Plozasiran, an RNA Interference Agent Targeting APOC3, for Mixed Hyperlipidemia.

BACKGROUND: Persons with mixed hyperlipidemia are at risk for atherosclerotic cardiovascular disease due to an elevated non-high-density lipoprotein (HDL) cholesterol level, which is driven by remnant cholesterol in triglyceride-rich lipoproteins. The metabolism and clearance of triglyceride-rich lipoproteins are down-regulated through apolipoprotein C3 (APOC3)-mediated inhibition of lipoprotein lipase. METHODS: We carried out a 48-week, phase 2b, double-blind, randomized, placebo-controlled trial evaluating the safety and efficacy of plozasiran, a hepatocyte-targeted APOC3 small interfering RNA, in patients with mixed hyperlipidemia (i.e., a triglyceride level of 150 to 499 mg per deciliter and either a low-density lipoprotein [LDL] cholesterol level of ≥70 mg per deciliter or a non-HDL cholesterol level of ≥100 mg per deciliter). The participants were assigned in a 3:1 ratio to receive plozasiran or placebo within each of four cohorts. In the first three cohorts, the participants received a subcutaneous injection of plozasiran (10 mg, 25 mg, or 50 mg) or placebo on day 1 and at week 12 (quarterly doses). In the fourth cohort, participants received 50 mg of plozasiran or placebo on day 1 and at week 24 (half-yearly dose). The data from the participants who received placebo were pooled. The primary end point was the percent change in fasting triglyceride level at week 24. RESULTS: A total of 353 participants underwent randomization. At week 24, significant reductions in the fasting triglyceride level were observed with plozasiran, with differences, as compared with placebo, in the least-squares mean percent change from baseline of -49.8 percentage points (95% confidence interval [CI], -59.0 to -40.6) with the 10-mg-quarterly dose, -56.0 percentage points (95% CI, -65.1 to -46.8) with the 25-mg-quarterly dose, -62.4 percentage points (95% CI, -71.5 to -53.2) with the 50-mg-quarterly dose, and -44.2 percentage points (95% CI, -53.4 to -35.0) with the 50-mg-half-yearly dose (P<0.001 for all comparisons). Worsening glycemic control was observed in 10% of the participants receiving placebo, 12% of those receiving the 10-mg-quarterly dose, 7% of those receiving the 25-mg-quarterly dose, 20% of those receiving the 50-mg-quarterly dose, and 21% of those receiving the 50-mg-half-yearly dose. CONCLUSIONS: In this randomized, controlled trial involving participants with mixed hyperlipidemia, plozasiran, as compared with placebo, significantly reduced triglyceride levels at 24 weeks. A clinical outcomes trial is warranted. (Funded by Arrowhead Pharmaceuticals; MUIR ClinicalTrials.gov number NCT04998201.).

Zodasiran, an RNAi Therapeutic Targeting ANGPTL3, for Mixed Hyperlipidemia.

BACKGROUND: Angiopoietin-like 3 (ANGPTL3) inhibits lipoprotein and endothelial lipases and hepatic uptake of triglyceride-rich lipoprotein remnants. ANGPTL3 loss-of-function carriers have lower levels of triglycerides, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and non-HDL cholesterol and a lower risk of atherosclerotic cardiovascular disease than noncarriers. Zodasiran is an RNA interference (RNAi) therapy targeting expression of ANGPTL3 in the liver. METHODS: We conducted a double-blind, placebo-controlled, dose-ranging phase 2b trial to evaluate the safety and efficacy of zodasiran in adults with mixed hyperlipidemia (fasting triglyceride level of 150 to 499 mg per deciliter and either an LDL cholesterol level of ≥70 mg per deciliter or a non-HDL cholesterol level of ≥100 mg per deciliter). Eligible patients were randomly assigned in a 3:1 ratio to receive subcutaneous injections of zodasiran (50, 100, or 200 mg) or placebo on day 1 and week 12 and were followed through week 36. The primary end point was the percent change in the triglyceride level from baseline to week 24. RESULTS: A total of 204 patients underwent randomization. At week 24, substantial mean dose-dependent decreases from baseline in ANGPTL3 levels were observed with zodasiran (difference in change vs. placebo, -54 percentage points with 50 mg, -70 percentage points with 100 mg, and -74 percentage points with 200 mg), and significant dose-dependent decreases in triglyceride levels were observed (difference in change vs. placebo, -51 percentage points, -57 percentage points, and -63 percentage points, respectively) (P<0.001 for all comparisons). Other differences in change from baseline as compared with placebo included the following: for non-HDL cholesterol level, -29 percentage points with 50 mg, -29 percentage points with 100 mg, and -36 percentage points with 200 mg; for apolipoprotein B level, -19 percentage points, -15 percentage points, and -22 percentage points, respectively; and for LDL cholesterol level, -16 percentage points, -14 percentage points, and -20 percentage points, respectively. We observed a transient elevation in glycated hemoglobin levels in patients with preexisting diabetes who received the highest dose of zodasiran. CONCLUSIONS: In patients with mixed hyperlipidemia, zodasiran was associated with significant decreases in triglyceride levels at 24 weeks. (Funded by Arrowhead Pharmaceuticals; ARCHES-2 ClinicalTrials.gov number, NCT04832971.).

