Cholesterol Ester Transfer Protein Inhibitors Research Articles

Novel Therapeutic Approaches for the Management of Elevated Lipoprotein(a): From Traditional Agents to Future Treatment Options.

Cardiovascular disease is the leading cause of mortality worldwide. Despite the availability of effective low-density lipoprotein cholesterol (LDL-C) lowering agents, an increased cardiovascular risk is still observed in individuals with therapeutic LDL-C levels. One of these cardiovascular risk factors is elevated plasma lipoprotein(a) (Lp(a)) concentration, which maintains chronic inflammation through the increased presence of oxidized phospholipids on its surface. In addition, due to its 90 percent homology with the fibrinolytic proenzyme plasminogen, Lp(a) exhibits atherothrombotic effects. These may also contribute to the increased cardiovascular risk in individuals with high Lp(a) levels that previous epidemiological studies have shown to exist independently of LDL-C and other lipid parameters. In this review, the authors overview the novel therapeutic options to achieve effective Lp(a) lowering treatment, which may help to define tailored personalized medicine and reduce the residual cardiovascular risk in high-risk patients. Agents that increase LDL receptor expression, including statins, proprotein convertase subtilisin kexin type 9 inhibitors, and LDL production inhibitors, are also discussed. Other treatment options, e.g., cholesterolester transfer protein inhibitors, nicotinic acid derivatives, thyroid hormone mimetics, lipoprotein apheresis, as well as apolipoprotein(a) reducing antisense oligonucleotides and small interfering RNAs, are also evaluated.

Advances in Treatment of Dyslipidemia.

Dyslipidemias have emerged as prevalent disorders among patients, posing significant risks for the development and progression of cardiovascular diseases. These conditions are characterized by elevated levels of total cholesterol (TC), triglycerides (TGs), and low-density lipoprotein cholesterol (LDL-C). This review delves into the current treatment approach, focusing on equalizing these parameters while enhancing the overall quality of life for patients. Through an extensive analysis of clinical trials, we identify disorders that necessitate alternative treatment strategies, notably familial hypercholesterolemia. The primary objective of this review is to consolidate existing information concerning drugs with the potential to revolutionize dyslipidemia management significantly. Among these promising pharmaceuticals, we highlight alirocumab, bempedoic acid, antisense oligonucleotides, angiopoietin-like protein inhibitors, apolipoprotein C-III (APOC3) inhibitors, lomitapide, and cholesterol ester transfer protein (CETP) inhibitors. Our review demonstrates the pivotal roles played by each of these drugs in targeting specific parameters of lipid metabolism. We outline the future landscape of dyslipidemia treatment, envisaging a more tailored and effective therapeutic approach to address this widespread medical concern.

Targeting PCSK9 and Beyond for the Management of Low-Density Lipoprotein Cholesterol.

Reducing low-density lipoprotein cholesterol (LDL-C) levels is crucial to the prevention of atherosclerotic cardiovascular disease (ASCVD). However, many patients, especially those at very high ASCVD risk or with familial hypercholesterolemia (FH), do not achieve target LDL-C levels with statin monotherapy. The underutilization of novel lipid-lowering therapies (LLT) globally may be due to cost concerns or therapeutic inertia. Emerging approaches have the potential to lower LDL-C and reduce ASCVD risk further, in addition to offering alternatives for statin-intolerant patients. Shifting the treatment paradigm towards initial combination therapy and utilizing novel LLT strategies can complement existing treatments. This review discusses innovative approaches including combination therapies involving statins and agents like ezetimibe, bempedoic acid, cholesterol ester transfer protein (CETP) inhibitors as well as strategies targeting proprotein convertase subtilisin/kexin type 9 (PCSK9) and angiopoietin-like protein 3 (ANGPTL3) inhibition. Advances in nucleic acid-based therapies and gene editing are innovative approaches that will improve patient compliance and adherence. These strategies demonstrate significant LDL-C reductions and improved cardiovascular outcomes, offering potential for optimal LDL-C control and reduced ASCVD risk. By addressing the limitations of statin monotherapy, these approaches provide new management options for elevated LDL-C levels.

