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Anacetrapib, a cholesteryl ester transfer protein (CETP) inhibitor previously under development, exhibited an usually extended terminal half‐life and large food effect and accumulated in adipose tissue. Other CETP inhibitors have not shown such effects. Obicetrapib, a potent selective CETP inhibitor, is undergoing Phase III clinical development. Dedicated assessments were conducted in pre‐clinical and Phase I and II clinical studies of obicetrapib to examine the pharmacokinetic issues observed with anacetrapib. After 9 months of dosing up to 50 mg/kg/day in cynomolgus monkeys, obicetrapib was completely eliminated from systemic circulation and not detected in adipose tissue after a 13‐week recovery period. In healthy humans receiving 1–25 mg of obicetrapib, the mean terminal half‐life of obicetrapib was 148, 131, and 121 h at 5, 10, and 25 mg, respectively, and food increased plasma levels by ~1.6‐fold with a 10 mg dose. At the end of treatment in Phase II trials, mean plasma levels of obicetrapib ranged from 194.5 ng/mL with 2.5 mg to 506.3 ng/mL with 10 mg. Plasma levels of obicetrapib decreased by 92.2% and 98.5% at four and 15 weeks post‐treatment, respectively. Obicetrapib shows no clinically relevant accumulation, is minimally affected by food, and has a mean terminal half‐life of 131 h for the 10 mg dose. These data support once daily, chronic dosing of obicetrapib in Phase III trials for dyslipidemia management. [ABSTRACT FROM AUTHOR]

Background: Atherosclerosis is a multi-factorial disease, and low-density lipoprotein cholesterol (LDL-C) is a critical risk factor in developing atherosclerotic cardiovascular disease (ASCVD). Cholesteryl-ester transfer-protein (CETP), synthesized by the liver, regulates LDL-C and high-density lipoprotein cholesterol (HDL-C) through the bidirectional transfer of lipids. The novelty of CETP inhibitors (CETPis) has granted new focus towards increasing HDL-C, besides lowering LDL-C strategies. To date, five CETPis that are projected to improve lipid profiles, torcetrapib, dalcetrapib, evacetrapib, anacetrapib, and obicetrapib, have reached late-stage clinical development for ASCVD risk reduction. Early trials failed to reduce atherosclerotic cardiovascular occurrences. Given the advent of some recent large-scale clinical trials (ACCELERATE, HPS3/TIMI55-REVEAL Collaborative Group), conducting a meta-analysis is essential to investigate CETPis’ efficacy. Methods: We conducted a thorough search of randomized controlled trials (RCTs) that commenced between 2003 and 2023; CETPi versus placebo studies with a ≥6-month follow-up and defined outcomes were eligible. Primary outcomes: major adverse cardiovascular events (MACEs), cardiovascular disease (CVD)-related mortality, all-cause mortality. Secondary outcomes: stroke, revascularization, hospitalization due to acute coronary syndrome, myocardial infarction (MI). Results: Nine RCTs revealed that the use of a CETPi significantly reduced CVD-related mortality (RR = 0.89; 95% CI: 0.81–0.98; p = 0.02; I2 = 0%); the same studies also reduced the risk of MI (RR = 0.92; 95% CI: 0.86–0.98; p = 0.01; I2 = 0%), which was primarily attributed to anacetrapib. The use of a CETPi did not reduce the likelihood any other outcomes. Conclusions: Our meta-analysis shows, for the first time, that CETPis are associated with reduced CVD-related mortality and MI.

Cholesteryl ester transfer protein (CETP) inhibitors are a new class of therapeutics for dyslipidemia that simultaneously improve two major cardiovascular disease (CVD) risk factors: elevated low-density lipoprotein (LDL) cholesterol and decreased high-density lipoprotein (HDL) cholesterol. However, the detailed molecular mechanisms underlying their efficacy are poorly understood, as are any potential mechanistic differences among the drugs in this class. Herein, we used electron microscopy (EM) to investigate the effects of three of these agents (Torcetrapib, Dalcetrapib and Anacetrapib) on CETP structure, CETP-lipoprotein complex formation and CETP-mediated cholesteryl ester (CE) transfer. We found that although none of these inhibitors altered the structure of CETP or the conformation of CETP-lipoprotein binary complexes, all inhibitors, especially Torcetrapib and Anacetrapib, increased the binding ratios of the binary complexes (e.g., HDL-CETP and LDL-CETP) and decreased the binding ratios of the HDL-CETP-LDL ternary complexes. The findings of more binary complexes and fewer ternary complexes reflect a new mechanism of inhibition: one distal end of CETP bound to the first lipoprotein would trigger a conformational change at the other distal end, thus resulting in a decreased binding ratio to the second lipoprotein and a degraded CE transfer rate among lipoproteins. Thus, we suggest a new inhibitor design that should decrease the formation of both binary and ternary complexes. Decreased concentrations of the binary complex may prevent the inhibitor was induced into cell by the tight binding of binary complexes during lipoprotein metabolism in the treatment of CVD.

