Homozygous Familial Hypercholesterolemia Patients Research Articles

Efficacy of Inclisiran in Patients Having Familial Hypercholesterolemia: Heterozygous Compared to Homozygous Trait, a Systematic Review and Meta-analysis.

To find out whether inclisiran sodium has different efficacy in heterozygous familial hypercholesterolemia (HeFH) and homozygous familial hypercholesterolemia (HoFH) patient groups. We conducted the systematic review and meta-analysis of ORION clinical trials. PubMed, Embase, and Clinicaltrials.gov databases were searched for the relevant studies. Atheroscalerotic parameters considered for our objective were low-density lipoprotein cholesterol, total cholesterol, proprotein convertase subtilisin/kexin type 9 (PCSK9), apolipoprotein B, and nonhigh-density lipoprotein cholesterol. Primary outcomes were the percentage difference in atheroscalerotic parameters at follow-up relative to baseline values. Our study examined these primary outcomes to determine whether there is a statistically significant difference between the HeFH and HoFH groups. Risk of bias was assessed by the Cochrane risk of bias tool. Meta-analysis was performed when at least 2 studies reported on the same variable. Four ORION clinical trials provided the data related to the mean difference in the atheroscalerotic parameters at follow-up relative to baseline, of HeFH and HoFH patient populations, after administration of 300 mg inclisiran subcutaneously. We pooled together these mean differences for each group and applied a statistical test to analyze if the values were significantly different between the groups. The results of our study unveiled the significant difference in pooled mean differences in low-density lipoprotein cholesterol (HeFH: -48.62%; HoFH: -9.12%; P < 0.05), total cholesterol (HeFH: -30.31%; HoFH: -11.50%; P < 0.05), apolipoprotein (HeFH: -39.97%; HoFH: -14.68%; P < 0.05), and nonhigh-density lipoprotein (HeFH: -44.51%; HoFH: -12.22%; P < 0.05) between HeFH and HoFH groups. However, the difference in pooled mean difference in PCSK9 values (HeFH: -68.41%; HoFH: -56.25%; P = 0.2) between HeFH and HoFH groups was statistically insignificant. Studies were of high quality. There was a significant difference in the reductions in atherosclerotic lipid parameters in heterozygous and homozygous populations after the administration of inclisiran except for PCSK9 parameter. Further studies are needed to support this conclusion.

A machine-learning algorithm using claims data to identify patients with homozygous familial hypercholesterolemia

Homozygous familial hypercholesterolemia (HoFH) is an underdiagnosed and undertreated ultra-rare disease. We utilized claims data from the Komodo Healthcare Map database to develop a machine-learning model to identify potential HoFH patients. We tokenized patients enrolled in MyRARE (patient support program for those prescribed evinacumab-dgnb in the United States) and linked them with their Komodo claims. A true positive HoFH cohort (n = 331) was formed by including patients from MyRARE and patients with prescriptions for evinacumab-dgnb or lomitapide. The negative cohort (n = 1423) comprised patients with or at risk for cardiovascular disease. We divided the cohort into an 80% training and 20% testing set. Overall, 10,616 candidate features were investigated; 87 were selected due to clinical relevance and importance on prediction performance. Different machine-learning algorithms were explored, with fast interpretable greedy-tree sums selected as the final machine-learning tool. This selection was based on its satisfactory performance and its easily interpretable nature. The model identified four useful features and yielded precision (positive predicted value) of 0.98, recall (sensitivity) of 0.88, area under the receiver operating characteristic curve of 0.98, and accuracy of 0.97. The model performed well in identifying HoFH patients in the testing set, providing a useful tool to facilitate HoFH screening and diagnosis via healthcare claims data.

