Inhibition of ASGR1 decreases lipid levels by promoting cholesterol excretion.

High cholesterol is a major risk factor for cardiovascular disease1. Currently, no drug lowers cholesterol through directly promoting cholesterol excretion. Human genetic studies have identified that the loss-of-function Asialoglycoprotein receptor 1 (ASGR1) variants associate with low cholesterol and a reduced risk of cardiovascular disease2. ASGR1 is exclusively expressed in liver and mediates internalization and lysosomal degradation of blood asialoglycoproteins3. The mechanism by which ASGR1 affects cholesterol metabolism is unknown. Here, we find that Asgr1 deficiency decreases lipid levels in serum and liver by stabilizing LXRα. LXRα upregulates ABCA1 and ABCG5/G8, which promotes cholesterol transport to high-density lipoprotein and excretion to bile and faeces4, respectively. ASGR1 deficiency blocks endocytosis and lysosomal degradation of glycoproteins, reduces amino-acid levels in lysosomes, and thereby inhibits mTORC1 and activates AMPK. On one hand, AMPK increases LXRα by decreasing its ubiquitin ligases BRCA1/BARD1. On the other hand, AMPK suppresses SREBP1 that controls lipogenesis. Anti-ASGR1 neutralizing antibody lowers lipid levels by increasing cholesterol excretion, and shows synergistic beneficial effects with atorvastatin or ezetimibe, two widely used hypocholesterolaemic drugs. In summary, this study demonstrates that targeting ASGR1 upregulates LXRα, ABCA1 and ABCG5/G8, inhibits SREBP1 and lipogenesis, and therefore promotes cholesterol excretion and decreases lipid levels.

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.).

Ezetimibe ameliorates cisplatin-induced nephrotoxicity: A novel therapeutic approach via modulating AMPK/Nrf2/TXNIP signaling.

Cisplatin (Cis) is among the most powerful antineoplastic medications, nevertheless, its serious side effects; particularly nephrotoxicity designates a major concern. Previous studies reported that ezetimibe (Eze), a well-known antihyperlipidemic drug, exerts additional trivial pharmacological effects. In this work, we displayed Eze as an intriguing protective candidate in a cisplatin-induced nephrotoxicity rat model through AMPK activation. Eze (10 mg/kg, p.o.) was administered for two weeks and Cis (10 mg/kg, i.p.) was administered on the 10th day to induce nephrotoxicity in male Wistar rats. Treatment with Eze greatly augmented the phosphorylation of adenosine 5'-monophosphate-activated protein kinase (AMPK) and the antioxidant regulator; nuclear factor erythroid 2-related factor 2 (Nrf2), thus, mitigating oxidative injury through induction of the antioxidant enzymes, such as heme oxygenase-1 (HO-1) and glutathione reductase (GR). As well, Eze relieved inflammation by reducing protein expression of thioredoxin-interacting protein (TXNIP) and nucleotide-binding domain-like receptor protein 3 (NLRP3), which led to a decrease in the release of caspase-1, in addition to, the inflammatory markers IL-18 and IL-1 ß. Besides, Eze ameliorated apoptosis in the renal cells through inhibiting the phosphorylated Apoptosis signal-regulating kinase-1(p-ASK1), caspase-3 and reducing Bax/Bcl2ratio. Correspondingly, histopathological examination corroborated the previous biochemical findings. Collectively, Eze exerts significant renal protection against Cis-induced nephrotoxicity via antioxidant, anti-inflammatory and anti-apoptotic pathways that are probably mediated, at least partly, via activating AMPK/Nrf2/HO-1 pathway and conquering both TXNIP/NLRP3 inflammasome and TXNIP/ASK1 signaling pathways. To confirm the protective effect of Eze via AMPK-activation, an AMPK-inhibitor, dorsomorphin (Dors), when co-administered with Eze abolished its protective effect.

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.

Repositioning of ezetimibe for the treatment of idiopathic pulmonary fibrosis.