Introduction: Anacetrapib is a novel, powerful cholesteryl ester transfer protein (CETP) inhibitor with bidirectional lipid regulation, which was developed for dyslipidemia. The aim of this study is to evaluate the single- and multiple-dose pharmacokinetics (PK), safety and tolerability of anacetrapib in healthy Chinese subjects and assess the PK difference between Chinese and other populations. Methods: Forty subjects were enrolled in an open-label study consisting of three panels (50 mg single dose; 100 mg single dose followed by 100 mg once-daily multiple doses for 10 days; a 200 mg single dose). Safety and tolerability were evaluated by monitoring adverse events, laboratory safety tests, ECGs, vital signs and physical examination. PK were evaluated and compared with historical data in black and white subjects. Results: Anacetrapib was absorbed after administration of a single oral dose, with a median Tmax of 3.0–5.0 h and elimination half-life of 105.3–122.3 h. The AUC and Cmax of anacetrapib increased in a slightly less than dose-proportional manner over a dose range of 50–200 mg. Once-daily administration of 100 mg of anacetrapib for 10 days resulted in a median Tmax of 5.0 h with an apparent half-life of 193.7 h on Day 10 of multiple dosing. Anacetrapib accumulation ratios (Day 10 of multiple dosing/Day 1) were 1.39 (AUC0–24 h), 1.11 (Cmax) and 2.57 (C24 h). Conclusion: The PK properties of anacetrapib in Chinese subjects are comparable to those observed in the black population and in white subjects. Single and once-daily administration of anacetrapib was generally well tolerated in healthy Chinese subjects observed in this study. Trial Registration: chinadrugtrials.org.cn identifier number CTR20130983. [ABSTRACT FROM AUTHOR]

Cardiovascular disease (CVD) is one of the major causes of human death. Preliminary evidence indicates that the inhibition treatment of Cholesteryl Ester Transfer Protein (CETP) causes the most pronounced increase in HDL cholesterol reported so far. Merck has disclosed certain (4S,5R)-5-[3,5-bis(trifluoromethyl)phenyl]−4-methyl-1,3-oxazolidin-2-one derivatives, which show potent CETP inhibitory activity. Therefore, it would be desirable to develop computational models to facilitate the screening of these inhibitors. In the present work, quantitative structure–activity relationship (QSAR) models have been developed to predict the therapeutic potency of 108 derivatives of (4S,5R)-5-[3,5-bis(trifluoromethyl)phenyl]−4-methyl-1,3-oxazolidin-2-one: Multiple Linear Regression (MLR), Support Vector Regression (SVR) and Feedforward Neural Network using Particle Swarm Optimization (FNN-PSO). Six descriptors were selected using genetic algorithms, whereas, internal and external validation of the models was performed according to all available validation strategies. It was shown that CETP inhibitory activity is mainly governed by electronegativity, the structure of the molecule, and the electronic properties. The best results were obtained with the SVR model. The results obtained may assist in the design of new CETP inhibitors. [ABSTRACT FROM AUTHOR]

Belinda A Di Bartolo, Stephen J Nicholls South Australian Health and Medical Research Institute, University of Adelaide, Adelaide, SA, Australia Abstract: Cholesteryl ester transfer protein (CETP) facilitates movement of esterified cholesterol between high-density lipoproteins (HDLs) and apolipoprotein B-containing lipoproteins. By virtue of their ability to raise HDL cholesterol and lower low-density lipoprotein cholesterol, pharmacological inhibitors of CETP have received considerable attention as potential new agents in cardiovascular prevention. While early studies of CETP inhibitors have demonstrated a lack of clinical efficacy and potential toxicity, development of the potent CETP inhibitor, anacetrapib, has moved forward, with emerging evidence suggesting a role in reducing cardiovascular events. The experience with anacetrapib and its potential for use in clinical practice are reviewed here. Keywords: anacetrapib, CETP, lipids, atherosclerosis, cardiovascular disease