Identification of a novel LDLR p.Glu179Met variant in Thai families with familial hypercholesterolemia and response to treatment with PCSK9 inhibitor

Familial hypercholesterolemia (FH) is a genetic disease characterized by elevated LDL-C levels. In this study, two FH probands and 9 family members from two families from northeastern Thailand were tested for LDLR, APOB, and PCSK9 variants by whole-exome sequencing, PCR-HRM, and Sanger sequencing. In silico analysis of LDLR was performed to analyse its structure‒function relationship. A novel variant of LDLR (c.535_536delinsAT, p.Glu179Met) was detected in proband 1 and proband 2 in homozygous and heterozygous forms, respectively. A total of 6 of 9 family members were heterozygous for LDLR p.Glu179Met variant. Compared with proband 2, proband 1 had higher baseline TC and LDL-C levels and a poorer response to lipid-lowering therapy combined with a PCSK9 inhibitor. Multiple sequence alignment showed that LDLR p.Glu179Met was located in a fully conserved region. Homology modelling demonstrated that LDLR p.Glu179Met variant lost one H-bond and a negative charge. In conclusion, a novel LDLR p.Glu179Met variant was identified for the first time in Thai FH patients. This was also the first report of homozygous FH patient in Thailand. Our findings may expand the knowledge of FH-causing variants in Thai population, which is beneficial for cascade screening, genetic counselling, and FH management to prevent coronary artery disease.

Improved lipid-lowering treatment and reduction in cardiovascular disease burden in homozygous familial hypercholesterolemia: The SAFEHEART follow-up study

AimWe aimed to describe clinical and genetic characteristics, lipid-lowering treatment and atherosclerotic cardiovascular disease (ASCVD) outcomes over a long-term follow-up in homozygous familial hypercholesterolemia (HoFH). MethodsSAFEHEART (Spanish Familial Hypercholesterolaemia Cohort Study) is a long-term study in molecularly diagnosed FH. Data analyzed in HoFH were prospectively obtained from 2004 until 2022. ASCVD events, lipid profile and lipid-lowering treatment were determined. ResultsThirty-nine HoFH patients were analyzed. The mean age was 42 ± 20 years and nineteen (49%) were women. Median follow-up was 11 years (IQR 6,18). Median age at genetic diagnosis was 24 years (IQR 8,42). At enrolment, 33% had ASCVD and 18% had aortic valve disease. Patients with new ASCVD events and aortic valve disease at follow-up were six (15%), and one (3%), respectively. Median untreated LDL-C levels were 555 mg/dL (IQ 413,800), and median LDL-C levels at last follow-up was 122 mg/dL (IQR 91,172). Most patients (92%) were on high intensity statins and ezetimibe, 28% with PCSK9i, 26% with lomitapide, and 23% with lipoprotein-apheresis. Fourteen patients (36%) attained an LDL-C level below 100 mg/dL, and 10% attained an LDL-C below 70 mg/dL in secondary prevention. Patients with null/null variants were youngers, had higher untreated LDL-C and had the first ASCVD event earlier. Free-event survival is longer in patients with defective variant compared with those patients with at least one null variant (p=0.02). ConclusionsHoFH is a severe life threating disease with a high genetic and phenotypic variability. The improvement in lipid-lowering treatment and LDL-C levels have contributed to reduce ASCVD events.

Contemporary lipid-lowering management and risk of cardiovascular events in homozygous familial hypercholesterolaemia: insights from the Italian LIPIGEN Registry.

