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Background: Familial hypercholesterolemia (FH) is a common genetic disorder and, if not diagnosed and treated early, results in premature cardiovascular disease. Most individuals with FH are undiagnosed and machine learning offers a new prospect to improve FH identification. Our objective was to create a machine learning model from basic lipid profile data with better screening performance than LDL-C (low-density lipoprotein cholesterol) cutoff levels and diagnostic performance comparable to the Dutch Lipid Clinic Network criteria. Methods: The model was developed combining logistic regression, deep learning, and random forest classification and trained on a 70% split of a data set of individuals clinically suspected of having FH. Model performance, as well as that of the LDL-C cutoff and Dutch Lipid Clinic Network criteria, were assessed on the internal 30% testing data set and an external data set by comparing the area under the receiver operator characteristic (AUROC) curves. All methodologies were measured against the gold standard of FH diagnosis by mutation identification. Furthermore, the model was also tested on 2 lower prevalence data sets. Results: The machine learning model achieved an AUROC curve of 0.711 on the external data set (n=1376; FH prevalence=64%), which was superior to the LDL-C cutoff (AUROC=0.642) and comparable to the Dutch Lipid Clinic Network criteria (AUROC=0.705). The model performed even better when tested on the medium-prevalence (n=2655; FH prevalence=20%) and low-prevalence (n=1616; FH prevalence=1%) data sets, with AUROC curve values of 0.801 and 0.856, respectively. Conclusions: Despite absence of clinical information, the model better identified genetically confirmed FH in a cohort of individuals suspected of having FH than LDL-C cutoff values and was comparable to the Dutch Lipid Clinic Network criteria. The model achieved higher accuracy when tested on 2 cohorts with lower FH prevalence. The application of machine learning is, therefore, a promising tool in both the screening for, and diagnosis of, individuals with FH.

Background: Homozygous familial hypercholesterolemia (HoFH) is characterized by markedly elevated levels of low-density lipoprotein cholesterol (LDL-C) and premature cardiovascular disease. This analysis evaluated LDL-C changes in patients with HoFH who sequentially participated in interventional trials with alirocumab (NCT03156621) and evinacumab (NCT03399786). Methods: A total of 25 patients completed the alirocumab trial and entered the evinacumab trial and were randomized to intravenous evinacumab 15 mg/kg (n=16) or placebo (n=9) every 4 weeks. The primary outcome for the evinacumab trial was percent change in LDL-C from baseline to week 24. Results: Baseline characteristics were generally well balanced. Among patients who participated in the alirocumab trial, a reduction in LDL-C of –44.6% and –1.1% was observed at week 24 in patients treated with evinacumab versus placebo, respectively. Overall, mean total reductions in LDL-C (Figure) and apolipoprotein B of -62.9% and -54.9%, respectively, were observed in patients treated with the combination of alirocumab and evinacumab; and triglycerides were lowered by -54.5%. The absolute LDL-C reduction from their baseline in patients treated with the combination of alirocumab and evinacumab was -216.3 mg/dL. No new safety signals were observed when treated with alirocumab and evinacumab, and were consistent with the respective trial results. Conclusions: Combination therapy with alirocumab and evinacumab reduced LDL-C by more than 60% in patients with HoFH and was well tolerated.

Homozygous familial hypercholesterolemia is a genetic disorder characterized by low-density lipoprotein (LDL)-receptor dysfunction, markedly elevated levels of LDL-cholesterol (LDL-C) and premature atherosclerosis. Patients are often poorly responsive to conventional lipid-lowering therapies that upregulate LDL-receptor expression.1 Lomitapide inhibits microsomal triglyceride transfer protein, which lipidates nascent apolipoprotein (apo)B-containing lipoproteins. In a pivotal 78-week open-label trial, lomitapide, titrated to the maximal tolerable dose, decreased LDL-C by 50% at the end of the efficacy phase (week 26) in patients with homozygous familial hypercholesterolemia.2 The principal adverse events included gastrointestinal disturbances, hepatic enzyme elevations, and increased liver fat. Here we provide additional long-term efficacy and safety data, including an exploratory analysis of the potential metabolic consequences of hepatic fat accumulation from an extension trial (NCT00943306). Patients continued on lomitapide at the maximally tolerated dose until transition to commercial or compassionate lomitapide. Lipid-lowering therapies, including apheresis, could be modified at the investigator’s discretion if LDL-C was