Abstract Anacetrapib is an inhibitor of cholesteryl ester transfer protein (CETP) previously under development as a lipid‐modifying agent that reduces LDL‐cholesterol and increases HDL‐cholesterol in hypercholesterolemic patients. Anacetrapib demonstrates a long terminal half‐life and accumulates in adipose tissue, which contributes to a long residence time of anacetrapib. Given our previous report that anacetrapib distributes into the lipid droplet of adipose tissue, we sought to understand whether anacetrapib affected adipose function, using a diet‐induced obese (DIO) mouse model. Following 20 weeks of treatment with anacetrapib (100 mg/kg/day), levels of the drug increased to approximately 0.6 mmol/L in white adipose tissue. This level of anacetrapib was not associated with any impairment in adipose functionality as evidenced by a lack of any reduction in biomarkers of adipose functionality (plasma adiponectin, leptin, insulin; adipose adiponectin, leptin mRNA). In DIO wild‐type (WT) mice treated with anacetrapib for 2 weeks and then subjected to 30% food restriction during washout to induce weight loss (18%) and fat mass loss (7%), levels of anacetrapib in adipose and plasma were not different between food restricted and ad lib‐fed mice. These data indicate that despite deposition and long‐term residence of ~0.6 mmol/L levels of anacetrapib in adipose tissue, adipose tissue function appears to be unaffected in mice. In addition, these data also indicate that even with severe caloric restriction and acute loss of fat mass, anacetrapib does not appear to be mobilized from the fat depot, thereby solidifying the role of adipose as a long‐term storage site of anacetrapib.

Anacetrapib is an inhibitor of cholesteryl ester transfer protein (CETP) previously under development as a lipid-modifying agent that reduces LDL-cholesterol and increases HDL-cholesterol in hypercholesterolemic patients. Anacetrapib demonstrates a long terminal half-life and accumulates in adipose tissue, which contributes to a long residence time of anacetrapib. Given our previous report that anacetrapib distributes into the lipid droplet of adipose tissue, we sought to understand whether anacetrapib affected adipose function, using a diet-induced obese (DIO) mouse model. Following 20 weeks of treatment with anacetrapib (100 mg/kg/day), levels of the drug increased to approximately 0.6 mmol/L in white adipose tissue. This level of anacetrapib was not associated with any impairment in adipose functionality as evidenced by a lack of any reduction in biomarkers of adipose functionality (plasma adiponectin, leptin, insulin; adipose adiponectin, leptin mRNA). In DIO wild-type (WT) mice treated with anacetrapib for 2 weeks and then subjected to 30% food restriction during washout to induce weight loss (18%) and fat mass loss (7%), levels of anacetrapib in adipose and plasma were not different between food restricted and ad lib-fed mice. These data indicate that despite deposition and long-term residence of ~0.6 mmol/L levels of anacetrapib in adipose tissue, adipose tissue function appears to be unaffected in mice. In addition, these data also indicate that even with severe caloric restriction and acute loss of fat mass, anacetrapib does not appear to be mobilized from the fat depot, thereby solidifying the role of adipose as a long-term storage site of anacetrapib. [ABSTRACT FROM AUTHOR]

Supplemental Digital Content is available in the text. Background: Exploratory analyses of previous randomized trials generated a hypothesis that the clinical response to cholesteryl ester transfer protein (CETP) inhibitor therapy differs by ADCY9 genotype, prompting the ongoing dal-GenE trial in individuals with a particular genetic profile. The randomized placebo-controlled REVEAL trial (Randomized Evaluation of the Effects of Anacetrapib through Lipid-Modification) demonstrated the clinical efficacy of the CETP inhibitor anacetrapib among patients with preexisting atherosclerotic vascular disease. In the present study, we examined the impact of ADCY9 genotype on response to anacetrapib in the REVEAL trial. Methods: Individuals with stable atherosclerotic vascular disease who were treated with intensive atorvastatin therapy received either anacetrapib 100 mg daily or matching placebo. Cox proportional hazards models, adjusted for the first 5 principal components of ancestry, were used to estimate the effects of allocation to anacetrapib on major vascular events (a composite of coronary death, myocardial infarction, coronary revascularization, or presumed ischemic stroke) and the interaction with ADCY9 rs1967309 genotype. Results: Among 19 210 genotyped individuals of European ancestry, 2504 (13.0%) had a first major vascular event during 4 years median follow-up: 1216 (12.6%) among anacetrapib-allocated participants and 1288 (13.4%) among placebo-allocated participants. Proportional reductions in the risk of major vascular events with anacetrapib did not differ significantly by ADCY9 genotype: hazard ratio (HR) = 0.92 (95% CI, 0.81–1.05) for GG; HR = 0.94 (95% CI, 0.84–1.06) for AG; and HR = 0.93 (95% CI, 0.76–1.13) for AA genotype carriers, respectively; genotypic P for interaction = 0.96. Furthermore, there were no associations between ADCY9 genotype and the proportional reductions in the separate components of major vascular events or meaningful differences in lipid response to anacetrapib. Conclusions: The REVEAL trial is the single largest study to date evaluating the ADCY9 pharmacogenetic interaction. It provides no support for the hypothesis that ADCY9 genotype is materially relevant to the clinical effects of the CETP inhibitor anacetrapib. The ongoing dal-GenE study will provide direct evidence as to whether there is any specific pharmacogenetic interaction with dalcetrapib. Clinical Trial Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01252953. URL: http://www.isrctn.com. Unique identifier: ISRCTN48678192. URL: https://www.clinicaltrialsregister.eu. Unique identifier: 2010-023467-18. [ABSTRACT FROM AUTHOR]