The availability of novel lipid-lowering therapies (LLTs) has remarkably changed the clinical management of homozygous familial hypercholesterolaemia (HoFH). The impact of these advances was evaluated in a cohort of 139 HoFH patients followed in a real-world clinical setting. The clinical characteristics of 139 HoFH patients, along with information about LLTs and low-density lipoprotein cholesterol (LDL-C) levels at baseline and after a median follow-up of 5 years, were retrospectively retrieved from the records of patients enrolled in the LIPid transport disorders Italian GEnetic Network-Familial Hypercholesterolaemia (LIPIGEN-FH) Registry. The annual rates of major atherosclerotic cardiovascular events (MACE-plus) during follow-up were compared before and after baseline. Additionally, the lifelong survival free from MACE-plus was compared with that of the historical LIPIGEN HoFH cohort. At baseline, LDL-C level was 332 ± 138 mg/dL. During follow-up, the potency of LLTs was enhanced and, at the last visit, 15.8% of patients were taking quadruple therapy. Consistently, LDL-C decreased to an average value of 124 mg/dL corresponding to a 58.3% reduction (Pt < 0.001), with the lowest value (∼90 mg/dL) reached in patients receiving proprotein convertase subtilisin/kexin type 9 inhibitors and lomitapide and/or evinacumab as add-on therapies. The average annual MACE-plus rate in the 5-year follow-up was significantly lower than that observed during the 5 years before baseline visit (21.7 vs. 56.5 per 1000 patients/year; P = 0.0016). Our findings indicate that the combination of novel and conventional LLTs significantly improved LDL-C control with a signal of better cardiovascular prognosis in HoFH patients. Overall, these results advocate the use of intensive, multidrug LLTs to effectively manage HoFH.

Lomitapide for the treatment of paediatric homozygous familial hypercholesterolaemia patients - Results from the efficacy phase of the APH-19 study

Lomitapide for the treatment of paediatric homozygous familial hypercholesterolaemia patients - Results from the efficacy phase of the APH-19 study

Abstract 15073: Response to PCSK9 Inhibition in Homozygous Familial Hypercholesterolemia Patients is Variable in Different Regions of the World and According to Age

Background: Reductions in LDL-C with PCSK9-inhibition in HoFH subjects are highly variable even within populations with the same pathogenic variants. Whilst initial studies were done in HoFH patients of European decent, recent studies from India and other countries with novel pathogenic variants as well as studies in paediatric patients have shown substantially less response to PCSK9 inhibition. In the global phase 3 LIBerate-HoFH trial, we evaluated two different PCSK9 inhibitors, lerodacibep (LIB) 300 mg SC QM and evolocumab (EVO) 420 mg SC QM in genetically confirmed HoFH patients on stable background lipid lowering therapy. Methods: Eligible patients (age ≥10 years) were randomized to either LIB or EVO for 24 weeks (Period A) followed by an 8 week ‘washout’ and crossed over to the alternate drug for the next 24 weeks (Period B). In a post-hoc analysis, the mean reduction in average LDL-C with both drugs were evaluated according to various world regions and age. Results: Of 65 who entered Period A, 56 completed both periods: 31 in USA/Europe/Israel/South Africa; 15 in India and 10 in Turkey. Mean baseline LDL-C was 401 mg/dL; 55% were female and 19(34%) were adolescents aged &lt;18 years. For the total population, the mean (SE) reduction in average LDL-C was -9.6% (3.25) on LIB and -11.7% (3.65) on EVO (p=0.44, NS). LDL-C reductions varied considerably in different regions and response was poorer in the adolescent subjects. However, reductions in LDL-C of ≥15% were seen in 26.8% (n=15) with LIB and 37.5% (n=21) with EVO - Table. Conclusions: Reductions in LDL-C achieved with PCSK9-inhibition in HoFH subjects are highly variable and differ according to region and age. However, given the clinically significant reductions in LDL-C in 1/3 of patients including patients from India and Turkey with null/null or novel variants, PCSK9 inhibition should remain part of standard of care for HoFH patients who remain with elevated LDL-C levels despite treatment with statin and ezetimibe.