BACKGROUND: We previously identified ezetimibe, an inhibitor of Niemann-Pick C1-like intracellular cholesterol transporter 1 and European Medicines Agency-approved lipid-lowering agent, as a potent autophagy activator. However, its efficacy against pulmonary fibrosis has not yet been evaluated. This study aimed to determine whether ezetimibe has therapeutic potential against idiopathic pulmonary fibrosis. METHODS: Primary lung fibroblasts isolated from both humans and mice were employed for mechanistic in vitro experiments. mRNA sequencing of human lung fibroblasts and gene set enrichment analysis were performed to explore the therapeutic mechanism of ezetimibe. A bleomycin-induced pulmonary fibrosis mouse model was used to examine in vivo efficacy of the drug. Tandem fluorescent-tagged microtubule-associated protein 1 light chain 3 transgenic mice were used to measure autophagic flux. Finally, the medical records of patients with idiopathic pulmonary fibrosis from three different hospitals were reviewed retrospectively, and analyses on survival and lung function were conducted to determine the benefits of ezetimibe. RESULTS: Ezetimibe inhibited myofibroblast differentiation by restoring the mechanistic target of rapamycin complex 1-autophagy axis with fine control of intracellular cholesterol distribution. Serum response factor, a potential autophagic substrate, was identified as a primary downstream effector in this process. Similarly, ezetimibe ameliorated bleomycin-induced pulmonary fibrosis in mice by inhibiting mechanistic target of rapamycin complex 1 activity and increasing autophagic flux, as observed in mouse lung samples. Patients with idiopathic pulmonary fibrosis who regularly used ezetimibe showed decreased rates of all-cause mortality and lung function decline. CONCLUSION: Our study presents ezetimibe as a potential novel therapeutic for idiopathic pulmonary fibrosis.

New insights into the therapeutic options to lower lipoprotein(a).

BACKGROUND: Elevated levels of lipoprotein(a) [Lp(a)] represent a risk factor for cardiovascular disease including aortic valve stenosis, myocardial infarction and stroke. While the patho-physiological mechanisms linking Lp(a) with atherosclerosis are not fully understood, from genetic studies that lower Lp(a) levels protect from CVD independently of other risk factors including lipids and lipoproteins. Hereby, Lp(a) has been considered an appealing pharmacological target. RESULTS: However, approved lipid lowering therapies such as statins, ezetimibe or PCSK9 inhibitors have a neutral to modest effect on Lp(a) levels, thus prompting the development of new strategies selectively targeting Lp(a). These include antisense oligonucleotides and small interfering RNAs (siRNAs) directed towards apolipoprotein(a) [Apo(a)], which are in advanced phase of clinical development. More recently, additional approaches including inhibitors of Apo(a) and gene editing approaches via CRISPR-Cas9 technology entered early clinical development. CONCLUSION: If the results from the cardiovascular outcome trials, designed to demonstrate whether the reduction of Lp(a) of more than 80% as observed with pelacarsen, olpasiran or lepodisiran translates into the decrease of cardiovascular mortality and major adverse cardiovascular events, will be positive, lowering Lp(a) will become a new additional target in the management of patients with elevated cardiovascular risk.

PSCK9 inhibitors reduced early recurrent stroke in patients with symptomatic intracranial atherosclerotic stenosis.