Cholesteryl ester transfer protein (CETP) inhibitor is a target for both lowering low-density lipoproteins and raising high-density lipoproteins. Anacetrapib was the lead compound in our cholesteryl ester transfer protein inhibitor program. Preclinical studies were initiated to support the safety of anacetrapib deposition in adipose tissue, followed by a clinical trial to evaluate the effects of anacetrapib in people with vascular disease. An ultra-high performance liquid chromatography/tandem mass spectrometry method was developed to determine tissue anacetrapib concentrations in the adipose of three animal species and humans. The assays were validated in the concentration ranges of 5-5000 ng/ml and 0.1-100 μg/ml. The anacetrapib concentrations in adipose tissue from preclinical and clinical studies were determined.

The REVEAL trial with anacetrapib, a CETP (cholesteryl ester transfer protein) inhibitor, has been one of the largest "lipid" studies conducted so far. Its aim was to confirm the hypothesis that an increase in high-density lipoprotein (HDL) cholesterol will reduce the cardiovascular risk. The CETP transporter glycoprotein transfers cholesterol esters and triglycerides from HDL to the liver and to atherogenic lipoproteins. The result is an increase in HDL cholesterol and a variable decrease in low-density lipoprotein (LDL) cholesterol. On the one hand, this effect is positive - i.e. a decreased concentration of cholesterol esters in atherogenic lipoproteins; on the other hand, there is a breaking of the cycle of cholesterol esters in the chain of macrophage-HDL-liver and VLDL/LDL. Previous studies with a number of other CETP inhibitors have failed to show a positive impact on the rates of atherothrombotic events or even demonstrated increased rates; therefore, the positive results of the secondary prevention REVEAL trial were surprising. The decrease in LDL cholesterol was high - in comparison with placebo, there was a documented decrease of more than 40% while the increase in HDL cholesterol was more than two-fold. The primary outcome measure, the rate of major coronary events, decreased statistically significantly - almost by a tenth. However, in absolute values, the decrease was small - only 1% for 4 years of treatment. The corresponding NNT (number needed to treat), i.e. the number of patients treated needed to prevent one bad outcome, was 400 patients a year. However, it needs to be emphasized that these were patients who had achieved optimal LDL cholesterol levels prior to treatment. Although the result of the trial was only of borderline significance from the clinical viewpoint, in terms of treatment strategy for dyslipidaemia the study has yielded a wealth of knowledge. First of all, it has shown that a decrease in LDL cholesterol is crucial. Given the fact that the study included patients with a mean baseline of 1.6 mmol/L under statin treatment, it has been shown that even a further decrease in LDL cholesterol is beneficial. Furthermore, it has been confirmed that increasing HDL cholesterol will not affect patient prognosis. In summary, the answer to the fundamental question "Is an increase in HDL cholesterol beneficial?" is negative. Nevertheless, the evidence that an LDL cholesterol decrease even below the strict target level of 1.6 mmol/L favourably affects atherothrombotic events is certainly beneficial. [ABSTRACT FROM AUTHOR]

Anacetrapib is a cholesteryl ester transfer protein inhibitor intended for the treatment of dyslipidemia. A phase 1 study was conducted to examine the pharmacokinetics and pharmacodynamics of multiple doses of anacetrapib in black compared to white healthy subjects. Although there was no apparent race‐related pharmacokinetic effect, attenuation of the lipid response was observed in black subjects. Specifically, high‐density lipoprotein cholesterol percentage increased 18.1% (absolute percentage points) less in black subjects (89.9%) when compared to increases in white subjects (108.0%). Similarly, the decrease in low‐density lipoprotein cholesterol was 17.8% (absolute percentage points) less in blacks (–21.2%) relative to whites (–39.0%). In contrast, there were no apparent race‐related differences in cholesteryl ester transfer protein mass or activity. Anacetrapib was generally well tolerated in this study. The results of this study suggest that there may be race‐related differences in pharmacodynamics of anacetrapib independent of pharmacokinetics. [ABSTRACT FROM AUTHOR]