Abstract 16672: Effects of Evinacumab on Atherogenic Lipoproteins in Children and Adolescents From Ages 5 to 17 Years With Homozygous Familial Hypercholesterolemia

Background: Homozygous familial hypercholesterolemia (HoFH) is characterized by severely elevated LDL-C levels from birth. Diagnosis and aggressive LDL-lowering treatment (LLT) before adulthood are essential for optimal ASCVD prevention in HoFH; however, it is often undiagnosed and undertreated in pediatric patients. Specifically, HoFH children and adolescents routinely require advanced LLT, since few achieve LDL-C goal on standard LLT. Evinacumab, a novel angiopoietin-like-3 inhibitor and advanced LLT, has an established safety profile in younger and older pediatric HoFH patients, 5-11 and 12-17 years, respectively. For the first time, we compare its lipid efficacy in these two groups. Methods: Fourteen patients ages 5-11 years (Study 17100 part B; NCT04233918) and 14 patients ages 12-17 years (Study 1719; NCT03409744), all with HoFH on stable LLT, were treated with IV evinacumab 15 mg/kg Q4W. Notably, in Study 17100 part B, no patients were taking PCSK9 inhibitors at study entry, while in Study 1719, 42.9% of patients were receiving a PCSK9 inhibitor at baseline. Apheresis use differed little, 50.0% in the younger study vs 64.3% in the older. LDL-C and other atherogenic lipoproteins were tested at baseline and 24 weeks. Results: In patients ages 5-11 years, mean (SD) baseline LDL-C was 263.7 (91.0) mg/dL and was lowered 48.3% (131.9 mg/dL) by evinacumab ( Table ). In patients ages 12-17 years, baseline LDL-C was 300.4 (100.5) mg/dL and was lowered 55.4% (180.5 mg/dL), with similar baseline and changes to those of the younger patients. In both groups, evinacumab markedly reduced ApoB, non-HDL-C, and Lp(a) ( Table ). Conclusions: Evinacumab strikingly and comparably reduces atherogenic lipids in younger and older pediatric HoFH patients. Since standard LLT rarely lowers LDL-C levels to treatment goals in pediatric HoFH, evinacumab should be strongly and urgently considered in these patients whenever further LDL-lowering is needed after optimizing standard LLT.

OR24-02 Case Series Of Canadian Patients With Homozygous Familial Hypercholesterolemia Treated With ANGPTL3 Inhibitor Evinacumab

Abstract Disclosure: I. Shamsudeen: None. B.W. McCrindle: Consulting Fee; Self; Jansen Pharmaceuticals, Amryt, Ultragenyx, Chiesi, Esperion. R.A. Hegele: Advisory Board Member; Self; Amgen Inc, HLS Pharmaceuticals, Novartis Pharmaceuticals. Consulting Fee; Self; Akcea Therapeutics, Ultragenyx, Medison, Acasti, Amgen Inc, Novartis Pharmaceuticals, Amryt, Amgen Inc, Pfizer, Inc., Arrowhead, Sanofi, HLS Pharmaceuticals, Regeneron Pharmaceuticals. Background: Homozygous familial hypercholesterolemia (HoFH) is an ultrarare, life-threatening condition characterized by markedly elevated levels of low-density lipoprotein cholesterol (LDL-C) due to biallelic LDL receptor variants. Patients have an increased risk of premature atherosclerotic cardiovascular disease (ASCVD). Traditional lipid-lowering agents are minimally effective and the gold standard treatment is serial apheresis. Recently, an angiopoietin-like protein 3 (ANGPTL3) inhibitor, evinacumab, was introduced as a promising new treatment for HoFH. It was FDA-approved in 2021, but is currently available in Canada only through clinical trials or special access programs. Case Presentations: The first five Canadian HoFH patients to receive evinacumab via special access are presented. Their mean age is 24.6 years (SD = 13.9). As of December 2022, they have received evinacumab 15 mg/kg intravenously every four weeks for a mean of 12.2 months (SD = 11.3). Their mean incremental LDL-C reduction is 49.4% (SD = 8.9) on evinacumab along with reduced apheresis frequency for those on serial apheresis. Safety labs for all patients are normal. Brief case summaries are as follows: (a) Patient A is a 36-year-old man with severe ASCVD who has been on evinacumab for 30 months, in addition to a statin, ezetimibe, evolocumab and LDL-apheresis. His time-averaged LDL-C has decreased by 46.2%, from 4.76 to 2.56 mmol/L (184 to 99 mg/dL), on evinacumab. (b) Patient B is a 17-year-old male with elevated LDL-C levels despite being on a statin, ezetimibe and LDL-apheresis. After 14 months on evinacumab, his time-averaged LDL-C reduced by 40.3%, from 8.75 to 5.22 mmol/L (338 to 202 mg/dL). (c) Patient C is a 30-year-old woman with ASCVD and xanthomas on a statin and ezetimibe, but not apheresis. She has been on evinacumab for 12 months with a 57.7% reduction in LDL-C, from 11.43 to 4.83 mmol/L (442 to 187 mg/dL). (d) Patient D is a 36-year-old man with ASCVD on a statin, ezetimibe, evolocumab and lomitapide in addition to plasmapheresis. He started evinacumab 2 months ago and has already had a 42.6% decrease in time-averaged LDL-C, from 4.34 to 2.49 mmol/L (168 to 96 mg/dL). (e) Patient E is a 4-year-old boy with HoFH and xanthomas on a statin, ezetimibe and plasmapheresis. After 3 months of treatment with evinacumab, his time-averaged LDL-C decreased by 59.9%, from 9.45 to 3.79 mmol/L (365 to 147 mg/dL). Concurrently, he has developed unexplained intermittent abdominal pain, with temporary suspension of evinacumab pending further assessment. Discussion: Five HoFH patients with distinctive histories, baseline treatments and ASCVD have all shown marked improvement in LDL-C levels with a mean reduction of 49.4% on evinacumab on top of existing therapy. Overall, observations from our case series suggest that evinacumab is an effective new treatment for HoFH, a life-threatening condition with few therapeutic options. Presentation: Saturday, June 17, 2023