BACKGROUND: Symptomatic intracranial atherosclerotic stenosis (ICAS) is prone to cause early recurrent stroke (ERS). Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors lower low-density lipoprotein cholesterol (LDL-C) levels and prevent cardiovascular events. This multicentre, hospital-based prospective cohort study was designed to investigate whether PCSK9 inhibitors would prevent ERS in patients with symptomatic ICAS. METHODS: From 1 October 2020 to 30 September 2022, consecutive patients with acute ischaemic stroke attributed to ICAS admitted within 1 week after onset were enrolled and followed up for 1 month. Patients were divided into two groups, the PCSK9 inhibitors group receiving PCSK9 inhibitors add-on therapy, and the control group receiving statins and/or ezetimibe. The primary outcome was ERS. Cox proportional hazard models and Kaplan-Meier survival curve were used to estimate the association between PCSK9 inhibitors and ERS. RESULTS: At the end of follow-up, the LDL-C levels were further lowered by PCSK9 inhibitors add-on therapy (n=232, from 3.06±1.16 mmol/L to 2.12±1.19 mmol/L) than statins and/or ezetimibe treatment (n=429, from 2.91±1.05 mmol/L to 2.64±0.86 mmol/L, p<0.001). The Kaplan-Meier survival curves showed that PCSK9 inhibitors add-on therapy significantly reduced ERS (5.59%, 24/429, vs 2.16%, 5/232; log-rank test, p=0.044). The multivariate Cox regression analysis revealed that, after adjusting for confounders with a p value less than 0.05 in univariate analysis or of particular importance, the HR was 0.335 (95% CI 0.114 to 0.986, p=0.047), compared with the control group. CONCLUSIONS: In our study, PCSK9 inhibitors add-on therapy further reduced LDL-C levels and ERS in patients with symptomatic ICAS.

Association of lipid-lowering drug targets with risk of cutaneous melanoma: a mendelian randomization study.

BACKGROUND: Melanoma proliferation is partly attributed to dysregulated lipid metabolism. The effectiveness of lipid-lowering drugs in combating cutaneous melanoma (CM) is a subject of ongoing debate in both in vitro and clinical studies. METHOD: This study aims to evaluate the causal relationship between various lipid-lowering drug targets, namely 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR, targeted by statins), Proprotein convertase subtilisin/kexin type 9 (PCSK9, targeted by alirocumab and evolocumab), and Niemann-Pick C1-like 1 (NPC1L1, targeted by ezetimibe), and the outcomes of cutaneous melanoma. To mimic the effects of lipid-lowering drugs, we utilized two genetic tools: analysis of polymorphisms affecting the expression levels of drug target genes, and genetic variations linked to low-density lipoprotein cholesterol levels and drug target genes. These variations were sourced from genome-wide association studies (GWAS). We applied Summary-data-based Mendelian Randomization (SMR) and Inverse Variance Weighted Mendelian Randomization (IVW-MR) to gauge the effectiveness of these drugs. RESULTS: Our findings, with SMR results showing an odds ratio (OR) of 1.44 (95% CI: 1.08-1.92; P = 0.011) and IVW-MR results indicating an OR of 1.56 (95% CI: 1.10-2.23; P = 0.013), demonstrate a positive correlation between PCSK9 expression and increased risk of CM. However, no such correlations were observed in other analyses. CONCLUSION: The study concludes that PCSK9 plays a significant role in the development of CM, and its inhibition is linked to a reduced risk of the disease.

Obicetrapib: Reversing the Tide of CETP Inhibitor Disappointments.

PURPOSE OF REVIEW: To discuss the history of cardiovascular outcomes trials of cholesteryl ester transfer protein (CETP) inhibitors and to describe obicetrapib, a next-generation, oral, once-daily, low-dose CETP inhibitor in late-stage development for dyslipidemia and atherosclerotic cardiovascular disease (ASCVD). RECENT FINDINGS: Phase 1 and 2 trials have evaluated the safety and lipid/lipoprotein effects of obicetrapib as monotherapy, in conjunction with statins, on top of high-intensity statins (HIS), and with ezetimibe on top of HIS. In ROSE2, 10 mg obicetrapib monotherapy and combined with 10 mg ezetimibe, each on top of HIS, significantly reduced low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (non-HDL-C), apolipoprotein B, total LDL particles, small LDL particles, small, dense LDL-C, and lipoprotein (a), and increased HDL-C. Phase 3 pivotal registration trials including a cardiovascular outcomes trial are underway. Obicetrapib has an excellent safety and tolerability profile and robustly lowers atherogenic lipoproteins and raises HDL-C. As such, obicetrapib may be a promising agent for the treatment of ASCVD.