New Cholesteryl Ester Transfer Protein from Indonesian Herbal Plants as Candidate Treatment of Cardiovascular Disease

BACKGROUND: There is a strong negative relationship between high-density lipoprotein cholesterol (HDL-C) and the risk of cardiovascular disease (CVD). Cholesterol ester transfer protein (CETP) is a glycoprotein transporter that transfers cholesterol esters to very low-density lipoprotein and low-density lipoprotein cholesterol (LDL-C). The CETP inhibitor is a new strategy against CVD because of its ability to increase HDL-C. Various Indonesian plants have not been optimally used, and in silico phytochemical screening of these plants showing potential as CETP inhibitors is still limited. AIM: This study for exploring Indonesian phytochemicals as CETP inhibitors for new CVD treatments. METHODS: We screened 457 phytochemicals registered in the herbal database and met Lipinski’s rule of five. Their molecular structures were downloaded from the PubChem database. The three-dimensional structures of CETP and dalcetrapib (the CETP inhibitor standard) were obtained from a protein data bank (http://www.rcsb.org/pdb/) with the 4EWS code and ZINC database with the ZINC03976476 code, respectively. CETP–dalcetrapib binding complexes were validated 5 times using AutoDock Vina 1.1.2 software. Interactions between CETP and phytochemicals were molecularly docked with the same software and visualized using Pymol 1.8× software. RESULTS: Dalcetrapib had a docking score of −9.22 kcal/mol and bound to CETP at Ser230 and His232 residues. The 11 phytochemicals had lower binding scores than dalcetrapib, but only L-(+)-tartaric acid, chitranone, and oxoxylopine could interact with CETP at the Ser230 residue. These are commonly found in Tamarindus indica, Plumbago zeylanica, and Annona reticulata, respectively. CONCLUSION: L-(+)-Tartaric acid, chitranone, and oxoxylopine show potential as CETP inhibitors in silico.

Impact of High-Density Lipoproteins on Sepsis.

Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to infection. Here, we review the impact of high-density lipoproteins (HDL) on sepsis from the perspective of biochemistry and pathophysiology, epidemiological research, and intervention studies in animals. Pathogen lipid moieties are major ligands for innate immunity receptors, such as toll-like receptors. The binding of pathogen-associated lipids to lipoproteins leads to sequestration, neutralization, and inactivation of their pro-inflammatory effects. Lipoproteins constitute an arm of the innate immune system. Pathogen-associated lipids can be removed from the body via the reverse lipopolysaccharide transport pathway in which HDL play a key role. Independent of the capacity for sequestration, the direct anti-inflammatory effects of HDL may counteract the development of sepsis. Mendelian randomization research using genetic variants associated with HDL cholesterol as an instrumental variable was consistent with a probable causal relationship between increased HDL cholesterol levels and decreased risk of infectious hospitalizations. Low HDL cholesterol independently predicts an adverse prognosis in sepsis both in observational epidemiology and in Mendelian randomization studies. Several HDL-associated enzymes, including phospholipid transfer protein (PLTP) and cholesterol ester transfer protein (CETP), undergo profound changes during sepsis. Potential HDL-directed interventions for treatment of sepsis include apolipoprotein A-I-based therapies, recombinant PLTP, and CETP inhibition.

Comparison of low-density lipoprotein cholesterol equations in patients with dyslipidaemia receiving cholesterol ester transfer protein inhibition