Generation of a familial hypercholesterolemia model in non-human primate

Familial hypercholesterolemia (FH) is an inherited autosomal dominant disorder that is associated with a high plasma level of low-density lipoprotein (LDL) cholesterol, leading to an increased risk of cardiovascular diseases. To develop basic and translational research on FH, we here generated an FH model in a non-human primate (cynomolgus monkeys) by deleting the LDL receptor (LDLR) gene using the genome editing technique. Six LDLR knockout (KO) monkeys were produced, all of which were confirmed to have mutations in the LDLR gene by sequence analysis. The levels of plasma cholesterol and triglyceride were quite high in the monkeys, and were similar to those in FH patients with homozygous mutations in the LDLR gene. In addition, periocular xanthoma was observed only 1 year after birth. Lipoprotein profile analysis showed that the plasma very low-density lipoprotein and LDL were elevated, while the plasma high density lipoprotein was decreased in LDLR KO monkeys. The LDLR KO monkeys were also strongly resistant to medications for hypercholesterolemia. Taken together, we successfully generated a non-human primate model of hypercholesterolemia in which the phenotype is similar to that of homozygous FH patients.

Familial Hypercholesterolaemia in Children and Adolescents: Current and Future Perspectives.

Familial hypercholesterolemia (FH) is a genetic disease, the underlying cause of which is represented by mutations capable of influencing the metabolism of low-density lipoproteins (LDL). The distinguishing characteristic of FH has increased LDL cholesterol blood levels since birth, triggering early development of atherosclerosis-related diseases. Diagnosis of FH is frequently either missed or made with a considerable delay. Prompt identification of the disease is pivotal in implementing early prevention measures. Safe and effective drugs have been approved for use in children and adolescents, with statins, with or without ezetimibe, representing first-line therapy. At times, however, these medications may not be sufficient to achieve the therapeutic target, particularly in homozygous FH patients. Lipoprotein apheresis, which has proved safe and efficient, is strongly suggested in such cases. New drugs still at the investigational stage may represent a promising and personalised therapy. Lowering cholesterol levels in childhood hampers the formation of arterial atherosclerotic plaques, thus reducing cardiovascular events later in life. Accordingly, early detection, diagnosis, and therapy in FH subjects are priority aims.