Objective— Proprotein convertase subtilisin kexin type 9 (PCSK9) inhibitors lower low-density lipoprotein (LDL) cholesterol in the vast majority of patients with autosomal dominant familial hypercholesterolemia. Will PCSK9 inhibition with monoclonal antibodies, in particular alirocumab, be of therapeutic value for patients with autosomal recessive hypercholesterolemia (ARH)? Approach and Results— Primary lymphocytes were obtained from 28 genetically characterized ARH patients and 11 controls. ARH lymphocytes treated with mevastatin were incubated with increasing doses of recombinant PCSK9 with or without saturating concentrations of alirocumab. Cell surface LDL receptor expression measured by flow cytometry and confocal microscopy was higher in ARH than in control lymphocytes. PCSK9 significantly reduced LDL receptor expression in ARH lymphocytes albeit to a lower extent than in control lymphocytes (25% versus 76%, respectively), an effect reversed by alirocumab. Fluorescent LDL cellular uptake, also measured by flow cytometry, was reduced in ARH lymphocytes compared with control lymphocytes. PCSK9 significantly lowered LDL cellular uptake in ARH lymphocytes, on average by 18%, compared with a 46% reduction observed in control lymphocytes, an effect also reversed by alirocumab. Overall, the effects of recombinant PCSK9, and hence of alirocumab, on LDL receptor expression and function were significantly less pronounced in ARH than in control cells. Conclusions— PCSK9 inhibition with alirocumab on top of statin treatment has the potential to lower LDL cholesterol in some autosomal recessive hypercholesterolemia patients.

Rationale : Vitamin E transport and steroidogenesis are closely associated with low-density lipoproteins (LDLs) metabolism, and evolocumab can lower LDL cholesterol (LDL-C) to low levels. Objective: To determine the effects of evolocumab on vitamin E and steroid hormone levels. Methods and Results: After titration of background lipid-lowering therapy per cardiovascular risk, 901 patients with an LDL-C ≥2.0 mmol/L were randomized to 52 weeks of monthly, subcutaneous evolocumab, or placebo. Vitamin E, cortisol, adrenocorticotropic hormone, and gonadal hormones were analyzed at baseline and week 52. In a substudy (n=100), vitamin E levels were also measured in serum, LDL, high-density lipoprotein, and red blood cell membranes at baseline and week 52. Absolute vitamin E decreased in evolocumab-treated patients from baseline to week 52 by 16% but increased by 19% when normalized for cholesterol. In the substudy, vitamin E level changes from baseline to week 52 mirrored the changes in the lipid fraction, and red blood cell membrane vitamin E levels did not change. Cortisol in evolocumab-treated patients increased slightly from baseline to week 52, but adrenocorticotropic hormone and the cortisol:adrenocorticotropic hormone ratio did not change. No patient had a cortisol:adrenocorticotropic hormone ratio Conclusions: As expected, vitamin E levels changed similarly to lipids among patients treated for 52 weeks with evolocumab. No adverse effects were observed in steroid or gonadal hormones, even at very low LDL-C levels. Clinical Trial Registration: URL: http://www.clinicaltrials.gov . Unique identifier: NCT01516879.