Abstract Background Low-density lipoprotein (LDL-C) lowering is imperative in cardiovascular disease prevention. Effectively translating the evidence for LDL-C lowering to maximize clinical and public health benefits depends on the availability of accurate LDL-C results from clinical laboratories to guide therapy. Furthermore, prior work has raised the possibility that cholesterol esterase transfer protein (CETP) inhibition could interfere with accurate assessment of LDL-C. Purpose We aimed to compare accuracy of three clinically implemented LDL-C equations in a clinical trial of CETP inhibition. Methods Men and women aged 18–75 years with dyslipidaemia were recruited from 17 sites in the Netherlands and Denmark. Patients were randomly assigned to one of nine groups using various combinations of the CETP inhibitor TA-8995, statin therapy, and placebo. In pooled measurements over 12 weeks, we calculated LDL-C by the Friedewald, Martin/Hopkins, and Sampson equations, and compared values with preparative ultracentrifugation (PUC) LDL-C as the reference measure (also known as “beta quantification”). Based on prior literature and dyslipidaemia guidelines, we examined correct classifications across the LDL-C 1.81 mmol/L cutpoint in the subgroup of patients with triglycerides of 1.69–4.51 mmol/L. Results The analysis included 242 patients contributing 921 observations. The full distributions of differences between LDL-C estimates and PUC are shown in Figure 1. Overall median LDL-C differences between estimates and PUC were small: Friedewald, 0.00 (25th, 75th: −0.10, 0.08) mmol/L; Martin/Hopkins, 0.02 (−0.08, 0.10) mmol/L; and Sampson, 0.05 (−0.03, 0.15) mmol/L. In the subgroup with estimated LDL-C <1.81 mmol/L and triglycerides 1.69–4.51 mmol/L, the Friedewald equation underestimated LDL-C with a median difference versus PUC of −0.25 (−0.33, −0.10) mmol/L, whereas the Martin/Hopkins equation corrected this issue with a median difference of 0.00 (−0.08, 0.10) mmol/L and the Sampson equation showed tendency towards underestimation with a median difference of −0.06 (−0.13, 0.00) mmol/L. In patients with triglyceride levels of 1.69–4.51 mmol/L, Figure 2 shows the proportion of LDL-C levels classified by the equations as < or ≥1.81 mmol/L that were correctly classified when compared with PUC. All three equations showed >95% accuracy when estimated LDL-C levels were ≥1.81 mmol/L. However, the proportion of LDL-C observations <1.81 mmol/L that were correctly classified compared with PUC was 71.4% by Friedewald versus 100.0% by Martin/Hopkins and 93.1% by Sampson. Conclusion In Europeans with dyslipidaemia, our analysis shows improved accuracy in LDL-C when using contemporary LDL-C equations over the Friedewald equation, particularly when using the Martin/Hopkins equation. High levels of accuracy with the Martin/Hopkins equation were seen in individuals treated with CETP inhibition and even in the context of low LDL-C and high triglyceride levels. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): Dezima and NewAmsterdam Pharma

Acquiring novel chemicals by overexpression of a transcription factor DibT in the dibenzodioxocinone biosynthetic cluster in Pestalotiopsis microspora.

The endophytic fungus Pestalotiopsis microspora has drawn attention due to its production of dibenzodioxocinones which are a new class of inhibitors of cholesterol ester transfer protein (CETP). Previous studies showed that the pks8 gene cluster is responsible for the biosynthesis of dibenzodioxocinones in P. microspora. Disrupting the gene encoding a transcription factor DibT, which contains a zinc-finger functional domain, led to a significant decrease in the production of dibenzodioxocinones. To further investigate the function of DibT in the expression of pks8 cluster, we constructed dibT-overexpressing strains and found that all genes in the pks8 cluster were upregulated and the yields of dibenzodioxocinones were significantly increased. Moreover, function of DibT was required for the expression of most PKS genes outside of pks8 clusters, i.e., 43 out of 48 defined PKS genes, and boosted pigmentation of the mycelium and conidia. Still, we identified a new dibenzodioxocinone, 1',2'-dimethyl-3'-formyl- 1',2'-dehydropenicillide (6) and a previously known, but conditionally synthesized dibenzodioxocinone, 3'-methoxy-1',2'-dehydropenicillide (4) from the overexpression strains. Our results show that DibT was the key transcription factor in the expression of pks8 cluster and still has a wide effect on the expression of PKS genes in the genome. This work provides information for the regulation of dibenzodioxocinone biosynthesis and may be helpful for the development of new CETP inhibitors.