Randomized, open-label, cross-over, phase-3 study to evaluate efficacy and safety of LIB003 compared with evolocumab in homozygous familial hypercholesterolaemia patients on stable lipid-lowering therapy (liberate-HOFH)

Randomized, open-label, cross-over, phase-3 study to evaluate efficacy and safety of LIB003 compared with evolocumab in homozygous familial hypercholesterolaemia patients on stable lipid-lowering therapy (liberate-HOFH)

Lomitapide for the treatment of paediatric homozygous familial hypercholesterolaemia patients - Results from the efficacy phase of the APH-19 study

Lomitapide for the treatment of paediatric homozygous familial hypercholesterolaemia patients - Results from the efficacy phase of the APH-19 study

Modelling the potential long-term survival benefit of evinacumab treatment vs. standard of care in patients with homozygous familial hypercholesterolaemia.

Despite intensive lipid-lowering therapies (LLTs), most patients with homozygous familial hypercholesterolaemia (HoFH) do not achieve guideline recommended low-density lipoprotein cholesterol (LDL-C) targets and are at increased risk of premature cardiovascular death. This analysis aimed to predict the impact of evinacumab and standard-of-care LLTs on life expectancy in an HoFH population using mathematical modelling. Mathematical models were developed using efficacy data for evinacumab from the phase 3 ELIPSE HoFH trial plus efficacy data for standard-of-care LLTs from peer-reviewed publications. Treatment strategies evaluated included (i) untreated, (ii) high-intensity statin (HIS) only, (iii) HIS plus ezetimibe, (iv) HIS plus ezetimibe plus proprotein convertase subtilisin/kexin type 9 inhibitor (PCSK9i), and (v) HIS plus ezetimibe plus PCSK9i plus evinacumab. Markov analyses were used to assess differences in survival probability for different LLT strategies. The median survival for untreated HoFH patients was only 33-43 years, depending on different assumptions on baseline untreated LDL-C levels. In the most robust model, we estimated that HIS increased median survival by 9 years and ezetimibe further increased median survival by an additional 9 years. When PCSK9i was added on top of HIS plus ezetimibe, median survival was further improved by 14 years. Finally, the addition of evinacumab to standard-of-care LLTs was estimated to increase median survival by ∼12 years. In this mathematical modelling analysis, evinacumab treatment could potentially increase long-term survival vs. standard-of-care LLTs for patients with HoFH.

Successful treatment with lomitapide in a patient with homozygous familial hypercholesterolemia and severe fatty liver disease

Introduction and Aims: Homozygous-familial hypercholesterolemia (Ho-FH) is a rare condition due to biallelic mutations in low-density lipoprotein-receptor (LDL-R) genes characterized by high level of LDL-cholesterol (LDL-c) and huge risk of premature atherosclerotic cardiovascular disease (ASCVD), determining low quality of life and life expectancy. Lomitapide represents a therapeutic option for Ho-FH, but caution should be observed when used in fatty liver disease (FLD) and hypertransaminasemia since it is associated with onset/worsening of liver steatosis. We present a case of safe lomitapide therapy in an adult Ho-FH patient with pre-existing FLD. Case presentation: A 39-year-old man with severe hypercholesterolemia since childhood (LDL-c 405 mg/dl) and premature coronary heart disease history, was referred to our Modena Lipid Clinic. He presented an overt metabolic syndrome, FLD with hypertransaminasemia and elastosonographic significant liver fibrosis. Lipid-lowering-therapy (LLT) included rosuvastatin 20 mg, ezetimibe and evolocumab 140 mg twice a month without reaching LDL-c goal. Genetic analysis revealed homozygous pathogenic LDL-R gene mutation. Evolocumab was increased up to 420 mg twice a month and LDL-apheresis was started with quality of life worsening. Therefore, lomitapide 5 mg daily and low-fat diet were started, obtaining weight loss and lipid profile improvement. However, liver enzymes elevation higher than 5-fold was observed, leading to lomitapide discontinuation and baseline liver enzymes values restoration. After one-month wash-out, lomitapide was gradually reintroduced up to 5 mg daily without significant hypertransaminasemia recurrence, leading to LDL-c target achievement and LDL-apheresis discontinuation. Adherence to low-fat diet and weight loss resulted in FLD and fibrosis improvement. Conclusion: Ho-FH requires complex, combined treatment. Metabolic comorbidities co-existence makes Ho-FH management more difficult. Lomitapide can be safely used in Ho-FH patients with FLD and hypertransaminasemia, but strict follow-up of liver disease and a multidisciplinary approach are needed. Before lomitapide introduction, low-fat diet should be started advantageously and weight stabilization should be obtained.