Olezarsen for Hypertriglyceridemia in Patients at High Cardiovascular Risk.

BACKGROUND: Reducing the levels of triglycerides and triglyceride-rich lipoproteins remains an unmet clinical need. Olezarsen is an antisense oligonucleotide targeting messenger RNA for apolipoprotein C-III (APOC3), a genetically validated target for triglyceride lowering. METHODS: In this phase 2b, randomized, controlled trial, we assigned adults either with moderate hypertriglyceridemia (triglyceride level, 150 to 499 mg per deciliter) and elevated cardiovascular risk or with severe hypertriglyceridemia (triglyceride level, ≥500 mg per deciliter) in a 1:1 ratio to either a 50-mg or 80-mg cohort. Patients were then assigned in a 3:1 ratio to receive monthly subcutaneous olezarsen or matching placebo within each cohort. The primary outcome was the percent change in the triglyceride level from baseline to 6 months, reported as the difference between each olezarsen group and placebo. Key secondary outcomes were changes in levels of APOC3, apolipoprotein B, non-high-density lipoprotein (HDL) cholesterol, and low-density lipoprotein (LDL) cholesterol. RESULTS: A total of 154 patients underwent randomization at 24 sites in North America. The median age of the patients was 62 years, and the median triglyceride level was 241.5 mg per deciliter. The 50-mg and 80-mg doses of olezarsen reduced triglyceride levels by 49.3 percentage points and 53.1 percentage points, respectively, as compared with placebo (P<0.001 for both comparisons). As compared with placebo, each dose of olezarsen also significantly reduced the levels of APOC3, apolipoprotein B, and non-HDL cholesterol, with no significant change in the LDL cholesterol level. The risks of adverse events and serious adverse events were similar in the three groups. Clinically meaningful hepatic, renal, or platelet abnormalities were uncommon, with similar risks in the three groups. CONCLUSIONS: In patients with predominantly moderate hypertriglyceridemia at elevated cardiovascular risk, olezarsen significantly reduced levels of triglycerides, apolipoprotein B, and non-HDL cholesterol, with no major safety concerns identified. (Funded by Ionis Pharmaceuticals; Bridge-TIMI 73a ClinicalTrials.gov number, NCT05355402.).

Small Interfering RNA to Reduce Lipoprotein(a) in Cardiovascular Disease.

BACKGROUND: Lipoprotein(a) is a presumed risk factor for atherosclerotic cardiovascular disease. Olpasiran is a small interfering RNA that reduces lipoprotein(a) synthesis in the liver. METHODS: We conducted a randomized, double-blind, placebo-controlled, dose-finding trial involving patients with established atherosclerotic cardiovascular disease and a lipoprotein(a) concentration of more than 150 nmol per liter. Patients were randomly assigned to receive one of four doses of olpasiran (10 mg every 12 weeks, 75 mg every 12 weeks, 225 mg every 12 weeks, or 225 mg every 24 weeks) or matching placebo, administered subcutaneously. The primary end point was the percent change in the lipoprotein(a) concentration from baseline to week 36 (reported as the placebo-adjusted mean percent change). Safety was also assessed. RESULTS: Among the 281 enrolled patients, the median concentration of lipoprotein(a) at baseline was 260.3 nmol per liter, and the median concentration of low-density lipoprotein cholesterol was 67.5 mg per deciliter. At baseline, 88% of the patients were taking statin therapy, 52% were taking ezetimibe, and 23% were taking a proprotein convertase subtilisin-kexin type 9 (PCSK9) inhibitor. At 36 weeks, the lipoprotein(a) concentration had increased by a mean of 3.6% in the placebo group, whereas olpasiran therapy had significantly and substantially reduced the lipoprotein(a) concentration in a dose-dependent manner, resulting in placebo-adjusted mean percent changes of -70.5% with the 10-mg dose, -97.4% with the 75-mg dose, -101.1% with the 225-mg dose administered every 12 weeks, and -100.5% with the 225-mg dose administered every 24 weeks (P<0.001 for all comparisons with baseline). The overall incidence of adverse events was similar across the trial groups. The most common olpasiran-related adverse events were injection-site reactions, primarily pain. CONCLUSIONS: Olpasiran therapy significantly reduced lipoprotein(a) concentrations in patients with established atherosclerotic cardiovascular disease. Longer and larger trials will be necessary to determine the effect of olpasiran therapy on cardiovascular disease. (Funded by Amgen; OCEAN[a]-DOSE ClinicalTrials.gov number, NCT04270760.).

Evolocumab Treatment in Pediatric Patients With Homozygous Familial Hypercholesterolemia: Pooled Data From Three Open-Label Studies.