High-density lipoprotein cholesterol — friend or enemy?

The article provides a review of the literature on the effect of excess and deficiency of high-density lipoprotein cholesterol on the prevention and treatment of cardiovascular pathology. Information about high-density lipoproteins structure, function, antiatherogenic role and the prospect of using various high-density lipoproteins subclasses in the pharmacotherapy of dyslipidemic conditions are also described. It is proven that a lowered level of such cholesterol is a predictor of cardiovascular disease. At the same time, many observations confirm the correlation between elevated high-density lipoprotein levels and mortality from myocardial infarction and other acute cardiovascular conditions. In large studies, the use of cholesterol ester transfer protein inhibitors and other drugs increased the level of high-density lipoprotein, but the unreduced risk of cardiovascular disease confirms the lack of positive results from the use as a therapeutic target. In addition, it was found that the composition of high-density lipoprotein cholesterol protein differs in healthy and diseased people: it becomes dysfunctional, losing its antioxidant and anti-inflammatory properties in diseased individuals. The atheroprotective activity of properly functioning high-density lipoprotein cholesterol is often impaired in clinical situations associated with oxidative stress. In these cases, high-density lipoproteins can have some changes, and even if the quantity is within the normal range, the quality is no longer the same. Thus, it is necessary to identify a better therapeutic target than high-density lipoprotein cholesterol levels, as there is currently insufficient clinical trial data to recommend targeted high-density lipoprotein therapy.

HDL and Cholesterol Ester Transfer Protein (CETP).

Cholesterol ester transfer protein (CETP) is important clinically and is one of the major targets in cardiovascular disease studies. With high conformational flexibility, its tunnel structure allows unforced movement of high-density lipoproteins (HDLs), VLDLs, and LDLs. Research in reverse cholesterol transports (RCT) reveals that the regulation of CETP activity can change the concentration of cholesteryl esters (CE) in HDLs, VLDLs, and LDLs. These molecular insights demonstrate the mechanisms of CETP activities and manifest the correlation between CETP and HDL. However, animal and cell experiments focused on CETP give controversial results. Inhibiting CETP is found to be beneficial to anti-atherosclerosis in terms of increasing plasma HDL-C, while it is also claimed that CETP weakens atherosclerosis formation by promoting RCT. Currently, the CETP-related drugs are still immature. Research on CETP inhibitors is targeted at improving efficacy and minimizing adverse reactions. As for CETP agonists, research has proved that they also can be used to resist atherosclerosis.

Elevated Lipoprotein(a): Background, Current Insights and Future Potential Therapies.

Lipoprotein(a) forms a subfraction of the lipid profile and is characterized by the addition of apolipprotein(a) (apo(a)) to apoB100 derived particles. Its levels are mostly genetically determined inversely related to the number of protein domain (kringle) repeats in apo(a). In epidemiological studies, it shows consistent association with cardiovascular disease (CVD) and most recently with extent of aortic stenosis. Issues with standardizing the measurement of Lp(a) are being resolved and consensus statements favor its measurement in patients at high risk of, or with family histories of CVD events. Major lipid-lowering therapies such as statin, fibrates, and ezetimibe have little effect on Lp(a) levels. Therapies such as niacin or cholesterol ester transfer protein (CETP) inhibitors lower Lp(a) as well as reducing other lipid-related risk factors but have failed to clearly reduce CVD events. Proprotein convertase subtilisin kexin-9 (PCSK9) inhibitors reduce cholesterol and Lp(a) as well as reducing CVD events. New antisense therapies specifically targeting apo(a) and hence Lp(a) have greater and more specific effects and will help clarify the extent to which intervention in Lp(a) levels will reduce CVD events.

Advancing Beyond Failed High-density Lipoprotein Clinical Trials to Pharmacogenetic Studies of ADCY9 and Cholesterol Ester Transfer Protein Inhibition.

