LDL-cholesterol reduction in patients with hypercholesterolemia by modulation of adenosine triphosphate-citrate lyase and adenosine monophosphate-activated protein kinase

Safety and efficacy of bempedoic acid: a systematic review and meta-analysis of randomised controlled trials

BACKGROUND AND AIMS

Bempedoic Acid (BA) is a novel Lipid-Lowering Therapy (LLT). We performed a systematic review and meta-analysis to assess the efficacy and safety of BA in patients with hypercholesterolemia.

METHODS

PubMed, Scopus, and Cochrane library databases were searched for randomised controlled trials evaluating the efficacy and/or safety of BA compared with placebo. Trials investigating dosages other than 180 mg/die were excluded. Major adverse cardiovascular events (MACE) were the primary efficacy endpoint. LDL-cholesterol reduction was the primary laboratory endpoint. Pre-specified safety endpoints included muscle-related adverse events, new-onset diabetes, and gout. The protocol was registered on PROSPERO (temporary ID:399,867).

RESULTS

Study search identified 275 deduplicated results. 11 studies, encompassing 18,315 patients (9854 on BA vs 8461 on placebo/no treatment) were included. BA was associated with a reduced risk of MACE (OR 0.86, 95% CI 0.79-0.95), myocardial infarction (OR 0.76, 95% CI 0.64-0.88) and unstable angina (OR 0.69, 95% CI 0.54-0.88) compared to control, over a median follow up of 87 (15-162) weeks. BA was associated with a reduction of LDL-Cholesterol (mean difference [MD]-22.42,95% CI - 24.02% to - 20.82%), total cholesterol (- 16.50%,95% - 19.21% to - 13.79%), Apo-B lipoprotein (- 19.55%, - 22.68% to - 16.42%) and high-sensitivity CRP (- 27.83%, - 31.71% to - 23.96%) at 12 weeks. BA was associated with a higher risk of gout (OR 1.55, 95% CI 1.27-1.90) as compared with placebo. Efficacy on laboratory endpoints was confirmed, with a variable extent, across patients on statin or ezetimibe background therapy.

CONCLUSIONS

The improved cholesterol control achieved with BA translates into a reduced risk of MACE, including myocardial infarction and coronary revascularisation. The drug has a satisfactory safety profile except for an increased risk of gout.

Bempedoic Acid can Reduce Cardiovascular Events in Combination with Statins or As Monotherapy: A Systematic Review and Meta-analysis

AIM

Bempedoic acid has shown noteworthy progress in the prevention and management of atherosclerotic cardiovascular disease (ASCVD) in recent years. However, there has been a lack of high-quality evidence regarding the risk reduction of clinical events with bempedoic acid. Therefore, the aim of this article is to conduct a comprehensive evaluation of the impact of bempedoic acid on the incidence of cardiovascular events.

METHODS

A systematic review and meta-analysis of randomized controlled trials pertaining to bempedoic acid was carried out. We conducted a systematic search across the Pubmed, Embase, and Cochrane Central Register of Controlled Trials databases to identify relevant studies published from inception to 23 April 2023. A total of four trials comparing the clinical benefit achieved with bempedoic acid versus placebo were included.

RESULTS

Our analysis comprised four trials that encompassed a total of 17,323 patients. In comparison to the placebo, bempedoic acid showed a significant reduction in the risk of major adverse cardiovascular events (MACE) [relative risk (RR), 0.86, 95% confidence interval (CI) 0.87-0.94]. Additionally, bempedoic acid substantially lowered the occurrence of fatal or nonfatal myocardial infarction (RR 0.76, 95% CI 0.66-0.89), hospitalization for unstable angina (RR 0.70, 95% CI 0.55-0.89), and coronary revascularization (RR 0.82, 95% CI 0.73-0.92). There was also a similar reduction in MACE in patients on the maximally tolerated statin therapy.

CONCLUSION

Bempedoic acid may reduce the risk of cardiovascular events regardless of whether the patient is taking stains or not.

