a) levels >30 and >50 mg/dL, respectively. In the pooled analysis, the mean percent decrease (median, interquartile range in Lp(a) at 28 weeks was significantly greater in the mipomersen group compared with placebo (−26.4 −42.8, −5.4 versus −0.0 −10.7, 15.3; P<0.001). In the mipomersen group in patients with Lp(a) levels >30 or >50 mg/dL, attainment of Lp(a) values ≤30 or ≤50 mg/dL was most frequent in homozygous FH and severe hypercholesterolemia patients. In the combined groups, modest correlations were present between percent change in apolipoprotein B-100 and Lp(a) (r=0.43; P<0.001) and low-density lipoprotein cholesterol and Lp(a) (r=0.36; P<0.001) plasma levels.
CONCLUSIONS—Mipomersen consistently and effectively reduced Lp(a) levels in patients with a variety of lipid abnormalities and cardiovascular risk. Modest correlations were present between apolipoprotein B-100 and Lp(a) lowering but the mechanistic relevance mediating Lp(a) reduction is currently unknown.
To identify childhood and parental factors associated with initiation of statin therapy in children with heterozygous familial hypercholesterolemia (HeFH), including underlying genetic diagnosis or ...parental premature atherosclerotic cardiovascular disease (ASCVD).
This multicenter cohort study included 245 HeFH child–parent pairs from the REFERCHOL national register (2014-2020). Demographic and clinical characteristics at the last visit were collected. Vascular disease in parents was defined as a history of ASCVD, and/or a coronary artery calcium score >100, and/or stenosis of >50% in at least carotid artery. Statistical analyses included descriptive analysis, logistic regression for univariate and multivariate effects of statins, and a sensitivity analysis combining the characteristics of children and parents.
Among the 245 children in the study cohort, 135 (58%), with a mean age of 14 ± 3 years, were treated with a statin. In multivariable analysis, the predictive childhood factors associated with statin treatment were genetic diagnosis (OR, 2.5; 95% CI, 1.3 to 4.9; P = .01), older age (OR, 4.4; 95% CI, 1.8-10.6; P = .01), more than 2 visits (OR, 2.36; 95% CI, 1.18-4.73; P = .015), and longer duration of follow-up (OR, 1.3; 95% CI, 1.1-1.6; P < .001). The predictive parental factor associated with childhood treatment was the presence of vascular disease (OR, 2.4; 95% CI, 1.0-5.7; P = .04).
HeFH confirmed by DNA testing during childhood and a history of vascular disease in parents were independently associated with statin treatment in children with HeFH. Genetic diagnosis may be useful for cardiovascular prevention in children.
Summary Background Homozygous familial hypercholesterolaemia is a rare genetic disorder in which both LDL-receptor alleles are defective, resulting in very high concentrations of LDL cholesterol in ...plasma and premature coronary artery disease. This study investigated whether an antisense inhibitor of apolipoprotein B synthesis, mipomersen, is effective and safe as an adjunctive agent to lower LDL cholesterol concentrations in patients with this disease. Methods This randomised, double-blind, placebo-controlled, phase 3 study was undertaken in nine lipid clinics in seven countries. Patients aged 12 years and older with clinical diagnosis or genetic confirmation of homozygous familial hypercholesterolaemia, who were already receiving the maximum tolerated dose of a lipid-lowering drug, were randomly assigned to mipomersen 200 mg subcutaneously every week or placebo for 26 weeks. Randomisation was computer generated and stratified by weight (<50 kg vs ≥50 kg) in a centralised blocked randomisation, implemented with a computerised interactive voice response system. All clinical, medical, and pharmacy personnel, and patients were masked to treatment allocation. The primary endpoint was percentage change in LDL cholesterol concentration from baseline. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov , number NCT00607373. Findings 34 patients were assigned to mipomersen and 17 to placebo; data for all patients were analysed. 45 patients completed the 26-week treatment period (28 mipomersen, 17 placebo). Mean concentrations of LDL cholesterol at baseline were 11·4 mmol/L (SD 3·6) in the mipomersen group and 10·4 mmol/L (3·7) in the placebo group. The mean percentage change in LDL cholesterol concentration was significantly greater with mipomersen (−24·7%, 95% CI −31·6 to −17·7) than with placebo (−3·3%, −12·1 to 5·5; p=0·0003). The most common adverse events were injection-site reactions (26 76% patients in mipomersen group vs four 24% in placebo group). Four (12%) patients in the mipomersen group but none in the placebo group had increases in concentrations of alanine aminotransferase of three times or more the upper limit of normal. Interpretation Inhibition of apolipoprotein B synthesis by mipomersen represents a novel, effective therapy to reduce LDL cholesterol concentrations in patients with homozygous familial hypercholesterolaemia who are already receiving lipid-lowering drugs, including high-dose statins. Funding ISIS Pharmaceuticals and Genzyme Corporation.
Summary Background Patients with homozygous familial hypercholesterolaemia respond inadequately to existing drugs. We aimed to assess the efficacy and safety of the microsomal triglyceride transfer ...protein inhibitor lomitapide in adults with this disease. Methods We did a single-arm, open-label, phase 3 study of lomitapide for treatment of patients with homozygous familial hypercholesterolemia. Current lipid lowering therapy was maintained from 6 weeks before baseline through to at least week 26. Lomitapide dose was escalated on the basis of safety and tolerability from 5 mg to a maximum of 60 mg a day. The primary endpoint was mean percent change in levels of LDL cholesterol from baseline to week 26, after which patients remained on lomitapide through to week 78 for safety assessment. Percent change from baseline to week 26 was assessed with a mixed linear model. Findings 29 men and women with homozygous familial hypercholesterolaemia, aged 18 years or older, were recruited from 11 centres in four countries (USA, Canada, South Africa, and Italy). 23 of 29 enrolled patients completed both the efficacy phase (26 weeks) and the full study (78 weeks). The median dose of lomitapide was 40 mg a day. LDL cholesterol was reduced by 50% (95% CI −62 to −39) from baseline (mean 8·7 mmol/L SD 2·9) to week 26 (4·3 mmol/L 2·5; p<0·0001). Levels of LDL cholesterol were lower than 2·6 mmol/L in eight patients at 26 weeks. Concentrations of LDL cholesterol remained reduced by 44% (95% CI −57 to −31; p<0·0001) at week 56 and 38% (–52 to −24; p<0·0001) at week 78. Gastrointestinal symptoms were the most common adverse event. Four patients had aminotransaminase levels of more than five times the upper limit of normal, which resolved after dose reduction or temporary interruption of lomitapide. No patient permanently discontinued treatment because of liver abnormalities. Interpretation Our study suggests that treatment with lomitapide could be a valuable drug in the management of homozygous familial hypercholesterolaemia. Funding FDA Office of the Orphan Product Development, Aegerion Pharmaceuticals.
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