Atherosclerosis has been effectively avoided with many therapies that lower low-density lipoprotein cholesterol. However, significant cardiovascular burden remains. The effect of raising high-density lipoprotein (HDL) has been confounded by other factors (such as lowering triglycerides or LDL) and unsuccessful when attempting to solely increase HDL. Reviewing the available data, the failures of previous strategies may reflect the complexity of HDL in human metabolism and the heterogeneity of human genetics. dal-GenE (NCT02525939) represents the first large cardiovascular outcomes study to use a selective genomic test to identify the target population most likely to receive therapeutic benefit and uses a cholesterol ester transfer protein inhibitor, dalcetrapib. Both the cholesterol ester transfer protein target and the ADCY9 polymorphism identified by the diagnostic test are based on inheritance and an evolving understanding of inborn risk. Selective treatment of subpopulations may be the key to the conundrum of HDL as an actionable risk factor.

Structure-Activity Relationship and Pharmacological Evaluation of 4-[2-(3,5-Dimethoxy-phenyl)-vinyl]-phenylacetamide as Cholesterol Ester Transfer Protein Inhibitor

Cholesterol ester transfer protein is a plasma glycoprotein synthesized by the liver. Inhibitors of this protein have been researched to treat dyslipidemia. The purpose of this study was to use the computer-aided drug design technique to screen the structures of compounds from the traditional Chinese medicine database and optimize them as new cholesterol-lowering drugs. Molecular docking using 248 chemical compositions of traditional Chinese medicines with cholesterol ester transfer protein was performed. The parent structure “resveratrol” was selected and optimized as the matrix structure. A series of 4-[2-(3,5-dimethoxy-phenyl)-vinyl]-phenylamine analogues were synthesized and characterized by spectroscopic and spectrometric methods.

Synthetic transformations and biological screening of benzoxazole derivatives: A review

AbstractThe presence of benzoxazole moiety in most of the heterocyclic compounds is well reported. The present literature review mainly highlights the novel synthetic transformation and describes the biological potential of most of the heterocyclic compounds by virtue of presence of benzoxazole framework. Most of the researchers have revealed that benzoxazole derivatives exhibit significant antibacterial, anti‐inflammatory, antifungal, anticancer, analgesic, antiviral, anti‐tubercular, and anthelmintic activities. Benzoxazole moieties also act as tyrosinase inhibitor and cholesterol ester transfer protein inhibitor. This literature review may provide an opportunity to the chemists to design new derivatives of benzoxazole that proved to be the successful agent in view of safety, effectiveness, and efficacy.

The Rise and Fall "ing" of the HDL Hypothesis.

Earlier epidemiological studies have shown an inverse correlation between high-density lipoprotein cholesterol (HDLc) and coronary heart disease (CHD). This observation along with the finding that reverse cholesterol transport is mediated by HDL, supported the hypothesis that the HDL molecule has a cardioprotective role. More recently, epidemiological data suggest a U-shaped curve correlating HDLc and CHD. In addition, randomized clinical trials of drugs that significantly increase plasma HDLc levels, such as nicotinic acid and cholesterol ester transfer protein (CETP) inhibitors failed to show a reduction in major adverse cardiovascular events. These observations challenge the hypothesis that HDL has a cardioprotective role. It is possible that HDL quality and function is optimal only when de novo synthesis of apo A-I occurs. Inhibition of turnover of HDL with currently available agents yields HDL molecules that are ineffective in reverse cholesterol transport. To test this hypothesis, newer therapeutic drugs that increase de novo production of HDL and apo A-I should be tested in clinical trials.

P719Endothelial expression of adenylate cyclase type 9 (Adcy9) regulates endothelial cell signalling and vasodilation