REGISTRATION

PROSPERO registration number CRD42023422932.

The lipogenic enzyme acetoacetyl-CoA synthetase and ketone body utilization for denovo lipid synthesis, a review

Acetoacetyl-CoA synthetase (AACS) is the key enzyme in the anabolic utilization of ketone bodies (KBs) for denovo lipid synthesis, a process that bypasses citrate and ATP citrate lyase. This review shows that AACS is a highly regulated, cytosolic, and lipogenic enzyme and that many tissues can readily use KBs for denovo lipid synthesis. AACS has a low micromolar Km for acetoacetate, and supply of acetoacetate should not limit its activity in the fed state. In many tissues, AACS appears to be regulated in conjunction with the need for cholesterol, but in adipose tissue, it seems tied to fatty acid synthesis. KBs are readily utilized as substrates for lipid synthesis in lipogenic tissues, including liver, adipose tissue, lactating mammary gland, skin, intestinal mucosa, adrenals, and developing brain. In numerous studied cases, KBs served several-fold better than glucose as substrates for lipid synthesis, and when present, KBs suppressed the utilization of glucose for lipid synthesis. Here, it is hypothesized that a physiological role for the utilization of KBs for lipid synthesis is a metabolic process of lipid interconversion. Fatty acids are converted to KBs in liver, and then, the KBs are utilized to synthesize cholesterol and other long-chain fatty acids in liver and nonhepatic tissues. The conversion of fatty acids to cholesterol via the KBs may be a particularly important example of lipid interconversion. Utilizing KBs for lipid synthesis is glucose sparing and probably is important with low carbohydrate diets. Metabolic situations and tissues where this pathway may be important are discussed.

Tuftelin 1 Facilitates Hepatocellular Carcinoma Progression through Regulation of Lipogenesis and Focal Adhesion Maturation

Hepatocellular carcinoma (HCC) is the most common type of primary liver malignancy with poor prognosis worldwide. Emerging evidences demonstrated critical roles of lipid de novo synthesis in HCC progression, yet its regulatory mechanisms are not fully understood. Herein, we found that tuftelin 1 (TUFT1), an acidic phosphorylated glycoprotein with secretory capacity, was significantly upregulated in HCC and had an excellent correlation with patient survival and malignancy features. Through database mining and experimental validation, we found that TUFT1 was associated with fatty acid metabolism and promoted lipid accumulation in HCC cells. Further, we found that TUFT1 can interact with CREB1, a transcription factor for hepatic lipid metabolism, and regulate its activity and the transcriptions of key enzymes for lipogenesis. TUFT1 promoted HCC cell proliferation significantly, which was partially reversed by treatment of an inhibitor of CREB1, KG-501. Moreover, TUFT1 promoted the capacity of HCC cell invasion in vitro, which was likely mediated by its association with zyxin, a zinc-binding phosphoprotein responsible for the formation of fully mature focal adhesions on extracellular matrix. We found that TUFT1 can interact with ZYX and inhibit its expression and recruitments to focal complexes in HCC cells. Collectively, our study uncovered new regulatory mechanisms of TUFT1-mediated lipogenesis, cell proliferation, and invasion.

Discovery of a Novel Macrocyclic ATP Citrate Lyase Inhibitor

ATP citrate lyase (ACLY) is an important metabolic enzyme involved in the synthesis of fatty acid and cholesterol. The inhibition of ACLY is considered as a promising therapeutic strategy for various metabolic diseases and numerous malignancies. In this study, a novel macrocyclic compound 2 has been identified as a potent ACLY inhibitor with the "ring closing" strategy for conformational restriction based on NDI-091143. It showed potent ACLY inhibitory activity and binding affinity comparable to the positive control. Furthermore, compared with the positive control (T_1/2 = 3.36 min), the metabolic stability of 2 in HLMs (T_1/2 = 531.22 min) was significantly improved. All of these results characterized 2 as a promising lead compound worthy of further study.

