Profiling Sterols in Cerebrotendinous Xanthomatosis: Utility of Girard Derivatization and High Resolution Exact Mass LC-ESI-MSn Analysis

In this study we profile free 3-oxo sterols present in plasma from patients affected with the neurodegenerative disorder of sterol and bile acid metabolism cerebrotendinous xanthomatosis (CTX), utilizing a combination of charge-tagging and LC-ESI-MSn performed with an LTQ-Orbitrap Discovery instrument. In addition, we profile sterols in plasma from 24-month-old cyp27A1 gene knockout mice lacking the enzyme defective in CTX. Charge-tagging was accomplished by reaction with cationic Girard\u27s P (GP) reagent 1-(carboxymethyl) pyridinium chloride hydrazide, an approach uniquely suited to studying the 3-oxo sterols that accumulate in CTX, as Girard\u27s reagent reacts with the sterol oxo moiety to form charged hydrazone derivatives. The ability to selectively generate GP-tagged 3-oxo-4-ene and 3-oxo-5(H) saturated plasma sterols enabled ESI-MSn analysis of these sterols in the presence of a large excess (3 orders of magnitude) of cholesterol. Often cholesterol detected in biological samples makes it challenging to quantify minor sterols, with cholesterol frequently removed prior to analysis. We derivatized plasma (10μl) without SPE removal of cholesterol to ensure detection of all sterols present in plasma. We were able to measure 4-cholesten-3-one in plasma from untreated CTX patients (1207±302ng/ml, mean±SD, n=4), as well as other intermediates in a proposed pathway to 5α-cholestanol. In addition, a number of bile acid precursors were identified in plasma using this technique. GP-tagged sterols were identified utilizing high resolution exact mass spectra (±5ppm), as well as MS2 ([M]+→) spectra that possessed characteristic neutral loss of 79Da (pyridine) fragment ions, and MS3 ([M]+→[M-79]+→) spectra that provided additional structurally informative fragment ions. © 2010 Elsevier B.V

Efficacy and safety of bempedoic acid in patients not receiving statins in phase 3 clinical trials

BACKGROUND: Despite the high incidence of patients with statin tolerance problems, randomized evaluations of nonstatin oral treatment options for lowering of low-density lipoprotein cholesterol (LDL-C) in this population are sparse. OBJECTIVE: To assess the LDL-C lowering effect of bempedoic acid in patients not taking statins. METHODS: This was a pooled analysis of data from patients enrolled in four phase 3 bempedoic acid studies (12 to 52 weeks in duration) who were not taking concomitant statins (Phase 3 No Statin Cohort) and a phase 3 bempedoic acid plus ezetimibe fixed-dose combination study (BA+EZE FDC No Statin Cohort). The primary endpoint for all studies was the percent change from baseline to week 12 in LDL-C levels. Safety and tolerability were assessed by laboratory values and adverse events. RESULTS: In the Phase 3 No Statin Cohort, bempedoic acid (n = 394) lowered LDL-C levels at week 12 significantly more than placebo (n = 192; -26.5% [95% CI, -29.7%, -23.2%]; P\u3c0.001). The fixed-dose combination of bempedoic acid with ezetimibe lowered LDL-C by 39.2% (95% CI, -51.7% to -26.7%; P\u3c0.001). Muscle-related disorders occurred at a rate of 26.4 and 28.6 per 100 person-years with bempedoic acid and placebo, respectively. CONCLUSIONS: In patients with hypercholesterolemia unable to take statins, bempedoic acid lowered LDL-C levels by a mean of 26.5% vs placebo and bempedoic acid + ezetimibe fixed-dose combination lowered LDL-C by 39.2%. The treatments were generally well tolerated, suggesting that bempedoic acid may be efficacious and well tolerated in this challenging-to-treat patient population

Bempedoic acid safety analysis: Pooled data from four phase 3 clinical trials

Background An ongoing need exists for safe and effective lipid-lowering therapies (LLTs) for patients unable to achieve desired lipid levels with current treatment options. Objective The objective of this study was to describe the safety profile of bempedoic acid, an oral, first-in-class, adenosine triphosphate (ATP)–citrate lyase inhibitor that significantly reduces low-density lipoprotein cholesterol (LDL-C) levels by 17.4%–28.5% vs placebo. Methods This was a pooled analysis of four phase 3, randomized (2:1), double-blind, placebo-controlled studies in patients with hypercholesterolemia who required additional LDL-C lowering, despite stable maximally-tolerated LLT. Patients received 180 mg of bempedoic acid (n = 2424) or placebo (n = 1197) once daily for 12 to 52 weeks. Assessments included treatment-emergent adverse events (TEAEs) and clinical laboratory tests. Results Of 3621 patients (the median drug exposure: 363 days), exposure-adjusted TEAE rates were 87.1/100 and 82.9/100 person-years (PY) for bempedoic acid and placebo, respectively. No single TEAE influenced the difference in rates. TEAEs leading to discontinuation occurred at rates of 13.4/100 and 8.9/100 PY for bempedoic acid vs placebo, with the most common cause being myalgia, which occurred less frequently with bempedoic acid vs placebo (1.5/100 vs 2.0/100 PY). Rates of myalgia and muscle weakness were comparable vs placebo. Bempedoic acid was associated with mild increases in blood urea nitrogen, creatinine, and uric acid and decreases in hemoglobin. These laboratory abnormalities were apparent by week 4, stable over time, and reversible after treatment cessation. Gout incidence was 1.6/100 vs 0.5/100 PY in the bempedoic acid vs placebo groups. New-onset diabetes/hyperglycemia occurred less frequently with bempedoic acid vs placebo (4.7/100 vs 6.4/100 PY). The safety profile was consistent across subgroups. Conclusions Bempedoic acid is generally safe and well tolerated among patients with hypercholesterolemia who require additional LLT