Abstract Background/Introduction The clinical benefits of the cholesterol ester transfer protein (CETP) inhibitor dalcetrapib are dependent on the ADCY9 gene, which encodes adenylate cyclase (AC) type 9 (AC9). AC9 is one of nine membrane-bound isoforms of AC producing cyclic adenosine monophosphate (cAMP). We demonstrated that Adcy9 inactivation in the mouse protects from atherosclerosis, but only in absence of CETP. Adcy9 inactivation is also associated with improved endothelial function, including greater endothelial-dependent vasodilation (EDV) in response to acetylcholine (ACh). This suggests that Adcy9 may control endothelial Ca2+, an essential mediator of endothelial cell (EC) signalling. We hypothesized that Adcy9 is expressed in the endothelium and controls EC signalling. Purpose Our aim was to study AC9 expression in the vascular endothelium and the role of AC9 expression on endothelial cAMP signalling and Ca2+ dynamics. Methods The effects of Adcy9 inactivation were studied using wild-type (WT) and Adcy9-inactivated (Adcy9Gt/Gt) mice and siRNA-mediated inactivation of ADCY9 in human coronary artery endothelial cells (HCAEC). In the mouse, AC9 expression was quantified in whole aorta (± endothelium) and primary cultures of lung EC (LEC) by Western blot. Endothelial Ca2+ pulsars were monitored in mouse femoral arteries in response to acetylcholine (ACh, 10 μM). cAMP accumulation to AC activators VIP and forskolin were measured in LEC and HCAEC. EDV to VIP was studied ex vivo in mouse femoral arteries using pressurized arteriography. Results AC9 is expressed in LEC and the aorta, and its detection in the latter decreased by 33% after mechanical removal of the endothelium (P<0.05). AC activation with forskolin (10–4 M) in LEC led to increased cAMP accumulation in response to Adcy9 inactivation (WT: 1129±138 pmol cAMP/mg of protein, Adcy9Gt/Gt: 1965±169, n=3; P<0.01). ADCY9 inactivation in HCAEC also increased cAMP accumulation to forskolin 10–4M (control siRNA: 85±17, ADCY9 siRNA: 150±6, n=3; P<0.01). In LEC, receptor-dependent accumulation of cAMP to VIP (10–5 M) was higher in Adcy9Gt/Gt (1509±258)) compared to WT (915±170, n=3; P<0.05) mice. In mouse femoral arteries, VIP-induced maximal vasodilation was increased by Adcy9 inactivation in the presence of the endothelium (Adcy9Gt/Gt: 85±4%, n=6; WT: 52±9%, n=5, P<0.05), but not in its absence (Adcy9Gt/Gt: 67±12%, n=6 and WT: 59±15%, n=5). In the femoral artery endothelium, ACh increased Ca2+ pulsar frequency more in Adcy9Gt/Gt (243±32%, n=4) than in WT (178±19%, n=5; P<0.05) mice. Conclusion ADCY9 is expressed in the endothelium, and its inactivation potentiates endothelial cell Ca2+ dynamics, cAMP accumulation and VIP-induced vasodilation. We therefore identify ADCY9 as a new molecular pathway regulating endothelial-dependent vasodilation. This suggests that ADCY9's endothelial biology could be involved in the ADCY9 genotype-dependent clinical effects of dalcetrapib. Acknowledgement/Funding DalCor

Potential Inhibitors of the Activity of the Cholesterol-Ester Transfer Protein.

The cholesterol-ester transfer protein (CETP) exchanges lipids between high-density lipoproteins (HDLs) and low-density lipoproteins (LDLs). The excessive transport of lipids from HDLs to LDLs mediated by this protein can cause an alteration in the deposition of lipoproteins onto the arterial walls, thus promoting the development of arteriosclerosis. Different CETP inhibitors have been tested in recent years, but none has been confirmed as being effectively palliative for the disease. We employed in silico databases and molecular docking as a computational method to predict how potential CETP inhibitors could interact with the active site of the CETP protein. Upon previously comparing two computer software packages to determine which generated a greater number of accurate CETP-inhibitor-complex structures, we chose the more appropriate program for our studies. We then abstracted a series of databases of known CETP inhibitors and noninhibitors exhibiting different 50% concentrations of CETP-inhibitory (INH) activity, to generate virtual structures for docking with different combinations of the CETP receptor. From this process, we obtained as the most suitable structure 4F2A_1OB_C_PCW-it accordingly having a greater area under the receiver operating characteristic curve. The molecular docking of known compounds in comparison with the respective conformation of this inhibitor enabled us to obtain ΔGs (in kcal/mol) from which data we made a first exploration of unknown compounds for CETP-INH activity. Thus, the 4F2A_1OB_C_PCW structure was docked with DrugBank-Approved commercial compounds in an extensive database, whose status had already been established from pharmacokinetics and toxicology. In this study, we present a group of potential compounds as CETP-inhibitor candidates.