ONECUT2 facilitates hepatocellular carcinoma metastasis by transcriptionally upregulating FGF2 and ACLY

Metastasis is the predominant reason for high mortality of hepatocellular carcinoma (HCC) patients. It is critical to explore the molecular mechanism underlying HCC metastasis. Here, we reported that transcription factor One Cut homeobox 2 (ONECUT2) functioned as an oncogene to facilitate HCC metastasis. Elevated ONECUT2 expression was positively correlated with increased tumor number, tumor encapsulation loss, microvascular invasion, poor tumor differentiation, and advanced TNM stage. Mechanistically, ONECUT2 directly bound to the promoters of fibroblast growth factor 2 (FGF2) and ATP citrate lyase (ACLY) and transcriptionally upregulated their expression. Knockdown of FGF2 and ACLY inhibited ONECUT2-mediated HCC metastasis, whereas upregulation of FGF2 and ACLY rescued ONECUT2 knockdown-induced suppression of HCC metastasis. ONECUT2 expression was positively correlated with FGF2 and ACLY expression in human HCC tissues. HCC patients with positive coexpression of ONECUT2/FGF2 or ONECUT2/ACLY exhibited the worst prognosis. In addition, FGF2 upregulated ONECUT2 expression through the FGFR1/ERK/ELK1 pathway, which formed an FGF2-FGFR1-ONECUT2 positive feedback loop. Knockdown of ONECUT2 inhibited FGF2-induced HCC metastasis. Furthermore, the combination of FGFR1 inhibitor PD173074 with ACLY inhibitor ETC-1002 markedly suppressed ONECUT2-mediated HCC metastasis. In summary, ONECUT2 was a potential prognostic biomarker in HCC and targeting this oncogenic signaling pathway may provide an efficient therapeutic strategy against HCC metastasis.

Metabolic reprogramming and epigenetic modifications on the path to cancer

Metabolic rewiring and epigenetic remodeling, which are closely linked and reciprocally regulate each other, are among the well-known cancer hallmarks. Recent evidence suggests that many metabolites serve as substrates or cofactors of chromatin-modifying enzymes as a consequence of the translocation or spatial regionalization of enzymes or metabolites. Various metabolic alterations and epigenetic modifications also reportedly drive immune escape or impede immunosurveillance within certain contexts, playing important roles in tumor progression. In this review, we focus on how metabolic reprogramming of tumor cells and immune cells reshapes epigenetic alterations, in particular the acetylation and methylation of histone proteins and DNA. We also discuss other eminent metabolic modifications such as, succinylation, hydroxybutyrylation, and lactylation, and update the current advances in metabolism- and epigenetic modification-based therapeutic prospects in cancer.

Targeting lipid metabolism is an emerging strategy to enhance the efficacy of anti-HER2 therapies in HER2-positive breast cancer

De novo or acquired resistance of cancer cells to currently available Human Epidermal Growth Factor Receptor 2 (HER2) inhibitors represents a clinical challenge. Several resistance mechanisms have been identified in recent years, with lipid metabolism reprogramming, a well-established hallmark of cancer, representing the last frontier of preclinical and clinical research in this field. Fatty Acid Synthase (FASN), the key enzyme required for fatty acids (FAs) biosynthesis, is frequently overexpressed/activated in HER2-positive (HER2+) breast cancer (BC), and it crucially sustains HER2+ BC cell growth, proliferation and survival. After the synthesis of new, selective and well tolerated FASN inhibitors, clinical trials have been initiated to test if these compounds are able to re-sensitize cancer cells with acquired resistance to HER2 inhibition. More recently, the upregulation of FA uptake by cancer cells has emerged as a potentially new and targetable mechanism of resistance to anti-HER2 therapies in HER2+ BC, thus opening a new era in the field of targeting metabolic reprogramming in clinical setting. Here, we review the available preclinical and clinical evidence supporting the inhibition of FA biosynthesis and uptake in combination with anti-HER2 therapies in patients with HER2+ BC, and we discuss ongoing clinical trials that are investigating these combination approaches.