Genotype-phenotype correlation in a large cohort of pediatric patients with heterozygous and homozygous familial hypercholesterolemia.

Familial hypercholesterolemia (FH) is a genetic disorder characterized by elevated low-density lipoprotein cholesterol (LDL-C) levels and premature cardiovascular disease (CVD). Both the heterozygous form and the very severe homozygous form can be diagnosed by genetic testing and by clinical criteria. Genetic testing can discern FH in a form caused by complete absence of the LDL-receptors, the negative variant and a form leading to reduced activity of the LDL receptors, the defective variant. The aim of this study is to provide more insight in the genotype-phenotype correlation in children and adolescents diagnosed with heterozygous FH (HeFH) and with homozygous FH (HoFH), specifically in relation to the clinical and therapeutic consequences of the negative and defective variant of FH. Data of 5904 children with a tentative diagnosis of FH referred to our center for genetic testing were collected. A lipid-profile was present in 3494 children, who became the study cohort. In this large cohort of children, which includes 2714 HeFH and 41 HoFH patients, it is shown that receptor negative variants are associated with significant higher LDL-C levels in HeFH patients than receptor defective variants (6.0 versus 4.9 mmol/L; p < 0.001). A negative/negative variant is associated with a significant higher LDL-C level jn HoFH patients than a negative/defective variant, which in itself has a higher LDL-C level than a defective/defective variant. Significantly more premature CVD is present in close relatives of children with HeFH with negative variants compared to close relatives of HeFH children with defective variants (75% vs 59%; p < 0.001). Performing genetic testing and identifying the type of underlying genetic variant is of added value in order to distinguish between pediatric patients with higher risks of premature CVD and to identify those that will benefit most from new types of lipid-lowering therapies. Since in children the phenotype of FH is less affected by environmental factors, the study substantiates the genotype-phenotype correlation in this large pediatric population.

Gene and cell therapy approaches for familial hypercholesterolemia: An update.

Familial hypercholesterolemia (FH) is a common autosomal codominant hereditary illness marked by the heightened risk of early atherosclerotic cardiovascular disease and high blood levels of low-density lipoprotein cholesterol (LDL-C). FH patients can have homozygous or heterozygous variants. This condition has been linked to variations in the genes for the LDL receptor (LDLR), apolipoprotein B, proprotein convertase subtilisin/Kexin 9 (PCSK9), and LDLR adaptor protein 1. Drugs such as statins, ezetimibe, and PCSK9 inhibitors are currently widely available, allowing for the theoretical normalization of plasma LDL-C levels mostly in patients with heterozygous FH. However, homozygous FH patients usually have a poor response to traditional lipid-lowering therapy and may have a poor prognosis at a young age. LDL apheresis and novel pharmacological therapies such as microsomal transfer protein inhibitors or anti-angiopoietin-like protein 3 monoclonal antibodies are extremely expensive and unavailable in most regions of the world. Therefore, the unmet need persists for these patients. In this review, we discuss the numerous gene delivery, gene editing, and stem cell manipulation techniques used in this study to correct FH-causing LDLR gene variations in vitro, ex vivo, and in vivo. Finally, we looked at a variety of studies that corrected genetic defects that caused FH using the ground-breaking clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) gene editing technology.