BACKGROUND: Pediatric patients with homozygous familial hypercholesterolemia (HoFH) have an increased risk of atherosclerotic cardiovascular disease and difficulty meeting low-density lipoprotein cholesterol (LDL-C) goals. In this post hoc analysis, we evaluated pooled safety and efficacy data from 3 studies in pediatric patients with HoFH treated with the PCSK9 (proprotein convertase subtilisin/kexin type 9) monoclonal antibody inhibitor evolocumab. METHODS: Patients with HoFH aged 10 to 17 years received treatment with open-label evolocumab 420 mg subcutaneously monthly or biweekly in the TAUSSIG, RAMAN, or HAUSER-OLE clinical studies. All patients received background statins with or without ezetimibe. Study duration ranged from 12 to 260 weeks. The primary end point was treatment-emergent adverse events per 100 patient-years. Efficacy end points were changes from baseline to week 12 in lipids and PCSK9. RESULTS: Of the 39 patients in the pooled analysis, 69.2% were males, median age was 13.0 years, and 79.5% (31/39) had genotyped HoFH with LDLR pathogenic variants. Overall, median exposure to evolocumab was 18.2 (Q1, Q3: 3.0, 18.5) months. Treatment-emergent adverse events with an exposure-adjusted patient incidence rate of ≥5% were upper respiratory tract infection (6.6%), influenza (5.2%), and acne (5.0%) per 100 patient-years. Exposure-adjusted patient incidence of serious treatment-emergent adverse events was 13.3% per 100 patient-years. Excluding 4 patients receiving lipoprotein apheresis, week 12 median percentage change from baseline in LDL-C was -2.9% (Q1, Q3: -21.7, 1.5); however, 42.9% (15/35) of patients achieved ≥15% reduction in LDL-C from baseline. Residual LDLR (LDL receptor) activity was not associated with a reduction in LDL-C. CONCLUSIONS: In this pooled data analysis from 3 studies in pediatric patients with HoFH, evolocumab was well tolerated, with no new safety signals reported. These safety findings are consistent with findings from previous studies of evolocumab. Patients showed marked variability in LDL-C reduction. Results from this pooled analysis support guidelines suggesting a trial of PCSK9 inhibitor therapy regardless of estimated residual LDLR function. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01624142, NCT03403374, and NCT02624869.

Evinacumab in homozygous familial hypercholesterolaemia: long-term safety and efficacy.

BACKGROUND AND AIMS: Homozygous familial hypercholesterolaemia (HoFH) is a rare genetic disorder characterized by severely elevated LDL cholesterol (LDL-C) and premature atherosclerotic cardiovascular disease. In the pivotal Phase 3 HoFH trial (NCT03399786), evinacumab significantly decreased LDL-C in patients with HoFH. This study assesses the long-term safety and efficacy of evinacumab in adult and adolescent patients with HoFH. METHODS: In this open-label, single-arm, Phase 3 trial (NCT03409744), patients aged ≥12 years with HoFH who were evinacumab-naïve or had previously received evinacumab in other trials (evinacumab-continue) received intravenous evinacumab 15 mg/kg every 4 weeks with stable lipid-lowering therapy. RESULTS: A total of 116 patients (adults: n = 102; adolescents: n = 14) were enrolled, of whom 57 (49.1%) were female. Patients were treated for a median (range) duration of 104.3 (28.3-196.3) weeks. Overall, treatment-emergent adverse events (TEAEs) and serious TEAEs were reported in 93 (80.2%) and 27 (23.3%) patients, respectively. Two (1.7%) deaths were reported (neither was considered related to evinacumab). Three (2.6%) patients discontinued due to TEAEs (none were considered related to evinacumab). From baseline to Week 24, evinacumab decreased mean LDL-C by 43.6% [mean (standard deviation, SD), 3.4 (3.2) mmol/L] in the overall population; mean LDL-C reduction in adults and adolescents was 41.7% [mean (SD), 3.2 (3.3) mmol/L] and 55.4% [mean (SD), 4.7 (2.5) mmol/L], respectively. CONCLUSIONS: In this large cohort of patients with HoFH, evinacumab was generally well tolerated and markedly decreased LDL-C irrespective of age and sex. Moreover, the efficacy and safety of evinacumab was sustained over the long term.

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.

Evinacumab in Patients with Refractory Hypercholesterolemia.