Abstract The cholesteryl ester transfer protein (CETP) system moves cholesteryl esters (CE) from high density lipoproteins (HDL) to lower density lipoproteins, i.e. very low-density lipoprotein (VLDL) and low-density lipoprotein (LDL) in exchange for triglycerides (TGs). This shuttle process will ultimately form complexes facilitating a bidirectional exchange of CE and TGs, the end process being CE delivery to catabolic sites. The CETP system is generally characteristic of higher animal species; lower species, not provided with this system, have higher and enlarged HDL enriched with apo E, suitable for tissue receptor interaction. Discovery of the CETP system has led to the development of agents interfering with CETP, thus elevating HDL-C and potentially preventing cardiovascular (CV) disease. Activation of CETP leads instead to reduced HDL-C levels, but also to an enhanced removal of CE from tissues. CETP antagonists are mainly small molecules (torcetrapib, anacetrapib, evacetrapib, dalcetrapib) and have provided convincing evidence of a HDL-C raising activity, but disappointing results in trials of CV prevention. In contrast, the CETP agonist probucol leads to HDL-C lowering followed by an increment of tissue cholesterol removal (reduction of xanthomas, xanthelasmas) and positive findings in secondary prevention trials. The drug has an impressive anti-inflammatory profile (markedly reduced interleukin-1β expression). Newer agents, some of natural origin, have additional valuable pharmacodynamic properties. The pharmacological approach to the CETP system remains enigmatic, although the failure of CETP antagonists has dampened enthusiasm. Studies on the system, a crossroad for any investigation on cholesterol metabolism, have however provided crucial contributions and will still be confronting any scientist working on CV prevention. Highlights • The CETP system transfers-exchanges cholesteryl esters for triglycerides from HDL to VLDL-LDL. • Changes of the system may lead to either higher or lower HDL-cholesterol levels. • Blockade of CETP leads to higher HDL-cholesterol but disappointing cardiovascular protection. • Activation of CETP leads to lower HDL-cholesterol but may result in arterial benefit. • Choice between agonism and antagonism to CETP is presently an object of debate. [ABSTRACT FROM AUTHOR]

Therapeutic interventions aimed at increasing high-density lipoprotein (HDL) levels in order to reduce the residual cardiovascular (CV) risk of optimally drug treated patients have not provided convincing results, so far. Transfer of cholesterol from extrahepatic tissues to the liver appears to be the major atheroprotective function of HDL, and an elevation of HDL levels could represent an effective strategy. Inhibition of the cholesteryl ester transfer protein (CETP), raising HDL-cholesterol (HDL-C) and apolipoprotein A-I (apoA-I) levels, reduces low-density lipoprotein-cholesterol (LDL-C) and apoB levels, thus offering a promising approach. Despite the beneficial influence on cholesterol metabolism, off-target effects and lack of reduction in CV events and mortality (with torcetrapib, dalcetrapib and evacetrapib) highlighted the complex mechanism of CETP inhibition. After the failure of the above mentioned inhibitors in phase III clinical development, possibly due to the short duration of the trials masking benefit, the secondary prevention REVEAL trial has recently shown that the inhibitor anacetrapib significantly raised HDL-C (+104%), reduced LDL-C (−18%), with a protective effect on major coronary events (RR, 0.91; 95%CI, 0.85–0.97; p = 0.004). Whether LDL-C lowering fully accounts for the CV benefit or if HDL-C-rise is a crucial factor still needs to be determined, although the reduction of non-HDL (−18%) and Lp(a) (−25%), should be also taken into account. In spite of the positive results of the REVEAL Study, Merck decided not to proceed in asking regulatory approval for anacetrapib. Dalcetrapib (Dal-GenE study) and CKD-519 remain the two molecules within this area still in clinical development. [ABSTRACT FROM AUTHOR]

Abstract: Anacetrapib is a cholesteryl ester transfer protein (CETP) inhibitor being developed for the treatment of mixed dyslipidemia. The aim of the study was to evaluate the pharmacokinetic, pharmacodynamic, and safety characteristics of anacetrapib following single doses in healthy, young Japanese men. In a double‐blind, randomized, placebo‐controlled, 3‐panel, single‐rising‐dose study, 6 healthy young Japanese male or white male subjects (aged 19 to 44 years) received single oral doses of 5 to 500 mg anacetrapib, and 2 received placebo. Plasma and urine drug concentrations were measured 0–168 hours postdose, and plasma CETP inhibition was measured 0–24 hours postdose. Urinary anacetrapib levels were all below quantitation limits. Plasma concentrations of anacetrapib increased approximately less than dose‐proportionally. Consumption of a traditional Japanese breakfast prior to dosing increased the plasma pharmacokinetics of anacetrapib in Japanese subjects compared with fasted conditions, to a similar extent as in white subjects. CETP activity measured over 0–24 hours postdose resulted in significant inhibition. Anacetrapib was generally well tolerated, and there were no serious adverse experiences. No clinically meaningful differences in PK and CETP inhibition parameters were found between Japanese and white subjects. [ABSTRACT FROM AUTHOR]