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

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

Lipoprotein(a): A Genetically Determined, Causal, and Prevalent Risk Factor for Atherosclerotic Cardiovascular Disease: A Scientific Statement From the American Heart Association

High levels of lipoprotein(a) [Lp(a)], an apoB100-containing lipoprotein, are an independent and causal risk factor for atherosclerotic cardiovascular diseases through mechanisms associated with increased atherogenesis, inflammation, and thrombosis. Lp(a) is predominantly a monogenic cardiovascular risk determinant, with ≈70% to ≥90% of interindividual heterogeneity in levels being genetically determined. The 2 major protein components of Lp(a) particles are apoB100 and apolipoprotein(a). Lp(a) remains a risk factor for cardiovascular disease development even in the setting of effective reduction of plasma low-density lipoprotein cholesterol and apoB100. Despite its demonstrated contribution to atherosclerotic cardiovascular disease burden, we presently lack standardization and harmonization of assays, universal guidelines for diagnosing and providing risk assessment, and targeted treatments to lower Lp(a). There is a clinical need to understand the genetic and biological basis for variation in Lp(a) levels and its relationship to disease in different ancestry groups. This scientific statement capitalizes on the expertise of a diverse basic science and clinical workgroup to highlight the history, biology, pathophysiology, and emerging clinical evidence in the Lp(a) field. Herein, we address key knowledge gaps and future directions required to mitigate the atherosclerotic cardiovascular disease risk attributable to elevated Lp(a) levels

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

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

Long-term mipomersen treatment is associated with a reduction in cardiovascular events in patients with familial hypercholesterolemia

Familial hypercholesterolemia (FH) is characterized by severely elevated LDL-cholesterol and up to a 20-fold increase in premature cardiovascular disease (CVD). Mipomersen has been shown to lower the levels of these atherogenic lipoproteins, but whether it lowers major adverse cardiac events (MACEs) has not been addressed. This post hoc analysis of prospectively collected data of three randomized trials and an open-label extension phase included patients that were exposed to ≥12 months of mipomersen. MACE rates that occurred during 24 months before randomization in the mipomersen group were compared to MACE rates after initiation of mipomersen. Data from the trials included in this report are registered in Clinicaltrials.gov (NCT00607373, NCT00706849, NCT00794664, NCT00694109). The occurrence of MACE events, defined as cardiovascular death, nonfatal acute myocardial infarction, hospitalization for unstable angina, coronary revascularization and nonfatal ischemic stroke, was obtained from medical history data pre-treatment and adjudicated by an independent adjudication committee for events occurring post-treatment with mipomersen. MACEs were identified in 61.5% of patients (64 patients with 146 events [39 myocardial infarctions, 99 coronary revascularizations, 5 unstable angina episodes, 3 ischemic strokes]) during 24 months before mipomersen treatment, and in 9.6% of patients (10 patients with 13 events [1 cardiovascular death, 2 myocardial infarctions, 6 coronary interventions, 4 unstable angina episodes]) during a mean of 24.4 months after initiation of mipomersen (MACE rate 25.7 of 1000 patient-months vs 3.9 of 1000 patient-months, OR = 0.053 [95% CI, 0.016-0.168], P < .0001 by the exact McNemar test). The reduction in MACE coincided with a mean absolute reduction in LDL-C of 70 mg/dL (-28%) and of non-HDL cholesterol of 74 mg/dL (-26%) as well as reduction in Lp(a) of 11 mg/dL (-17%). Long-term mipomersen treatment not only lowers levels of atherogenic lipoproteins but may also lead to a reduction in cardiovascular events in FH patient

Effect of fasting, refeeding, and dietary fat restriction on plasma leptin levels

The factors responsible for the variability in plasma leptin levels observed among individuals with similar body compositions remain unclear. To examine the impact of dietary variables, we compared the changes in leptin levels induced by fasting and dietary fat restriction with the expected decrease following a significant loss in adipose mass. A 21.4 +/- 3.7% weight loss led to a 76.3 +/- 8.1% decrease in mean plasma leptin level (25.2 +/- 9.3 to 6.1 +/- 3.4 ng/mL, P = 0.0001) in a group of 9 obese males. Despite a weight loss of only 2.6 +/- 0.8%, mean plasma leptin levels fell by 61.9 +/- 25.2% (8.5 +/- 4.5 to 2.4 +/- 0.5 ng/mL, P < 0.01) in 7 nonobese females subjected to 3 days of fasting. Leptin levels in fasted subjects returned to baseline within 12 h of refeeding. Individual high- and low-fat meals given to 19 subjects after an overnight fast had no effect on plasma leptin levels. Reduction in dietary fat content from 37-10% of total calories for 7 weeks was also without effect on plasma leptin levels in these subjects. We conclude that plasma leptin levels primarily reflect total adipose mass, rather than meal consumption or dietary energy source, but that the reduction in leptin levels with ongoing fasting is disproportionate to the reduction in adipose mass. The ability of fasting to deactivate this presumed physiological satiety system may have been advantageous in environments characterized by rapid changes in food availability