Moderate-intensity statin with ezetimibe combination therapy versus high-intensity statin monotherapy in patients with metabolic syndrome and atherosclerotic cardiovascular disease: A post-hoc analysis of the RACING trial.

AIM: This study evaluated the safety and efficacy of a moderate-intensity statin with ezetimibe combination therapy versus high-intensity statin monotherapy in patients with metabolic syndrome (MetS) and atherosclerotic cardiovascular disease. MATERIALS AND METHODS: In this post-hoc subgroup analysis of the RACING trial, patients were analysed based on the presence of MetS. MetS was defined as meeting at least three of the five following criteria: (a) elevated waist circumference; (b) elevated triglycerides; (c) reduced high-density lipoprotein cholesterol; (d) elevated blood pressure; and (e) elevated fasting glucose. The primary outcome was a 3-year composite of cardiovascular death, major cardiovascular events, or non-fatal stroke. RESULTS: Of the 3780 patients enrolled in the RACING trial, 1703 (45.1%) had MetS at baseline. The primary outcome rate was 10.1% and 10.3% in patients with MetS receiving ezetimibe combination therapy versus high-intensity statin monotherapy (hazard ratio = 0.97; 95% confidence interval = 0.72-1.32; p = .868). Lower rates of intolerance-related drug discontinuation or dose reduction (3.9% vs. 8.0%; p < .001) and lower low-density lipoprotein cholesterol levels (57 vs. 65 mg/dl; p < .001) were observed with ezetimibe combination therapy versus high-intensity statin monotherapy. Furthermore, the rate of new-onset diabetes was 18.5% and 19.1% in each group (p = .822). There were no significant interactions between MetS and therapy regarding study outcomes in the total population. CONCLUSIONS: In patients with MetS and atherosclerotic cardiovascular disease, a moderate-intensity statin with ezetimibe combination therapy had comparable cardiovascular benefits with those of high-intensity statin monotherapy. Meanwhile, ezetimibe combination therapy was associated with lower drug intolerance and low-density lipoprotein cholesterol levels, but there was no apparent between-group difference in new-onset diabetes.

Importance of Considering Fed-State Gastrointestinal Physiology in Predicting the Reabsorption of Enterohepatic Circulation of Drugs.

PURPOSE: The purpose of this study was to develop a simulation model for the pharmacokinetics (PK) of drugs undergoing enterohepatic circulation (EHC) with consideration to the environment in the gastrointestinal tract in the fed state in humans. The investigation particularly focused on the necessity of compensating for the permeability rate constant in the reabsorption process in consideration of drug entrapment in bile micelles. METHODS: Meloxicam and ezetimibe were used as model drugs. The extent of the entrapment of drugs inside bile micelles was evaluated using the solubility ratio of Fed State Simulated Intestinal Fluid version 2 (FeSSIF-V2) to Fasted State Simulated Intestinal Fluid version 2 (FaSSIF-V2). Prediction accuracy was evaluated using the Mean Absolute Percentage Error (MAPE) value, calculated from the observed and predicted oral PK profiles. RESULTS: The solubilization of ezetimibe by bile micelles was clearly observed while that of meloxicam was not. Assuming that only drugs in the free fraction of micelles permeate through the intestinal membrane, PK simulation for ezetimibe was performed in both scenarios with and without compensation by the permeation rate constant. The MAPE value of Zetia® tablet, containing ezetimibe, was lower with compensation than without compensation. By contrast, Mobic® tablet, containing meloxicam, showed a relatively low MAPE value even without compensation. CONCLUSION: For drugs which undergo EHC and can be solubilized by bile micelles, compensating for the permeation rate constant in the reabsorption process based on the free fraction ratio appears an important factor in increasing the accuracy of PK profile prediction.

Aggressive LDL-C Lowering and the Brain: Impact on Risk for Dementia and Hemorrhagic Stroke: A Scientific Statement From the American Heart Association.