Background: Cardiovascular disease (CVD) is the major cause of morbidity and mortality worldwide. Anacetrapib may be a new treatment option that has a cardiovascular benefit for the management of dyslipidemia. Objective: The aim of our current study was to perform a systematic review and meta-analysis of all randomized controlled trials (RCTs) assessing the effect and safety of anacetrapib in the treatment of dyslipidemia. Methods: We systematically searched PubMed, Embase, and Cochrane Library database from their inception to 5 October 2017, with the terms: ‘anacetrapib’ and ‘placebo’. From 287 initial citations, 10 studies including 34781 patients with dyslipidemia were included in the final systematic review and meta-analysis. Results: Pooled results showed that anacetrapib significantly increased high density lipoprotein cholesterol (HDL-C) [weighted mean differences (WMD) 53.07, 95% confidence interval (95% CI) 46.79 to 59.36] and apolipoprotein AI (ApoAI) (WMD 53.44, 95% CI 45.72 to 61.16). Our study also showed that anacetrapib significantly reduced low density lipoprotein cholesterol (LDL-C) (WMD −32.99; 95% CI −37.13 to −28.86), Non-HDL-C (WMD −39.19; 95% CI −52.22 to −26.16), triglycerides (TG) (WMD −9.97; 95% CI −10.54 to −9.41), apolipoprotein B (ApoB) (WMD −22.55; 95% CI −28.56 to −16.54) and lipoprotein a [LP(a)] (WMD −13.35; 95% CI −18.31 to −8.39). Our results demonstrated that there was no significant difference in all the following adverse events between the anacetrapib group and placebo group: [hepato-toxicity (OR 0.90, 95% CI: 0.75 to 1.07); musculoskeletal injury (OR 1.01, 95% CI: 0.88 to 1.15); drug-related adverse event (OR 1.00, 95% CI: 0.96 to 1.05); drug-related withdrawn (OR 1.01, 95% CI: 0.95 to 1.08)]. Conclusions: Although further studies are needed, our findings clearly offer support to the use of anacetrapib in the clinical management of patients with dyslipidemia. [ABSTRACT FROM PUBLISHER]

Cholesteryl ester transfer protein (CETP) facilitates movement of esterified cholesterol between high-density lipoproteins (HDLs) and apolipoprotein B-containing lipoproteins. By virtue of their ability to raise HDL cholesterol and lower low-density lipoprotein cholesterol, pharmacological inhibitors of CETP have received considerable attention as potential new agents in cardiovascular prevention. While early studies of CETP inhibitors have demonstrated a lack of clinical efficacy and potential toxicity, development of the potent CETP inhibitor, anacetrapib, has moved forward, with emerging evidence suggesting a role in reducing cardiovascular events. The experience with anacetrapib and its potential for use in clinical practice are reviewed here. [ABSTRACT FROM AUTHOR]

Introduction: Even though statins represent the mainstay of treatment of heterozygous familial hypercholesterolemia (FH), their low-density lipoprotein cholesterol (LDL-C) lowering efficacy is finite and most patients with FH will not achieve LDL-C targets with statin monotherapy. Addition of ezetimibe with or without bile acid sequestrants will also not lead to treatment goals in many of these patients, particularly in those with established cardiovascular disease. In this selected subgroup of the FH population, proprotein convertase subtilisin-kexin type 9 (PCSK9) inhibitors provide substantial reductions in LDL-C levels, reduce cardiovascular morbidity and appear to be safe. Mipomersen, an antisense single-strand oligonucleotide that inhibits the production of apoB by binding to the mRNA that encodes the synthesis of apoB, and lomitapide, an inhibitor of microsomal triglyceride transfer protein, also reduce LDL-C levels but are currently indicated only for the management of homozygous FH. Areas covered: In the present review, the role of PCSK9 inhibitors, mipomersen and lomitapide in the management of FH is briefly discussed. Other LDL-C-lowering agents under evaluation include inclisiran, a small interference RNA molecule that induces long-term inhibition of PSCK9 synthesis, anacetrapib, a cholesterol ester-transfer protein inhibitor, ETC-1002 (bempedoic acid), an inhibitor of adenosine triphosphate citrate lyase, and gemcabene, which reduces hepatic apolipoprotein C-III mRNA. The safety and efficacy of these agents are also reviewed. Expert Commentary: Even though several novel treatment options for heterozygous FH are under development, it remains to be shown whether these treatments will also reduce cardiovascular morbidity in these high-risk patients. [ABSTRACT FROM PUBLISHER]