BACKGROUND: Patients with refractory hypercholesterolemia, who have high low-density lipoprotein (LDL) cholesterol levels despite treatment with lipid-lowering therapies at maximum tolerated doses, have an increased risk of atherosclerosis. In such patients, the efficacy and safety of subcutaneous and intravenous evinacumab, a fully human monoclonal antibody against angiopoietin-like 3, are not known. METHODS: In this double-blind, placebo-controlled, phase 2 trial, we enrolled patients with or without heterozygous familial hypercholesterolemia who had refractory hypercholesterolemia, with a screening LDL cholesterol level of 70 mg per deciliter or higher with atherosclerosis or of 100 mg per deciliter or higher without atherosclerosis. Patients were randomly assigned to receive subcutaneous or intravenous evinacumab or placebo. The primary end point was the percent change from baseline in the LDL cholesterol level at week 16 with evinacumab as compared with placebo. RESULTS: In total, 272 patients were randomly assigned to the following groups: subcutaneous evinacumab at a dose of 450 mg weekly (40 patients), 300 mg weekly (43 patients), or 300 mg every 2 weeks (39 patients) or placebo (41 patients); or intravenous evinacumab at a dose of 15 mg per kilogram of body weight every 4 weeks (39 patients) or 5 mg per kilogram every 4 weeks (36 patients) or placebo (34 patients). At week 16, the differences in the least-squares mean change from baseline in the LDL cholesterol level between the groups assigned to receive subcutaneous evinacumab at a dose of 450 mg weekly, 300 mg weekly, and 300 mg every 2 weeks and the placebo group were -56.0, -52.9, and -38.5 percentage points, respectively (P<0.001 for all comparisons). The differences between the groups assigned to receive intravenous evinacumab at a dose of 15 mg per kilogram and 5 mg per kilogram and the placebo group were -50.5 percentage points (P<0.001) and -24.2 percentage points, respectively. The incidence of serious adverse events during the treatment period ranged from 3 to 16% across trial groups. CONCLUSIONS: In patients with refractory hypercholesterolemia, the use of evinacumab significantly reduced the LDL cholesterol level, by more than 50% at the maximum dose. (Funded by Regeneron Pharmaceuticals; ClinicalTrials.gov number, NCT03175367.).

Evolocumab in Pediatric Heterozygous Familial Hypercholesterolemia.

BACKGROUND: Evolocumab, a fully human monoclonal antibody directed against proprotein convertase subtilisin-kexin type 9, is widely used in adult patients to lower low-density lipoprotein (LDL) cholesterol levels. Its effects in pediatric patients with heterozygous familial hypercholesterolemia are not known. METHODS: We conducted a 24-week, randomized, double-blind, placebo-controlled trial to evaluate the efficacy and safety of evolocumab in pediatric patients with heterozygous familial hypercholesterolemia. Patients 10 to 17 years of age who had received stable lipid-lowering treatment for at least 4 weeks before screening and who had an LDL cholesterol level of 130 mg per deciliter (3.4 mmol per liter) or more and a triglyceride level of 400 mg per deciliter (4.5 mmol per liter) or less were randomly assigned in a 2:1 ratio to receive monthly subcutaneous injections of evolocumab (420 mg) or placebo. The primary end point was the percent change in LDL cholesterol level from baseline to week 24; key secondary end points were the mean percent change in LDL cholesterol level from baseline to weeks 22 and 24 and the absolute change in LDL cholesterol level from baseline to week 24. RESULTS: A total of 157 patients underwent randomization and received evolocumab (104 patients) or placebo (53 patients). At week 24, the mean percent change from baseline in LDL cholesterol level was -44.5% in the evolocumab group and -6.2% in the placebo group, for a difference of -38.3 percentage points (P<0.001). The absolute change in the LDL cholesterol level was -77.5 mg per deciliter (-2.0 mmol per liter) in the evolocumab group and -9.0 mg per deciliter (-0.2 mmol per liter) in the placebo group, for a difference of -68.6 mg per deciliter (-1.8 mmol per liter) (P<0.001). Results for all secondary lipid variables were significantly better with evolocumab than with placebo. The incidence of adverse events that occurred during the treatment period was similar in the evolocumab and placebo groups. CONCLUSIONS: In this trial involving pediatric patients with familial hypercholesterolemia, evolocumab reduced the LDL cholesterol level and other lipid variables. (Funded by Amgen; HAUSER-RCT ClinicalTrials.gov number, NCT02392559.).

Evinacumab for Homozygous Familial Hypercholesterolemia.

BACKGROUND: Homozygous familial hypercholesterolemia is characterized by premature cardiovascular disease caused by markedly elevated levels of low-density lipoprotein (LDL) cholesterol. This disorder is associated with genetic variants that result in virtually absent (null-null) or impaired (non-null) LDL-receptor activity. Loss-of-function variants in the gene encoding angiopoietin-like 3 (ANGPTL3) are associated with hypolipidemia and protection against atherosclerotic cardiovascular disease. Evinacumab, a monoclonal antibody against ANGPTL3, has shown potential benefit in patients with homozygous familial hypercholesterolemia. METHODS: In this double-blind, placebo-controlled, phase 3 trial, we randomly assigned in a 2:1 ratio 65 patients with homozygous familial hypercholesterolemia who were receiving stable lipid-lowering therapy to receive an intravenous infusion of evinacumab (at a dose of 15 mg per kilogram of body weight) every 4 weeks or placebo. The primary outcome was the percent change from baseline in the LDL cholesterol level at week 24. RESULTS: The mean baseline LDL cholesterol level in the two groups was 255.1 mg per deciliter, despite the receipt of maximum doses of background lipid-lowering therapy. At week 24, patients in the evinacumab group had a relative reduction from baseline in the LDL cholesterol level of 47.1%, as compared with an increase of 1.9% in the placebo group, for a between-group least-squares mean difference of -49.0 percentage points (95% confidence interval [CI], -65.0 to -33.1; P<0.001); the between-group least-squares mean absolute difference in the LDL cholesterol level was -132.1 mg per deciliter (95% CI, -175.3 to -88.9; P<0.001). The LDL cholesterol level was lower in the evinacumab group than in the placebo group in patients with null-null variants (-43.4% vs. +16.2%) and in those with non-null variants (-49.1% vs. -3.8%). Adverse events were similar in the two groups. CONCLUSIONS: In patients with homozygous familial hypercholesterolemia receiving maximum doses of lipid-lowering therapy, the reduction from baseline in the LDL cholesterol level in the evinacumab group, as compared with the small increase in the placebo group, resulted in a between-group difference of 49.0 percentage points at 24 weeks. (Funded by Regeneron Pharmaceuticals; ELIPSE HoFH ClinicalTrials.gov number, NCT03399786.).