The objective of this scientific statement is to evaluate contemporary evidence that either supports or refutes the conclusion that aggressive low-density lipoprotein cholesterol lowering or lipid lowering exerts toxic effects on the brain, leading to cognitive impairment or dementia or hemorrhagic stroke. The writing group used literature reviews, references to published clinical and epidemiology studies, clinical and public health guidelines, authoritative statements, and expert opinion to summarize existing evidence and to identify gaps in current knowledge. Although some retrospective, case control, and prospective longitudinal studies suggest that statins and low-density lipoprotein cholesterol lowering are associated with cognitive impairment or dementia, the preponderance of observational studies and data from randomized trials do not support this conclusion. The risk of a hemorrhagic stroke associated with statin therapy in patients without a history of cerebrovascular disease is nonsignificant, and achieving very low levels of low-density lipoprotein cholesterol does not increase that risk. Data reflecting the risk of hemorrhagic stroke with lipid-lowering treatment among patients with a history of hemorrhagic stroke are not robust and require additional focused study.

Metformin-Induced Proprotein Convertase Subtilisin/Kexin Type 9 Inhibition Further Decreases Low-Density Lipoprotein Cholesterol Following Statin Treatment in Patients With Coronary Artery Disease and Without Diabetes.

ABSTRACT: In vitro investigations have established metformin's capacity to downregulate proprotein convertase subtilisin/kexin type 9 (PCSK9) expression, suggesting a potential beneficial effect on atherogenic lipoprotein particles when combined with metformin therapy. Our objective was to assess whether metformin could mitigate statin-induced adverse effects on PCSK9, thereby improving lipid profiles in patients with coronary artery disease (CAD) but without diabetes. Employing an open-label, placebo-controlled, randomized trial, we randomized patients with CAD but without diabetes into CLA (cholesterol-lowering agents alone: atorvastatin ± ezetimibe, n = 38) and Met + CLA groups (metformin plus CLA, n = 33) in a 1:1 ratio. The primary end point was the therapeutic impact of 1-month metformin combination treatment on low-density lipoprotein cholesterol (LDL-C) and PCSK9 levels. Baseline LDL-C and PCSK9 levels were 76.18 mg·dL -1 and 80.54 ng·mL -1 , respectively. After 1 month, metformin significantly reduced LDL-C (-20.81%, P < 0.001), enabling 72% of patients to attain guideline-recommended LDL-C goals. Noteworthy reductions in PCSK9 levels (-15.03%, P < 0.001) were observed. Moreover, Met + CLA markedly reduced LDL particle number more than CLA alone (-10.65% vs. 1.45%, P = 0.009), primarily due to diminished small-dense LDL particle count. Mechanistically, our study demonstrated metformin's inhibition of statin-induced PCSK9 expression in human hepatocellular cells. In summary, a 1-month metformin combination regimen reduced LDL-C levels in patients with CAD but without diabetes by inhibiting PCSK9 expression. TRIAL REGISTRATION: Chinese Clinical Trial Registry identifier: ChiCTR1900026925 (26/10/2019).

Bempedoic Acid: How Will It Shape the Future Lipid-Lowering Landscape? Mode of Action, Evidence, and Clinical Use.