To review publications in the English literature over the past 18 months relating to the management of homozygous familial hypercholesterolaemia.Experience with plasmapheresis has been summarized, guidelines are being introduced to enhance patient care and registries are under consideration to improve analysis of management in this rare but serious disorder. Liver transplantation has been reviewed for its biochemical efficacy, but still does not ensure freedom from vascular complications. For patients without access to plasmapheresis, there is now evidence that high-dose statins do improve the prognosis, but combination therapy with additional agents should still be considered for better outcome. Promising new agents that inhibit LDL production by limiting apolipoprotein B100 synthesis by means of antisense oligonucleotides (mipomersen) or by inhibition of microsomal triacylglycerol transfer protein (lomitapide) have made significant additional LDL reduction possible but are associated with hepatic fat accumulation and long-term safety data is still required. Several other lipid modulating agents and gene therapy are still being explored.The management of homozygous familial hypercholesterolaemia by pharmacological means is improving with agents that limit lipoprotein production but plasmapheresis, generally in combination with additional pharmacological treatment, remains the proven option. Liver transplantation is now less likely to be undertaken owing to improved pharmacological options and prognosis.

Background: Homozygous familial hypercholesterolemia (HoFH) is a rare genetic condition characterized by highly elevated low-density lipoprotein cholesterol (LDL-C) levels and high cardiovascular disease risk. Lomitapide, an oral microsomal triglyceride transfer protein inhibitor, was approved for the treatment of adult HoFH based on a small phase 3 study. We report efficacy and safety results from the phase 3 long-term extension study. Methods: Eligible HoFH patients completing the 78-wk phase 3 pivotal trial were enrolled into a single-arm extension study where lomitapide was administered daily at the maximum tolerated dose (5-60mg/d) until lomitapide was commercially available in the patient’s country. Concurrent lipid-lowering therapies, including apheresis, were permitted. Results: Nineteen of 23 patients who completed the pivotal study entered the extension trial (9/19 apheresis) with 16 patients completing all end of study assessments. Mean treatment duration was 4.8 yrs (range 2.1-5.7 yrs, median 5.1 yrs). Lomitapide efficacy was maintained throughout the study (Table). Reported adverse events were similar to those in the pivotal phase 3 study (chiefly gastrointestinal). Five patients (26%) experienced transient alanine aminotransferase (ALT) elevations ≥5x upper limit of normal (ULN) that were successfully managed by dose adjustment in all but one patient who was discontinued due to persistent excessive alcohol use. One 58 year-old patient with known CAD had sudden cardiac death. Median hepatic fat increased by 10% above baseline after 3 yrs and stabilized through the treatment period (Table). No other clinically relevant findings were identified to date. Conclusions: The long-term efficacy of lomitapide was maintained up to 5.7 yrs in patients completing the phase 3 trial with no new safety signals observed. The clinical significance of the increase in hepatic fat remains unknown.

Background— Homozygous familial hypercholesterolemia is an inherited disorder caused by mutations in both low-density lipoprotein receptor alleles, which results in extremely elevated plasma low-density lipoprotein cholesterol concentrations and very early morbidity and mortality due to cardiovascular disease. Methods and Results— To evaluate the impact of advances in lipid-lowering (predominantly statin) therapy on cardiovascular disease morbidity and mortality in a large cohort of patients with homozygous familial hypercholesterolemia, the records of 149 patients (81 females, 68 males) from 2 specialized lipid clinics in South Africa were evaluated retrospectively. Homozygous familial hypercholesterolemia was diagnosed by confirmation of mutations in genes affecting low-density lipoprotein cholesterol or by clinical criteria. A Cox proportional hazard model with time-varying exposure was used to estimate the risk of death and major adverse cardiovascular events among statin-treated patients compared with statin-naive patients. The hazard ratio for benefit from lipid therapy, calculated with the Cox proportional hazards model for the end point of death, was 0.34 (95% confidence interval 0.14–0.86; P =0.02), and for the end point of major adverse cardiovascular events, it was 0.49 (95% confidence interval 0.22–1.07; P =0.07). This occurred despite a mean reduction in low-density lipoprotein cholesterol of only 26.4% (from 15.9±3.9 to 11.7±3.4 mmol/L; P Conclusions— Lipid-lowering therapy is associated with delayed cardiovascular events and prolonged survival in patients with homozygous familial hypercholesterolemia.