Inhibition of Angiopoietin-Like Protein 3 or 3/8 Complex and ApoC-III in Severe Hypertriglyceridemia.

PURPOSE OF REVIEW: The role of the inhibition of ANGPTL3 in severe or refractory hypercholesterolemia is well documented, less in severe hyperTG. This review focuses on the preclinical and clinical development of ApoC-III inhibitors and ANGPTL3, 4, and 3/8 complex inhibitors for the treatment of severe or refractory forms of hypertriglyceridemia to prevent cardiovascular disease or other morbidities. RECENT FINDINGS: APOC3 and ANGPTL3 became targets for drug development following the identification of naturally occurring loss of function variants in families with a favorable lipid profile and low cardiovascular risk. The inhibition of ANGPTL3 covers a broad spectrum of lipid disorders from severe hypercholesterolemia to severe hypertriglyceridemia, while the inhibition of ApoC-III can treat hypertriglyceridemia regardless of the severity. Preclinical and clinical data suggest that ApoC-III inhibitors, ANGPTL3 inhibitors, and inhibitors of the ANGPTL3/8 complex that is formed postprandially are highly effective for the treatment of severe or refractory hypertriglyceridemia. Inhibition of ANGPTL3 or the ANGPTL3/8 complex upregulates LPL and facilitates the hydrolysis and clearance of triglyceride-rich lipoproteins (TRL) (LPL-dependent mechanisms), whereas ApoC-III inhibitors contribute to the management and clearance of TRL through both LPL-dependent and LPL-independent mechanisms making it possible to successfully lower TG in subjects completely lacking LPL (familial chylomicronemia syndrome). Most of these agents are biologicals including monoclonal antibodies (mAb), antisense nucleotides (ASO), small interfering RNA (siRNA), or CRISPR-cas gene editing strategies.

Apolipoprotein C-III reduction in subjects with moderate hypertriglyceridaemia and at high cardiovascular risk.

AIMS: Hypertriglyceridaemia is associated with increased risk of cardiovascular events. This clinical trial evaluated olezarsen, an N-acetyl-galactosamine-conjugated antisense oligonucleotide targeted to hepatic APOC3 mRNA to inhibit apolipoprotein C-III (apoC-III) production, in lowering triglyceride levels in patients at high risk for or with established cardiovascular disease. METHODS AND RESULTS: A randomized, double-blind, placebo-controlled, dose-ranging study was conducted in 114 patients with fasting serum triglycerides 200-500 mg/dL (2.26-5.65 mmol/L). Patients received olezarsen (10 or 50 mg every 4 weeks, 15 mg every 2 weeks, or 10 mg every week) or saline placebo subcutaneously for 6-12 months. The primary endpoint was the percent change in fasting triglyceride levels from baseline to Month 6 of exposure. Baseline median (interquartile range) fasting triglyceride levels were 262 (222-329) mg/dL [2.96 (2.51-3.71) mmol/L]. Treatment with olezarsen resulted in mean percent triglyceride reductions of 23% with 10 mg every 4 weeks, 56% with 15 mg every 2 weeks, 60% with 10 mg every week, and 60% with 50 mg every 4 weeks, compared with increase by 6% for the pooled placebo group (P-values ranged from 0.0042 to <0.0001 compared with placebo). Significant decreases in apoC-III, very low-density lipoprotein cholesterol, non-high-density lipoprotein cholesterol, and apolipoprotein B were also observed. There were no platelet count, liver, or renal function changes in any of the olezarsen groups. The most common adverse event was mild erythema at the injection site. CONCLUSION: Olezarsen significantly reduced apoC-III, triglycerides, and atherogenic lipoproteins in patients with moderate hypertriglyceridaemia and at high risk for or with established cardiovascular disease. TRIAL REGISTRATION NUMBER: NCT03385239.

Volanesorsen and Triglyceride Levels in Familial Chylomicronemia Syndrome.