Systematic Review for the 2018 AHA/ACC/AACVPR/AAPA/ABC/ACPM/ADA/AGS/APhA/ASPC/NLA/PCNA Guideline on the Management of Blood Cholesterol: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines.

The 2013 American College of Cardiology/American Heart Association guidelines for the treatment of blood cholesterol found little evidence to support the use of nonstatin lipid-modifying medications to reduce atherosclerotic cardiovascular disease (ASCVD) events. Since publication of these guidelines, multiple randomized controlled trials evaluating nonstatin lipid-modifying medications have been published. We performed a systematic review to assess the magnitude of benefit and/or harm from additional lipid-modifying therapies compared with statins alone in individuals with known ASCVD or at high risk of ASCVD. We included data from randomized controlled trials with a sample size of >1 000 patients and designed for follow-up >1 year. We performed a comprehensive literature search and identified 10 randomized controlled trials for intensive review, including trials evaluating ezetimibe, niacin, cholesterol-ester transfer protein inhibitors, and PCSK9 inhibitors. The prespecified primary outcome for this review was a composite of fatal cardiovascular events, nonfatal myocardial infarction, and nonfatal stroke. The cardiovascular benefit of nonstatin lipid-modifying therapies varied significantly according to the class of medication. There was evidence for reduced ASCVD morbidity with ezetimibe and 2 PSCK9 inhibitors. Reduced ASCVD mortality rate was reported for 1 PCSK9 inhibitor. The use of ezetimibe/simvastatin versus simvastatin in IMPROVE-IT (Improved Reduction of Outcomes: Vytorin Efficacy International Trial) reduced the primary outcome by 1.8% over 7 years (hazard ratio: 0.90; 95% CI: 0.84-0.96], 7-year number needed to treat: 56). The PSCK9 inhibitor evolocumab in the FOURIER study (Further Cardiovascular Outcomes Research with PCSK9 Inhibition in Subjects with Elevated Risk) decreased the primary outcome by 1.5% over 2.2 years (hazard ratio: 0.80; 95% CI: 0.73-0.88; 2.2=year number needed to treat: 67). In ODYSSEY OUTCOMES (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab), alirocumab reduced the primary outcome by 1.6% over 2.8 years (hazard ratio: 0.86; 95% CI: 0.79-0.93; 2.8-year number needed to treat: 63). For ezetimibe and the PSCK9 inhibitors, rates of musculoskeletal, neurocognitive, gastrointestinal, or other adverse event risks did not differ between the treatment and control groups. For patients at high risk of ASCVD already on background statin therapy, there was minimal evidence for improved ASCVD risk or adverse events with cholesterol-ester transfer protein inhibitors. There was no evidence of benefit for the addition of niacin to statin therapy. Direct comparisons of the results of the 10 randomized controlled trials were limited by significant differences in sample size, duration of follow-up, and reported primary outcomes. In a systematic review of the evidence for adding nonstatin lipid-modifying therapies to statins to reduce ASCVD risk, we found evidence of benefit for ezetimibe and PCSK9 inhibitors but not for niacin or cholesterol-ester transfer protein inhibitors.

Small Dense Low-Density Lipoprotein: Biomarker or Potential Drug Target?