BACKGROUND: Low-density lipoproteins are now proven to be causal for atherosclerosis. Pharmacological treatment focuses on an increase of low-density lipoprotein (LDL) receptors, particularly in the hepatocyte, which leads to uptake of LDL from blood, thereby reducing the burden to the arterial wall. This mechanism has first been proven by statins to be effective to reduce cardiovascular morbidity and mortality. The concept of "the lower, the better" was shown by high-intensity statins and new compounds like ezetimibe, PCSK9 antibodies, inclisiran, and ultimately bempedoic acid. SUMMARY: Although first considered only a relatively weak LDL-C lowering drug, bempedoic acid proved to be very effective, for example, in statin-intolerant patients to reduce cardiovascular events in the CLEAR-Outcomes study. In the era of personalized medicine, it should not be forgotten that the individual response to a LDL-C lowering drug can vary considerably. Bempedoic acid has a favorable safety profile, particularly it does not induce muscle problems because its precursor is not metabolized to the active drug in the muscle, and it does not induce hyperglycemia. Bempedoic acid probably is best used in combination with ezetimibe, which leads to LDL-C reductions in the range of moderately intensive statins; in an oral triple combination with a high-intensity statin, LDL-C reductions in the range of two-thirds can be achieved. KEY MESSAGES: Bempedoic acid is a further weapon against the atherogenic effect of LDL cholesterol - in both primary and secondary prevention.

Optimizing Post-Acute Coronary Syndrome Dyslipidemia Management: Insights from the North American Acute Coronary Syndrome Reflective III.

INTRODUCTION: Despite contemporary practice guidelines, a substantial number of post-acute coronary syndrome (ACS) patients fail to achieve guideline-recommended LDL-C thresholds. Our study aimed to investigate this guideline recommendations-to-practice care gap. Specifically, we aimed to identify opportunities where additional lipid-lowering therapies are indicated and explore reasons for the non-prescription of guideline-recommended therapies. METHODS: ACS patients with LDL-C ≥1.81 mmol/L (70 mg/dL) despite maximally tolerated statin ± ezetimibe therapy (including those intolerant of ≥2 statins) were enrolled 1-12 months post-event from 27 Canadian and US sites from September 2018 to October 2020 and followed up for three visits during the 12 months post-event. We determined the proportion of patients who did not achieve Canadian/US guideline-recommended LDL-C thresholds, the number of patients who would have been eligible for additional lipid-lowering therapies, and reasons behind lack of escalation in lipid-lowering therapies when indicated. Individual patient and aggregate practice feedback, including guideline-recommended intensification suggestions, were provided to each physician. RESULTS: Of the 248 patients enrolled in the pilot study (median age 64 [57, 73] years, 31.5% female and STEMI 27.4%), 75.4% were on high-intensity statins on the first visit. A total of 18.5% of those who attended all 3 visits had an LDL-C measured only at the first visit which was above the threshold. After 1 year of follow-up, 51.9% of patients achieved LDL-C thresholds at either visit 2 or 3. In the context of feedback reminding physicians about guideline-directed LDL-C-modifying therapy in their individual participating patients, we observed an increase in the use of ezetimibe and PCSK9 inhibitor therapy at 3-12 months. This was associated with a significant lowering of the mean LDL-C (from 2.93 mmol/L [baseline] to 2.09 mmol/L [3-6 months] to 1.87 mmol/L [6-12 months]) and a significantly greater proportion of patients (from 0% [baseline] to 38.6% [3-6 months] to 53.4% [6-12 months]) achieving guideline-recommended LDL-C thresholds. The most prevalent reasons behind the non-intensification of LDL-C-lowering therapy with ezetimibe and/or PCSK9i were LDL-C levels being close to target, the pre-existing use of other lipid-lowering therapies, patient refusal, and cost. CONCLUSION: Although most patients post-ACS were on high-intensity statin therapy, almost 50% failed to achieve guideline-recommended LDL-C thresholds by 1-year follow-up. Furthermore, additional lipid-lowering therapies in this high-risk group were underprescribed, and this might be linked to several factors including potential gaps in physician knowledge, treatment inertia, patient refusal, and cost.

Ezetimibe ketone protects against renal ischemia-reperfusion injury and attenuates oxidative stress via activation of the Nrf2/HO-1 signaling pathway.