BACKGROUND: Familial chylomicronemia syndrome is a rare genetic disorder that is caused by loss of lipoprotein lipase activity and characterized by chylomicronemia and recurrent episodes of pancreatitis. There are no effective therapies. In an open-label study of three patients with this syndrome, antisense-mediated inhibition of hepatic APOC3 mRNA with volanesorsen led to decreased plasma apolipoprotein C-III and triglyceride levels. METHODS: We conducted a phase 3, double-blind, randomized 52-week trial to evaluate the safety and effectiveness of volanesorsen in 66 patients with familial chylomicronemia syndrome. Patients were randomly assigned, in a 1:1 ratio, to receive volanesorsen or placebo. The primary end point was the percentage change in fasting triglyceride levels from baseline to 3 months. RESULTS: Patients receiving volanesorsen had a decrease in mean plasma apolipoprotein C-III levels from baseline of 25.7 mg per deciliter, corresponding to an 84% decrease at 3 months, whereas patients receiving placebo had an increase in mean plasma apolipoprotein C-III levels from baseline of 1.9 mg per deciliter, corresponding to a 6.1% increase (P<0.001). Patients receiving volanesorsen had a 77% decrease in mean triglyceride levels, corresponding to a mean decrease of 1712 mg per deciliter (19.3 mmol per liter) (95% confidence interval [CI], 1330 to 2094 mg per deciliter [15.0 to 23.6 mmol per liter]), whereas patients receiving placebo had an 18% increase in mean triglyceride levels, corresponding to an increase of 92.0 mg per deciliter (1.0 mmol per liter) (95% CI, -301.0 to 486 mg per deciliter [-3.4 to 5.5 mmol per liter]) (P<0.001). At 3 months, 77% of the patients in the volanesorsen group, as compared with 10% of patients in the placebo group, had triglyceride levels of less than 750 mg per deciliter (8.5 mmol per liter). A total of 20 of 33 patients who received volanesorsen had injection-site reactions, whereas none of the patients who received placebo had such reactions. No patients in the placebo group had platelet counts below 100,000 per microliter, whereas 15 of 33 patients in the volanesorsen group had such levels, including 2 who had levels below 25,000 per microliter. No patient had platelet counts below 50,000 per microliter after enhanced platelet-monitoring began. CONCLUSIONS: Volanesorsen lowered triglyceride levels to less than 750 mg per deciliter in 77% of patients with familial chylomicronemia syndrome. Thrombocytopenia and injection-site reactions were common adverse events. (Funded by Ionis Pharmaceuticals and Akcea Therapeutics; APPROACH Clinical Trials.gov number, NCT02211209.).

A variant near DHCR24 associates with microstructural properties of white matter and peripheral lipid metabolism in adolescents.

Visceral adiposity has been associated with altered microstructural properties of white matter in adolescents. Previous evidence suggests that circulating phospholipid PC(16:0/2:0) may mediate this association. To investigate the underlying biology, we performed a genome-wide association study (GWAS) of the shared variance of visceral fat, PC(16:0/2:0), and white matter microstructure in 872 adolescents from the Saguenay Youth Study. We further studied the metabolomic profile of the GWAS-lead variant in 931 adolescents. Visceral fat and white matter microstructure were assessed with magnetic resonance imaging. Circulating metabolites were quantified with serum lipidomics and metabolomics. We identified a genome-wide significant association near DHCR24 (Seladin-1) encoding a cholesterol-synthesizing enzyme (rs588709, p = 3.6 × 10-8); rs588709 was also associated nominally with each of the three traits (white matter microstructure: p = 2.1 × 10-6, PC(16:0/2:0): p = 0.005, visceral fat: p = 0.010). We found that the metabolic profile associated with rs588709 resembled that of a TM6SF2 variant impacting very low-density lipoprotein (VLDL) secretion and was only partially similar to that of a HMGCR variant. This suggests that the effect of rs588709 on VLDL lipids may arise due to altered phospholipid rather than cholesterol metabolism. The rs588709 was also nominally associated with circulating concentrations of omega-3 fatty acids in interaction with visceral fat and PC(16:0/2:0), and these fatty acid measures showed robust associations with white matter microstructure. Overall, the present study provides evidence that the DHCR24 locus may link peripheral metabolism to brain microstructure, an association with implications for cognitive impairment.

Genetic burden linked to founder effects in Saguenay-Lac-Saint-Jean illustrates the importance of genetic screening test availability.

The Saguenay-Lac-Saint-Jean (SLSJ) region located in the province of Quebec was settled in the 19th century by pioneers issued from successive migration waves starting in France in the 17th century and continuing within Quebec until the beginning of the 20th century. The genetic structure of the SLSJ population is considered to be the product of a triple founder effect and is characterised by a higher prevalence of some rare genetic diseases. Several studies were performed to elucidate the historical, demographic and genetic background of current SLSJ inhabitants to assess the origins of these rare disorders and their distribution in the population. Thanks to the development of new sequencing technologies, the genes and the variants responsible for the most prevalent conditions were identified. Combined with other resources such as the BALSAC population database, identifying the causal genes and the pathogenic variants allowed to assess the impacts of some of these founder mutations on the population health and to design precision medicine public health strategies based on carrier testing. Furthermore, it stimulated the establishment of many public programmes.We report here a review and an update of a subset of inherited disorders and founder mutations in the SLSJ region. Data were collected from published scientific sources. This work expands the knowledge about the current frequencies of these rare disorders, the frequencies of other rare genetic diseases in this population, the relevance of the carrier tests offered to the population, as well as the current available treatments and research about future therapeutic avenues for these inherited disorders.