The IKKβ-USP30-ACLY Axis Controls Lipogenesis and Tumorigenesis

BACKGROUND AND AIMS

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related death that develops as a consequence of obesity, cirrhosis, and chronic hepatitis. However, the pathways along which these changes occur remain incompletely understood.

APPROACH AND RESULTS

In this study, we show that the deubiquitinase USP30 is abundant in HCCs that arise in mice maintained on high-fat diets. IKKβ phosphorylated and stabilized USP30, which promoted USP30 to deubiquitinate ATP citrate lyase (ACLY) and fatty acid synthase (FASN). IKKβ also directly phosphorylated ACLY and facilitated the interaction between USP30 and ACLY and the latter's deubiquitination. In HCCs arising in DEN/CCl₄ -treated mice, USP30 deletion attenuated lipogenesis, inflammation, and tumorigenesis regardless of diet. The combination of ACLY inhibitor and programmed death ligand 1 antibody largely suppressed chemical-induced hepatocarcinogenesis. The IKKβ-USP30-ACLY axis was also found to be up-regulated in human HCCs.

CONCLUSIONS

This study identifies an IKKβ-USP30-ACLY axis that plays an essential and wide-spread role in tumor metabolism and may be a potential therapeutic target in HCC.

Novel therapeutic targets and agents for pediatric dyslipidemia

Landmark studies have convincingly demonstrated that atherosclerosis begins in youth. While generally asymptomatic, an increasing number of youth with disorders of lipid and lipoprotein metabolism, such as familial hypercholesterolemia, are being identified through selective and universal screening. While a heart healthy lifestyle is the foundation of treatment for all youth with dyslipidemia, lipid-lowering therapy may be required by some to prevent morbidity and premature mortality, especially when initiated at a young age. When appropriate, use of statins has become standard of care for reducing low-density lipoprotein cholesterol, while fibrates may be beneficial in helping to lower triglycerides. Many therapeutic options commonly used in adults are not yet approved for use in youth less than 18 years of age. Although currently available lipid-lowering therapy is well tolerated and safe when administered to youth, response to treatment may vary and some conditions lack an efficient therapeutic option. Thus, newer agents are needed to aid in management. Many are in development and clinical trials in youth are currently in progress but will require FDA approval before becoming commercially available. Many utilize novel approaches to favorably alter lipid and lipoprotein metabolism. In the absence of long-term outcome data of youth who were treated beginning at an early age, clinical registries may prove to be useful in monitoring safety and efficacy and help to inform clinical decision-making. In this manuscript, we review currently available and novel therapeutic agents in development for the treatment of elevated cholesterol and triglycerides.

Efficacy and safety of bempedoic acid for prevention of cardiovascular events and diabetes: a systematic review and meta-analysis

Background

Bempedoic acid is an oral, once-daily, first-in-class drug being developed for the treatment of hyperlipidemia. However, evidence of bempedoic acid use for the prevention of cardiovascular events and diabetes is lacking. Thus, we aim to evaluate the benefit and safety of bempedoic acid use for the prevention of cardiovascular events and diabetes.

Methods

We searched Medline, Embase, and the Cochrane Central Register of Controlled Trials with no language restriction from inception until March 3, 2020. Pairs of reviewers independently identified randomized controlled trials comparing the use of bempedoic acid with placebo or no treatment for primary prevention of cardiovascular events in statin-intolerant patients with hypercholesterolemia. The primary outcomes were major adverse cardiac events, and percent change in LDL-C.