Cholesteryl ester transfer protein (CETP) inhibitors significantly increase serum high-density lipoprotein cholesterol (HDL) cholesterol levels and decrease low-density lipoprotein cholesterol (LDL) cholesterol concentration. However, three drugs of this class failed to show a decrease of cardiovascular events in high-risk patients. A new CETP inhibitor, anacetrapib, substantially increases HDL cholesterol and apolipoprotein (Apo) AI levels with a profound increase of large HDL2 particles, but also pre-β HDL particles, decreases LDL cholesterol levels mainly due to increased catabolism of LDL particles through LDL receptors, decreases lipoprotein a (Lp(a)) levels owing to a decreased Apo (a) production and, finally, decreases modestly triglyceride (TRG) levels due to increased lipolysis and increased receptor-mediated catabolism of TRG-rich particles. Interestingly, anacetrapib may be associated with a beneficial effect on carbohydrate homeostasis. Furthermore, the Randomized EValuation of the Effects of Anacetrapib Through Lipid-modification (REVEAL) trial showed that anacetrapib administration on top of statin treatment significantly reduces cardiovascular events in patients with atherosclerotic vascular disease without any significant increase of adverse events despite its long half-life. Thus, anacetrapib could be useful for the effective management of dyslipidemias in high-risk patients that do not attain their LDL cholesterol target or are statin intolerable, while its role in patients with increased Lp(a) levels remains to be established. [ABSTRACT FROM AUTHOR]

Tubular lipid binding proteins (TULIPs) have become a focus of interest in the cell biology of lipid signalling, lipid traffic and membrane contact sites. Each tubular domain has an internal pocket with a hydrophobic lining that can bind a hydrophobic molecule such as a lipid. This allows TULIP proteins to carry lipids through the aqueous phase. TULIP domains were first found in a large family of extracellular proteins related to the bacterial permeability-inducing protein (BPI) and cholesterol ester transfer protein (CETP). Since then, the same fold and lipid transfer capacity have been found in SMP domains (so-called for their occurrence in synaptotagmin, mitochondrial and lipid binding proteins), which localise to intracellular membrane contact sites. Here the methods for identifying known TULIPs are described, and used to find previously unreported TULIPs, one in the silk polymer and another in prokaryotes illustrated by the E. coli protein YceB. The bacterial TULIP alters views on the likely evolution of the domain, suggesting its presence in the last universal common ancestor. The major function of TULIPs is to handle lipids, but we still do not know how they work in detail, or how many more remain to be discovered. This article is part of a Special Issue entitled: Membrane Contact Sites edited by Christian Ungermann and Benoit Kornmann. [ABSTRACT FROM AUTHOR]

Background and aims We aimed to assess the effects of cholesteryl ester transfer protein inhibitor anacetrapib added to statin ± other lipid-modifying therapies (LMT) in Japanese patients with dyslipidemia who were not at their LDL-C goal. Methods Patients on a stable dose of statin ± other LMT with LDL-C ≥100 mg/dL to <145 mg/dL, ≥120 mg/dL to <165 mg/dL, ≥140 mg/dL or ≥160 mg/dL for patients with a history of coronary heart disease (CHD), high-, moderate- and low-risk patients respectively, were randomized 2:1, stratified by background therapy, to double-blind anacetrapib 100 mg (n = 204) or placebo (n = 103) for 24 weeks, followed by a 28-week open-label extension phase (anacetrapib 100 mg) and a 12-week off-drug safety follow-up phase. The primary endpoint was percent change from baseline in LDL-C (beta-quantification method), as well as the safety profile of anacetrapib at Week 24; HDL-C was a key secondary endpoint. Results Anacetrapib 100 mg further reduced LDL-C (38.0%), non-HDL-C (35.1%), ApoB (28.7%), and Lp(a) (48.3%) and increased HDL-C (148.9%) and ApoAI (50.7%) versus placebo ( p < 0.001 for all). There were no meaningful differences between the groups in the proportion of patients with liver enzymes elevations (2.0% vs. 0%), creatine kinase elevations overall (0.5% vs. 0%) or with muscle symptoms (0.5% vs. 0%), blood pressure, electrolytes or adjudicated cardiovascular events (0.5% vs. 0%). In the open–label period, sustained effects on lipid parameters were observed with anacetrapib and the treatment was generally well tolerated. Conclusions Long-term treatment with anacetrapib 100 mg substantially reduced LDL-C, increased HDL-C and was well tolerated in Japanese patients with dyslipidemia (ClinicalTrials.gov number NCT01760460). [ABSTRACT FROM AUTHOR]