Management and clinical outcomes of patients with homozygous familial hypercholesteremia in Saudi Arabia.

We report the incidence, patient characteristic with clinical outcomes in patients with homozygous familial hypercholesterolemia (HoFH) in Saudi Arabia. This is a retrospective and prospective, single center study which included 37 patients 14 years and older enrolled and followed up between 2018-2021 for three years. 46% were females, 78% were offspring of consanguineous marriage. LDLR mutation was in 78% and LDL-C/LDLRAP in 3% of patients. Mean LDL-C at the first presentation was 14.2±3.7 mmol/L, average Dutch lipid score was 20.9±6.24. LDL apheresis was performed on 70% of patients. Most patients were on ezetimibe (92%), high-dose statins ( 84%) and PCSK9 inhibitors (32%). 48.6% had aortic stenosis, out of which 30% had severe aortic stenosis. Ten underwent aortic valve surgery (5 mechanical valve, 3 Ross procedure, 1 aortic valve repair, 1 bioprosthetic valve) and one had transcatheter aortic valve implantation (TAVI). Coronary artery bypass surgery (CABG) was performed on 32% and percutaneous intervention (PCI) on 11% of patients. HoFH patients have complex diseases with high morbidity and mortality, and benefit from a highly specialized multidisciplinary clinic to address their clinical needs. Although there are several therapeutic agents on the horizon, early diagnosis, and treatment of HoFH remain critical to optimize patient outcomes.

Metabolomic Approach to Screening Homozygotes in Chinese Patients with Severe Familial Hypercholesterolemia

Homozygous familial hypercholesterolemia (HoFH) is a rare inborn-errors-of-metabolism disorder characterized by devastatingly elevated low-density lipoprotein cholesterol (LDL-C) and premature cardiovascular disease. The gold standard for screening and diagnosing HoFH is genetic testing. In China, it is expensive and is always recommended for the most likely HoFH subjects with aggressive LDL-C phenotype. However, the LDL-C levels of HoFH patients and a substantial proportion of heterozygous FH (HeFH) patients overlapped considerably. Here, we performed a cost-effective metabolomic profiling on genetically diagnosed HoFH (n = 69) and HeFH patients (n = 101) with overlapping LDL-C levels, aiming to discovery a unique metabolic pattern for screening homozygotes in patients with severe FH. We demonstrated a differential serum metabolome profile in HoFH patients compared to HeFH patients. Twenty-one metabolomic alterations showed independent capability in differentiating HoFH from severe HeFH. The combined model based on seven identified metabolites yielded a corrected diagnosis in 91.3% of HoFH cases with an area under the curve value of 0.939. Collectively, this study demonstrated that metabolomic profiling serves as a useful and economical approach to preselecting homozygotes in FH patients with severe hypercholesterolemia and may help clinicians to conduct selective genetic confirmation testing and familial cascade screening.

Identifying possible homozygous familial hypercholesterolemia patients: an Italian experts' opinion

Homozygous familial hypercholesterolemia (HoFH) is a rare genetic disease characterized by high plasma levels of low-density lipoprotein cholesterol (LDL-C) and massive risk of premature atheromasia and cardiovascular events. HoFH is caused by mutations in several genes, such as LDLR, APOB, PCSK9 and LDLRAP1. If untreated, the average age of death is 18 years old, but fatalities within the first 5 years of age have been recorded. Therefore, early diagnosis and treatment are crucial, in order to prevent and/or delay the cardiovascular complications of LDL-C exposure. Because HoFH is a rare disorder, it is not frequently encountered in daily clinical practice at the primary/secondary unspecialized cardiological centers. Then the availability of practical indications helping to identify HoFH patients or to arise a suspect of HoFH is particularly strategic to promptly start the appropriate lipid-lowering therapy. For such a purpose, a group of Italian experts suggests three useful algorithms to identify cases requiring accurate and specialized clinical evaluation as potential HoFH patients. These cases with suspected HoFH should be addressed to specialized centres for the optimal management of these patients.