Results

We identified 11 trials including a total of 4391 participants. Bempedoic acid use was associated with a reduction in composite cardiovascular outcome (RR 0.75, 95% CI 0.56–0.99; I² = 0%). Bempedoic acid reduced LDL-C levels (MD − 22.91, 95% CI − 27.35 to − 18.47; I² = 99%), and similarly reduced CRP levels (MD -24.70, 95% CI − 32.10 to − 17.30; I² = 53%). Bempedoic acid was associated with a reduction in rates of new-onset or worsening diabetes (RR 0.65, 95% CI 0.44–0.96; I² = 23%).

Conclusions

Bempedoic acid in patients with hypercholesterolemia was associated with a lower risk of cardiovascular events and diabetes.

Reprogramming of fatty acid metabolism in cancer

A common feature of cancer cells is their ability to rewire their metabolism to sustain the production of ATP and macromolecules needed for cell growth, division and survival. In particular, the importance of altered fatty acid metabolism in cancer has received renewed interest as, aside their principal role as structural components of the membrane matrix, they are important secondary messengers, and can also serve as fuel sources for energy production. In this review, we will examine the mechanisms through which cancer cells rewire their fatty acid metabolism with a focus on four main areas of research. (1) The role of de novo synthesis and exogenous uptake in the cellular pool of fatty acids. (2) The mechanisms through which molecular heterogeneity and oncogenic signal transduction pathways, such as PI3K-AKT-mTOR signalling, regulate fatty acid metabolism. (3) The role of fatty acids as essential mediators of cancer progression and metastasis, through remodelling of the tumour microenvironment. (4) Therapeutic strategies and considerations for successfully targeting fatty acid metabolism in cancer. Further research focusing on the complex interplay between oncogenic signalling and dysregulated fatty acid metabolism holds great promise to uncover novel metabolic vulnerabilities and improve the efficacy of targeted therapies.

Lipid-Lowering Agents

Several new or emerging drugs for dyslipidemia owe their existence, in part, to human genetic evidence, such as observations in families with rare genetic disorders or in Mendelian randomization studies. Much effort has been directed to agents that reduce LDL (low-density lipoprotein) cholesterol, triglyceride, and Lp[a] (lipoprotein[a]), with some sustained programs on agents to raise HDL (high-density lipoprotein) cholesterol. Lomitapide, mipomersen, AAV8.TBG.hLDLR, inclisiran, bempedoic acid, and gemcabene primarily target LDL cholesterol. Alipogene tiparvovec, pradigastat, and volanesorsen primarily target elevated triglycerides, whereas evinacumab and IONIS-ANGPTL3-L_Rx target both LDL cholesterol and triglyceride. IONIS-APO(a)-L_Rx targets Lp(a).

Aberrant lipid metabolism as a therapeutic target in liver cancer

INTRODUCTION

Hepatocellular carcinoma (HCC) is one of the most common and lethal cancers. Progress has been made in treatment of HCC; however, improved outcomes are much needed. The increased metabolic needs of cancer cells underscore the importance of metabolic pathways in cancer cell survival. Lipid metabolism has a role in HCC development; aberrant overexpression of several key enzymes is seen in many solid human tumors. Areas covered: We discuss aberrant lipid metabolism and the promise of multiple targets, in particular related to HCC treatment. We searched PubMed and clinicaltrials.gov for published and unpublished studies from 2000 to 2019. These terms were used: lipids, fatty acid metabolism, lipid metabolism, liver cancer, HCC, de novo fatty acid synthesis, ATP citrate lyase, stearoyl CoA denaturase, fatty acid synthase, acetyl coenzyme A carboxylase, CD147, KLF4, monoglyceride lipase, AMP activated protein kinase. Expert opinion: The importance of dysregulation of fatty acid synthesis in cancer is a growing area of research. HCC demonstrates significant alteration in lipid metabolism, representing great potential as a target for novel therapeutics. Various agents have demonstrated promising anti-neoplastic activity. This strategy deserves further development for improved outcomes.