Triglyceride-rich lipoproteins and their remnants: metabolic insights, role in atherosclerotic cardiovascular disease, and emerging therapeutic strategies-a consensus statement from the European Atherosclerosis Society.

Recent advances in human genetics, together with a large body of epidemiologic, preclinical, and clinical trial results, provide strong support for a causal association between triglycerides (TG), TG-rich lipoproteins (TRL), and TRL remnants, and increased risk of myocardial infarction, ischaemic stroke, and aortic valve stenosis. These data also indicate that TRL and their remnants may contribute significantly to residual cardiovascular risk in patients on optimized low-density lipoprotein (LDL)-lowering therapy. This statement critically appraises current understanding of the structure, function, and metabolism of TRL, and their pathophysiological role in atherosclerotic cardiovascular disease (ASCVD). Key points are (i) a working definition of normo- and hypertriglyceridaemic states and their relation to risk of ASCVD, (ii) a conceptual framework for the generation of remnants due to dysregulation of TRL production, lipolysis, and remodelling, as well as clearance of remnant lipoproteins from the circulation, (iii) the pleiotropic proatherogenic actions of TRL and remnants at the arterial wall, (iv) challenges in defining, quantitating, and assessing the atherogenic properties of remnant particles, and (v) exploration of the relative atherogenicity of TRL and remnants compared to LDL. Assessment of these issues provides a foundation for evaluating approaches to effectively reduce levels of TRL and remnants by targeting either production, lipolysis, or hepatic clearance, or a combination of these mechanisms. This consensus statement updates current understanding in an integrated manner, thereby providing a platform for new therapeutic paradigms targeting TRL and their remnants, with the aim of reducing the risk of ASCVD.

Vupanorsen, an N-acetyl galactosamine-conjugated antisense drug to ANGPTL3 mRNA, lowers triglycerides and atherogenic lipoproteins in patients with diabetes, hepatic steatosis, and hypertriglyceridaemia.

AIMS: Loss-of-function mutations in ANGPTL3 are associated with beneficial effects on lipid and glucose metabolism and reduced risk of coronary artery disease. Vupanorsen (AKCEA-ANGPTL3-L Rx ) is an N-acetyl galactosamine-conjugated antisense oligonucleotide targeted to the liver that selectively inhibits angiopoietin-like 3 (ANGPTL3) protein synthesis. METHODS AND RESULTS: This was a double-blind, placebo-controlled, dose-ranging, Phase 2 study. Patients (N =105) with fasting triglycerides >150 mg/dL (>1.7 mmol/L), type 2 diabetes, and hepatic steatosis were treated for 6 months with 40 or 80 mg every 4 weeks (Q4W), or 20 mg every week (QW) of vupanorsen, or placebo given subcutaneously. The primary efficacy endpoint was per cent change in fasting triglycerides from baseline at 6 months. Median baseline triglycerides were 2.84 mmol/L (252 mg/dL). Significant reductions in triglycerides of 36%, 53%, 47%, and in ANGPTL3 of 41%, 59%, 56%, were observed in the 40 mg Q4W, 80 mg Q4W, and 20 mg QW groups, respectively, compared with 16% reduction in triglycerides and 8% increase in ANGPTL3 in placebo. Compared with placebo, vupanorsen 80 mg Q4W reduced apolipoprotein C-III (58%), remnant cholesterol (38%), total cholesterol (19%), non-high-density lipoprotein cholesterol (HDL-C; 18%), HDL-C (24%), and apolipoprotein B (9%). There was no improvement in glycaemic parameters, or hepatic fat fraction. Treatment with vupanorsen was not associated with clinically significant changes in platelet counts, and the most common adverse events were those at the injection site, which were generally mild. CONCLUSION: Vupanorsen results in a favourable lipid/lipoprotein profile and provides a potential strategy for residual cardiovascular risk reduction.

Functional Analysis of LDLR (Low-Density Lipoprotein Receptor) Variants in Patient Lymphocytes to Assess the Effect of Evinacumab in Homozygous Familial Hypercholesterolemia Patients With a Spectrum of LDLR Activity.