Recently, ezetimibe (EZM) has been suggested to be a potent Nrf2 activator that is important for preventing oxidative stress. Interestingly, we found that its metabolite ezetimibe ketone (EZM-K) also has antioxidant effects. Thus, we investigated the role of EZM-K in preventing renal ischemia‒reperfusion injury (RIRI). Cultured NRK-52E cells were subjected to simulated IR with or without EZM-K. Rats were used to simulate in vivo experiments. EZM-K alleviated H2O2-induced apoptosis and reactive oxygen species (ROS) and upregulated Nrf2 and HO-1 levels in NRK-52E cells. A HO-1 and a Nrf2 inhibitor reversed the protective effects of EZM-K. In the rat RIRI model, pretreatment with EZM-K activated the Nrf2/HO-1 signaling pathway, suppressed tubular injury and inflammation, and improved renal function. EZM-K significantly prevented renal injury caused by ischemia‒reperfusion via the Nrf2/HO-1 signaling axis both in vivo and in vitro. The other metabolite of EZM, ezetimibe glucuronide (EZM-G) had no protective effects against ROS in RIRI. EZM-G also had no antioxidant effects and could not activate Nrf2/HO-1 signal pathway. Our findings also indicated the therapeutic potential of EZM-K in preventing RIRI.

Degree of serum LDL cholesterol reduction by simvastatin and ezetimibe is dependent on baseline LDL cholesterol concentration but not on baseline values and changes in cholesterol synthesis and absorption parameters.

OBJECTIVE: We questioned whether the baseline status of low-density lipoprotein cholesterol (LDL-C), cholesterol synthesis and absorption, and the changes in these parameters determine the change in serum LDL-C under statin or ezetimibe treatment or under combination treatment. MATERIALS AND METHODS: 37 mildly hypercholesterolemic healthy male subjects were studied under placebo, simvastatin (20 mg/d), ezetimibe (10 mg/d), and combination treatment. We correlated the change of LDL-C (ΔLDL-C) under treatment with the placebo end values of LDL-C (baseline), whole-body cholesterol synthesis, and hepatic cholesterol synthesis (serum lathosterol to cholesterol ratio) as well as fractional absorption rate (FAR) of cholesterol and serum campesterol to cholesterol ratio. The change in serum LDL-C was also correlated with the changes in synthesis and absorption parameters. RESULTS: ΔLDL-C was highly negatively related to baseline LDL-C under ezetimibe (p < 0.0001), simvastatin (p < 0.0001), and combination treatment (p < 0.0001). Under combination treatment, LDL-C lowering appears possible from baseline values of 10 mg/dL upwards, while ΔLDL-C was independent of the baseline value (-50 to -60%). ΔLDL-C was positively associated with placebo FAR under ezetimibe (p = 0.0106) and combination treatment (p = 0.0457). No associations were found between ΔLDL-C and baseline values for synthesis nor between ΔLDL-C and changes in synthesis and absorption surrogate markers. CONCLUSION: Under ezetimibe, simvastatin, and combination treatment, ΔLDL-C is predominantly dependent on the baseline LDL-C concentration. We hypothesize that the concentration gradient between serum LDL-C and hepatic cellular cholesterol determines the efficiency of serum LDL-C lowering. Combination treatment is the preferred treatment.

Gene variants and clinical characteristics of children with sitosterolemia.

OBJECTIVE: To enhance the detection, management and monitoring of Chinese children afflicted with sitosterolemia by examining the physical characteristics and genetic makeup of pediatric patients. METHODS: In this group, 26 children were diagnosed with sitosterolemia, 24 of whom underwent genetic analysis. Patient family medical history, physical symptoms, tests for liver function, lipid levels, standard blood tests, phytosterol levels, cardiac/carotid artery ultrasounds, fundus examinations, and treatment were collected. RESULTS: The majority (19, 73.1%) of the 26 patients exhibited xanthomas as the most prevalent manifestation. The second most common symptoms were joint pain (7, 26.9%) and stunted growth (4, 15.4%). Among the 24 (92.3%) patients whose genetics were analyzed, 16 (66.7%) harbored ABCG5 variants (type 2 sitosterolemia), and nearly one-third (8, 33.3%) harbored ABCG8 variants (type 1 sitosterolemia). Additionally, the most common pathogenic ABCG5 variant was c.1166G > A (p.Arg389His), which was found in 10 patients (66.7%). Further analysis did not indicate any significant differences in pathological traits among those carrying ABCG5 and ABCG8 variations (P > 0.05). Interestingly, there was a greater abundance of nonsense variations in ABCG5 than in ABCG8 (P = 0.09), and a greater frequency of splicing variations in ABCG8 than ABCG5 (P = 0.01). Following a change in diet or a combination of ezetimibe, the levels of cholesterol and low-density lipoprotein were markedly decreased compared to the levels reported before treatment. CONCLUSION: Sitosterolemia should be considered for individuals presenting with xanthomas and increased cholesterol levels. Phytosterol testing and genetic analysis are important for early detection. Managing one's diet and taking ezetimibe can well control blood lipids.