Postprandial hyperglycemia and postprandial hypertriglyceridemia in type 2 diabetes

Postprandial glucose level is an independent risk factor for cardiovascular disease that exerts effects greater than glucose levels at fasting state, whereas increase in serum triglyceride level, under both fasting and postprandial conditions, contributes to the development of arteriosclerosis. Insulin resistance is a prevailing cause of abnormalities in postabsorptive excursion of blood glucose and postprandial lipid profile. Excess fat deposition renders a vicious cycle of hyperglycemia and hypertriglyceridemia in the postprandial state, and both of which are contributors to atherosclerotic change of vessels especially in patients with type 2 diabetes mellitus. Several therapeutic approaches for ameliorating each of these abnormalities have been attempted, including various antidiabetic agents or new compounds targeting lipid metabolism.

Prevention of Diet-Induced Metabolic Dysregulation, Inflammation, and Atherosclerosis in Ldlr −/− Mice by Treatment With the ATP-Citrate Lyase Inhibitor Bempedoic Acid

Objective—

Bempedoic acid (ETC-1002, 8-hydroxy-2,2,14,14-tetramethylpentadecanedioic acid) is a novel low-density lipoprotein cholesterol–lowering compound. In animals, bempedoic acid targets the liver where it inhibits cholesterol and fatty acid synthesis through inhibition of ATP-citrate lyase and through activation of AMP-activated protein kinase. In this study, we tested the hypothesis that bempedoic acid would prevent diet-induced metabolic dysregulation, inflammation, and atherosclerosis.

Approach and Results—

Ldlr −/− mice were fed a high-fat, high-cholesterol diet (42% kcal fat, 0.2% cholesterol) supplemented with bempedoic acid at 0, 3, 10 and 30 mg/kg body weight/day. Treatment for 12 weeks dose-dependently attenuated diet-induced hypercholesterolemia, hypertriglyceridemia, hyperglycemia, hyperinsulinemia, fatty liver and obesity. Compared to high-fat, high-cholesterol alone, the addition of bempedoic acid decreased plasma triglyceride (up to 64%) and cholesterol (up to 50%) concentrations, and improved glucose tolerance. Adiposity was significantly reduced with treatment. In liver, bempedoic acid prevented cholesterol and triglyceride accumulation, which was associated with increased fatty acid oxidation and reduced fatty acid synthesis. Hepatic gene expression analysis revealed that treatment significantly increased expression of genes involved in fatty acid oxidation while suppressing inflammatory gene expression. In full-length aorta, bempedoic acid markedly suppressed cholesteryl ester accumulation, attenuated the expression of proinflammatory M1 genes and attenuated the iNos / Arg1 ratio. Treatment robustly attenuated atherosclerotic lesion development in the aortic sinus by 44%, with beneficial changes in morphology, characteristic of earlier-stage lesions.

Conclusions—

Bempedoic acid effectively prevents plasma and tissue lipid elevations and attenuates the onset of inflammation, leading to the prevention of atherosclerotic lesion development in a mouse model of metabolic dysregulation.

New oral agents for treating dyslipidemia

PURPOSE OF REVIEW

We provide an overview of orally administered lipid-lowering therapies under development.

RECENT FINDINGS

Recent data support statins for intermediate risk primary prevention, and ezetimibe for high-risk secondary prevention. Novel agents in development include bempedoic acid and gemcabene, and work continues on one remaining cholesteryl ester transfer protein inhibitor, anacetrapib, to determine whether this class can reduce cardiovascular risk. Selective peroxisome proliferator-activated receptor modulators such as K-877 are under study to determine whether they have an advantage over older fibrates. Diacylglycerol transferase inhibitors such as pradigastat appear to have potent triglyceride-lowering effects, even for patients with familial chylomicronemia syndrome. Finally, novel ω-3 preparations are available with significant triglyceride lowering, although their role in therapy remains unclear.

SUMMARY

Statins will remain the backbone of lipid-lowering therapy, although several novel oral agents are promising. The common theme across drugs in development is the demonstration of good lipid-lowering effect, although lacking cardiovascular outcomes data, which will likely be necessary before any of them, can be recommended or approved for widespread use.