OBJECTIVE: Homozygous familial hypercholesterolemia is a rare disease usually caused by LDLR (low-density lipoprotein receptor) mutations. Homozygous familial hypercholesterolemia is characterized by markedly elevated LDL-C (low-density lipoprotein cholesterol) levels and an extremely high risk of premature atherosclerotic cardiovascular disease. A phase 2, proof-of-concept study (NCT02265952) demonstrated that evinacumab, a fully human monoclonal antibody to ANGPTL3 (angiopoietin-like 3 protein), reduced LDL-C levels in 9 patients with genotypically confirmed homozygous familial hypercholesterolemia and was well tolerated. The aim of this study was to analyze the effects of evinacumab on LDLR activity in lymphocytes purified from patients in the proof-of-concept study. Approach and Results: LDLR activity was assessed in patient lymphocytes before and after treatment with evinacumab and versus lymphocytes carrying wild-type LDLR, and also in an LDLR-defective Chinese hamster ovary cell line (CHO-ldlA7) transfected with plasmids encoding the LDLR variants. Overall mean peak reduction in LDL-C with evinacumab was -58±18%, occurring between Week 4 and Week 12. Mutations identified in the 9 patients were shown to be pathogenic, with loss of LDLR activity versus wild type. Two of the LDLR variants, p.(Cys681*) and p.(Ala627Profs*38), were class 2 type mutations that are retained in the endoplasmic reticulum. Six variants were class 3 type mutations with impaired LDL-C binding activity: p.(Trp87Gly), occurring in 2 patients, p.(Gln254Pro), p.(Ser177Leu), p.(Gly335Val), and p.(Ser306Leu). Evinacumab had no effect on LDLR activity. CONCLUSIONS: These results suggest that evinacumab is effective for lowering LDL-C in patients with homozygous familial hypercholesterolemia, and the inhibition of ANGPTL3 in humans lowers LDL-C in a mechanism independent of the LDLR.

Association of common gene-smoking interactions with elevated plasma apolipoprotein B concentration.

BACKGROUND: Increased apolipoprotein (apo) B level (hyperapoB) is a strong predictor of cardiovascular disease (CVD), even in patients who achieve recommended LDL-Cholesterol (LDL-C) goals. ApoB level, an important correlate of metabolic syndrome (MetS), is influenced by several gene-environment interactions. Some of them are rare and can explain a large proportion of apoB variance, whereas others more common have variable effects. The aim of this study was to evaluate the association of interaction between smoking and common hyperapoB gene variants (PPARα-L162V, lipoprotein lipase loss-of function mutation, apo e4 allele or apo E2/2 genotype) with plasma apoB concentrations, according to the expression of MetS. METHODS: This study was performed among 1798 subjects. Smoking was defined as non/mild smokers vs. moderate-to-heavy smokers. ApoB levels were determined using nephelometry. Logistic regression models were used to document interactions between smoking habits and the presence of hyperapoB gene variants on the relative odds to exhibit increased plasma apoB concentrations. RESULTS: Around 29% of individuals with a low-risk lipid profile without MetS component had hyperapoB. Smoking and the presence of hyperapoB gene variants tended to be associated with higher plasma apoB levels even in presence of low-LDL-C. There was a significant interaction (P = 0.04) between the presence of ≥1 gene variants and smoking on the risk to exhibit hyperapoB among subjects with low risk profile in primary prevention. CONCLUSIONS: Combination of life habits assessment and some common genes variants may detect a significant proportion of patients with increased apoB levels, and therefore a higher risk of CVD, who could have been initially perceived as low-risk.

The burden of familial chylomicronemia syndrome in Canadian patients.

BACKGROUND: Familial chylomicronemia syndrome (FCS) is a rare autosomal recessive disorder characterized by persistent extreme hypertriglyceridemia as a result of lipoprotein lipase deficiency. Canada is an important region for FCS research due to the high prevalence rates. The burden of illness and quality of life of Canadian patients, however, have been inadequately addressed in the literature. OBJECTIVE: To understand the burden of illness of FCS on Canadian patients' lives. METHODS: IN-FOCUS is a global web-based survey open to patients with FCS, including patients in Canada. This survey captured information on diagnostic experience, symptoms, comorbidities, disease management, and impact on multiple life dimensions. RESULTS: A total of 37 Canadian patients completed the IN-FOCUS survey. Patients saw a mean of 4 physicians before their FCS diagnosis despite 89% reporting an FCS family history. Patients experience multiple physical, emotional, and cognitive symptoms in addition to FCS-related comorbidities. Notably, 35% of those who answered the survey have experienced acute pancreatitis, averaging 14 lifetime episodes per patient. In the preceding 12 months, 46% of patients had an FCS-related hospitalization, averaging 3 nights' stay. All respondents restricted fat intake, with 27% following an extremely low-fat diet. Despite this, 100% of patients reported fasting TG levels above the normal range. FCS impacted career choice in nearly all patients (97%) and employment status in all patients who were employed part time, disabled, or homemakers, causing many (> 75%) to choose careers below their level of abilities. Furthermore, 2/3 of patients reported FCS had a significant impact on their decision regarding whether to have children. Most report significant interference with their emotional/mental well-being, social relationships, and the majority were concerned about the long-term impact of FCS on their health (89%). CONCLUSIONS: This study provides the first and largest study to investigate the multi-faceted psychosocial and cognitive impacts of FCS on patients. Canadian patients with FCS experience significant multi-faceted burdens that diminish their quality of life, employment opportunities, social relationships, and mental/emotional well-being. These results highlight the need for greater disease awareness, improved clinical diagnosis, broader clinical management for heterogenous symptoms, and more effective treatment options for FCS.