Australian and New Zealand Living Guideline cholesterol-lowering therapy for people with chronic kidney disease (CARI Guidelines): Reducing the evidence-practice gap.

AIM: People with chronic kidney disease experience high rates of cardiovascular disease. Cholesterol-lowering therapy is a mainstay in the management but there is uncertainty in the treatment effects on patient-important outcomes, such as fatigue and rhabdomyolysis. Here, we summarise the updated CARI Australian and New Zealand Living Guidelines on cholesterol-lowering therapy in chronic kidney disease. METHODS: We updated a Cochrane review and monitored newly published studies weekly to inform guideline development according to international standards. The Working Group included expertise from nephrology, cardiology, Indigenous Health, guideline development and people with lived experience of chronic kidney disease. RESULTS: The guideline recommends people with chronic kidney disease (eGFR ≥15 mL/min/1.73 m2) and an absolute cardiovascular risk of 10% or higher should receive statin therapy (with or without ezetimibe) to reduce the risk of cardiovascular events and death (strong recommendation, moderate certainty evidence). The guidelines also recommends a lower absolute cardiovascular risk threshold (≥5%) for Aboriginal and Torres Strait Islander Peoples and Maori with chronic kidney disease to receive statin therapy (with or without ezetimibe) (strong recommendation, low certainty evidence). The evidence was actively surveyed from 2020-2023 and updated as required. No changes to guideline recommendations were made, with no new data on the balance and benefits of harms. CONCLUSIONS: The development of living guidelines was feasible and provided the opportunity to update recommendations to improve clinical decision-making in real-time. Living guidelines provide the opportunity to transform chronic kidney disease guidelines.

Analytical method development and validation for simultaneous estimation of Bempedoic acid and Ezetimibe in pure and its pharmaceutical dosage form by RP-HPLC.

A simple, accurate and precise method was developed for the simultaneous estimation of the bempedoic acid and ezetimibe in pure and tablet dosage form. The developed method was validated as per International Conference on Harmonization guidelines. The chromatographic separation was achieved isocratically on a Waters- C18, 250 × 4.6 mm, 5 µm column. Mobile phase containing K2HPO4-methanol in the ratio 60:40 in buffer at pH 4.3 was pumped through column at a flow rate of 1.0 ml/min. The temperature was maintained at 25°C. The optimized wavelength selected was 242 nm. The separation of bempedoic acid and ezetimibe showed retention times of 3.090 and 4.268 min respectively. The RSD values of the bempedoic acid and ezetimibe were 0.34 and 0.08 respectively. The accuracy of method was determined at three levels (50,100 and 150%). The percentage recovery was obtained as 100.0 and 100.0% for bempedoic acid and ezetimibe, respectively. The limits of determination and quantitation obtained from regression equations of bempedoic acid and ezetimibe were 1.065, 3.550 and 0.203, 0.677, respectively. The regression equation of bempedoic acid is y = 20,795x + 24,168, and it is y = 6,885.7x + 11,000 for ezetimibe. The retention times were decreased and the run time was decreased, so that the method developed is simple and economical that can be adopted for regular quality control tests in industry.