Metabolic control of epigenetics in cancer

Alterations in the epigenome and metabolism both affect molecular rewiring in cancer cells and facilitate cancer development and progression. However, recent evidence suggests the existence of important bidirectional regulatory mechanisms between metabolic remodelling and the epigenome (specifically methylation and acetylation of histones) in cancer. Most chromatin-modifying enzymes require substrates or cofactors that are intermediates of cell metabolism. Such metabolites, and often the enzymes that produce them, can transfer into the nucleus, directly linking metabolism to nuclear transcription. We discuss how metabolic remodelling can contribute to tumour epigenetic alterations, thereby affecting cancer cell differentiation, proliferation and/or apoptosis, as well as therapeutic responses.

Progress in the care of common inherited atherogenic disorders of apolipoprotein B metabolism

Familial hypercholesterolaemia, familial combined hyperlipidaemia (FCH) and elevated lipoprotein(a) are common, inherited disorders of apolipoprotein B metabolism that markedly accelerate the onset of atherosclerotic cardiovascular disease (ASCVD). These disorders are frequently encountered in clinical lipidology and need to be accurately identified and treated in both index patients and their family members, to prevent the development of premature ASCVD. The optimal screening strategies depend on the patterns of heritability for each condition. Established therapies are widely used along with lifestyle interventions to regulate levels of circulating lipoproteins. New therapeutic strategies are becoming available, and could supplement traditional approaches in the most severe cases, but their long-term cost-effectiveness and safety have yet to be confirmed. We review contemporary developments in the understanding, detection and care of these highly atherogenic disorders of apolipoprotein B metabolism.

Effect of ETC-1002 on Serum Low-Density Lipoprotein Cholesterol in Hypercholesterolemic Patients Receiving Statin Therapy

ETC-1002 is an oral, once-daily medication that inhibits adenosine triphosphate citrate lyase, an enzyme upstream of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, to reduce cholesterol biosynthesis. ETC-1002 monotherapy has demonstrated significant reduction in low-density lipoprotein cholesterol (LDL-C) compared with placebo in phase 2 studies. The objective of this study was to compare the lipid-lowering efficacy of ETC-1002 versus placebo when added to ongoing statin therapy in patients with hypercholesterolemia. This phase 2b, multicenter, double-blind trial (NCT02072161) randomized 134 hypercholesterolemic patients (LDL-C, 115 to 220 mg/dl) on stable background statin therapy to 12 weeks of add-on treatment with ETC-1002 120 mg, ETC-1002 180 mg, or placebo. The primary efficacy end point was the percent change in calculated LDL-C from baseline to week 12. For LDL-C, the least-squares mean percent change ± standard error from baseline to week 12 was significantly greater with ETC-1002 120 mg (-17 ± 4%, p = 0.0055) and ETC-1002 180 mg (-24 ± 4%, p <0.0001) than placebo (-4 ± 4%). ETC-1002 also dose dependently reduced apolipoprotein B by 15% to 17%, non-high-density lipoprotein cholesterol by 14% to 17%, total cholesterol by 13% to 15%, and LDL particle number by 17% to 21%. All these reductions in ETC-1002-treated cohorts were significantly greater than those with placebo. Rates of adverse events (AEs), muscle-related AEs, and discontinuations for AEs with ETC-1002 were similar to placebo. In conclusion, ETC-1002 120 mg or 180 mg added to stable statin therapy significantly reduced LDL-C compared to placebo and has a similar tolerability profile.