AbstractIschemic heart disease is currently an epidemic affecting individuals worldwide. Increased incidence along with earlier onset of disease has led to the constant search for biomarkers that will help in earlier identification and treatment of at risk individuals. Small dense low-density lipoprotein (sdLDL) is the atherogenic subtype of low-density lipoprotein (LDL). It is smaller in size and higher in density in comparison to other LDL subtypes. Higher levels of sdLDL have beenfound to be associated with increased incidence of ischemic heart disease and adverse outcomes. Properties including decreased resistance to oxidative stress and prolonged residence time in the circulation account for its increased atherogenic potential. Hence intervention approaches targeting sdLDL directly in at risk individuals may be beneficial.Genetic, lifestyle, and environmental factors affect sdLDL levels.But the main determining factor is the level of triglycerides (TGs). Higher TG levels are associated with higher levels of very low density lipoprotein (VLDL) 1 and sdLDL. Various drugs have been used for targeting sdLDL with varying outcomes; drugs tried out include statins, fibrates, niacin, cholesterol ester transfer protein inhibitors and sodium-glucose co-transporter-2 inhibitors. Future prospects include modification of enzymes involved in fatty acid and TG synthesis, for example, lipoprotein lipase and acyl CoA carboxylase. However, further research is still necessary to draw clear guidelines for sdLDL reduction therapy in coronary artery disease treatment and prevention.

An update on trials of novel lipid-lowering drugs.

A number of novel trials have assessed the efficacy of new lipid-lowering therapies in cardiovascular disease (CVD). Proprotein convertase subtilisin kexin-9 inhibitors reduce low-density lipoprotein cholesterol (LDL-C) by 50-55%. A CVD outcome trial in patients with acute coronary syndromes with evolocumab achieved a LDL-C of 0.8 mmol/l (31 mg/dl) and a 20% relative risk reduction in CVD events in 2.2 years. Cholesterol ester transfer protein inhibitors raise high-density lipoprotein cholesterol and can lower LDL-C. Anacetrapib reduced coronary artery disease events by 7%, but not wider composite CVD outcomes, in a population with chronic CVD with pretreatment LDL-C of 1.6 mmol/l (62 mg/dl). The conflicting outcomes of cholesterol ester transfer protein inhibitor trials means these compounds are not being developed further. Trials using lipid drugs targeting inflammation have previously been generally unsuccessful, but recent data on the interleukin-1B receptor antagonist canakinumab has proven the concept of intervention on inflammation in atherosclerosis by showing a reduction in acute coronary interventions, but at the predictable cost of increased infections. Despite the success of proprotein convertase subtilisin kexin-9 inhibition, the ability to achieve low LDL-C with off-patent medications and the costs of novel therapies will limit their use even in high-risk patients and confine them to the highest-risk sub-groups of patients.

Further options for treating lipids in people with diabetes: targeting LDL-cholesterol and beyond.

Diabetes is associated with increased cardiovascular disease (CVD) risk. Previous studies with statins have established that a 1 mmol/l reduction in LDL-cholesterol reduces CVD events by 21% over 5 years in people with diabetes. More recently, trials in people with acute coronary syndromes showed that ezetimibe reduced CVD events by 6% at 5 years and achieved a LDL-cholesterol of 1.6 mmol/l with better results in people with Type 2 diabetes. Several novel lipid-lowering therapies have recently been developed. Most data have been accumulated with proprotein convertase subtilisin kexin-9 (PCSK-9) inhibitors, which reduce LDL-cholesterol by 50-55%. A large CVD outcome trial with evolocumab, in which 40% of participants had diabetes, achieved a LDL-cholesterol of 0.8 mmol/l and showed a consistent 20% relative risk reduction within 2 years, including in people with diabetes. Trials to increase HDL-cholesterol using cholesterol ester transfer protein (CETP) inhibitors have generally underwhelmed. Although anacetrapib reduced coronary ischaemic events by 7% in a population with chronic CVD, more expansive CVD endpoints were not improved. The complex nature of CETP inhibitor trial outcomes means that these compounds are not being developed further. Trials targeting inflammation-associated lipids have been generally unsuccessful but recent data on the interleukin-1B receptor antagonist canakinumab have shown a reduction in acute coronary intervention, validating this target although at the cost of increased infections. The ability to achieve low LDL-cholesterol with off-patent medications and the costs of novel therapies will confine the use of novel agents to subgroups of people at highest risk of CVD.