Lipid-Lowering Drug Therapy for CVD Prevention: Looking into the Future

Over the past three decades, statins have become first-line treatment for reducing LDL cholesterol (LDL-C) and cardiovascular disease (CVD). They have provided a clear, robust, and reproducible relationship between the absolute LDL-C reduction and the decrease in CVD; every 1 mmol/L (~40 mg/dL) in LDL-C reduction results in a 22 % decrease in CVD events. This relationship has recently been extended to reduction in LDL-C with a non-statin, ezetimibe, on top of statin therapy, further consolidating LDL-C as the cornerstone in CVD risk reduction. Despite these two effective and safe LDL-C-lowering drugs, there remains a need for additional drugs to reduce LDL-C, the focus of this review which covers agents which produce sufficient LDL-C reduction to potentially help address this unmet need and are either recently approved or currently in clinical trials.

Treatment with ETC-1002 alone and in combination with ezetimibe lowers LDL cholesterol in hypercholesterolemic patients with or without statin intolerance

BACKGROUND

ETC-1002 is an oral, once-daily, first-in-class medication being developed to treat hypercholesterolemia.

OBJECTIVES

To compare 2 doses of ETC-1002, alone or combined with ezetimibe 10 mg (EZE), vs EZE monotherapy for lowering low-density lipoprotein cholesterol (LDL-C).

METHODS

This phase 2b, multicenter, double-blind trial-evaluated hypercholesterolemic patients (LDL-C, 130 to 220 mg/dL) with (n = 177) or without (n = 171) muscle-related intolerance to ≥2 statins; 1 at lowest approved dose. Subjects were randomized to 12-week treatment with ETC-1002 120 mg or ETC-1002 180 mg alone, EZE alone, ETC-1002 120 mg plus EZE, or ETC-1002 180 mg plus EZE.

RESULTS

EZE alone lowered LDL-C by 21%, whereas ETC-1002 monotherapy with 120 mg or 180 mg reduced LDL-C by 27% (P = .0008 vs EZE) and 30% (P < .0001 vs EZE), respectively. The combination of ETC-1002, 120 mg or 180 mg plus EZE reduced LDL-C by 43% and 48%, respectively (both P < .0001 vs EZE). ETC-1002 alone or combined with EZE also reduced non-high-density lipoprotein cholesterol, total cholesterol, apolipoprotein B, LDL particle number, and high-sensitivity C-reactive protein compared with EZE alone. Across all treatment groups, statin-intolerant patients reported more muscle-related adverse events than did statin-tolerant patients. ETC-1002 was safe and well tolerated, and rates of muscle-related adverse events were similar in all treatment groups.

CONCLUSIONS

In patients with and without statin intolerance, daily treatment with ETC-1002 120 mg and 180 mg alone or with EZE reduced LDL-C more than EZE alone and had a similar tolerability profile (NCT01941836).

Adenosine triphosphate citrate lyase: Emerging target in the treatment of dyslipidemia

Despite major advances in pharmacologic therapy over the last few decades, dyslipidemia remains a prevalent, insufficiently recognized, and undercontrolled risk factor for cardiovascular disease. Statins are the mainstay of hypercholesterolemia treatment, but because of adherence and tolerability issues that limit dose titration, there is a need for additional therapies with good efficacy and better tolerability. Adenosine triphosphate (ATP) citrate lyase, a cytoplasmic enzyme responsible for the generation of acetyl coenzyme A for the de novo synthesis of fatty acids and cholesterol, is a very interesting molecular target for the reduction of plasma lipids. Furthermore, ATP citrate lyase inhibition may be accompanied by activation of 5'-adenosine monophosphate-activated protein kinase, a key signaling molecule that acts a central hub in cellular metabolic regulation. ETC-1002 is a small molecule inhibitor of ATP citrate lyase that also activates 5'-adenosine monophosphate-activated protein kinase, effectively reducing low-density lipoprotein cholesterol and inducing some other positive metabolic changes. Recent evidence from phase I and II clinical trials in humans has shown a positive efficacy and safety profile of ETC-1002, with low-density lipoprotein cholesterol reductions similar to those attainable by usual doses of many statins and with no major apparent side effects. These results potentially introduce a new family of medications that may expand our therapeutic arsenal against hypercholesterolemia.