Cholesteryl ester transfer protein (CETP) transfers cholesteryl ester and triglyceride between HDL and apoB-containing lipoproteins. Anacetrapib (ANA), a reversible inhibitor of CETP, raises HDL cholesterol and lowers LDL cholesterol in dyslipidemic patients. We previously demonstrated that ANA increases macrophage-to-feces reverse cholesterol transport and fecal cholesterol excretion in hamsters, and increased preβ HDL-dependent cholesterol efflux via ABCA1 in vitro. However, the effects of ANA on in vivo preβ HDL have not been characterized. In vitro, ANA inhibited the formation of preβ, however in ANA-treated dyslipidemic hamsters, preβ HDL levels (measured by two-dimensional gel electrophoresis) were increased, in contrast to in vitro findings. Because changes in plasma preβ HDL have been proposed to potentially affect markers of cholesterol absorption with other CETP inhibitors, a dual stable isotope method was used to directly measure cholesterol absorption in hamsters. ANA treatment of hamsters (on either dyslipidemic or normal diet) had no effect on cholesterol absorption, while dalcetrapib-treated hamsters displayed an increase in cholesterol absorption. Taken together, these data support the notion that ANA promotes preβ HDL functionality in vivo, with no effects on cholesterol absorption.

The mechanism by which cholesteryl ester transfer protein (CETP) activity affects HDL metabolism was investigated using agents that selectively target CETP (dalcetrapib, torcetrapib, anacetrapib). In contrast with torcetrapib and anacetrapib, dalcetrapib requires cysteine 13 to decrease CETP activity, measured as transfer of cholesteryl ester (CE) from HDL to LDL, and does not affect transfer of CE from HDL3 to HDL2. Only dalcetrapib induced a conformational change in CETP, when added to human plasma in vitro, also observed in vivo and correlated with CETP activity. CETP-induced pre-β-HDL formation in vitro in human plasma was unchanged by dalcetrapib ≤3 µM and increased at 10 µM. A dose-dependent inhibition of pre-β-HDL formation by torcetrapib and anacetrapib (0.1 to 10 µM) suggested that dalcetrapib modulates CETP activity. In hamsters injected with [3H]cholesterol-labeled autologous macrophages, and given dalcetrapib (100 mg twice daily), torcetrapib [30 mg once daily (QD)], or anacetrapib (30 mg QD), only dalcetrapib significantly increased fecal elimination of both [3H]neutral sterols and [3H]bile acids, whereas all compounds increased plasma HDL-[3H]cholesterol. These data suggest that modulation of CETP activity by dalcetrapib does not inhibit CETP-induced pre-β-HDL formation, which may be required to increase reverse cholesterol transport.

Cholesteryl ester transfer protein (CETP) has been identified as a novel target for increasing HDL cholesterol levels. In this report, we describe the biochemical characterization of anacetrapib, a potent inhibitor of CETP. To better understand the mechanism by which anacetrapib inhibits CETP activity, its biochemical properties were compared with CETP inhibitors from distinct structural classes, including torcetrapib and dalcetrapib. Anacetrapib and torcetrapib inhibited CETP-mediated cholesteryl ester and triglyceride transfer with similar potencies, whereas dalcetrapib was a significantly less potent inhibitor. Inhibition of CETP by both anacetrapib and torcetrapib was not time dependent, whereas the potency of dalcetrapib significantly increased with extended preincubation. Anacetrapib, torcetrapib, and dalcetrapib compete with one another for binding CETP; however anacetrapib binds reversibly and dalcetrapib covalently to CETP. In addition, dalcetrapib was found to covalently label both human and mouse plasma proteins. Each CETP inhibitor induced tight binding of CETP to HDL, indicating that these inhibitors promote the formation of a complex between CETP and HDL, resulting in inhibition of CETP activity.

Anacetrapib is a potent and selective CETP inhibitor and is undergoing phase III clinical trials for the treatment of dyslipidemia. A simple and sensitive high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method for the quantification of anacetrapib in rat plasma was developed and validated using an easily purchasable compound, chlorpropamide, as an internal standard (IS). A minimal volume of rat plasma sample (20 μL) was prepared by a single-step deproteinization procedure with 80 μL of acetonitrile. Chromatographic separation was performed using Kinetex C18 column with a gradient mobile phase consisting of water and acetonitrile containing 0.1% formic acid at a flow rate of 0.3 mL/min. Mass spectrometric detection was performed using selected reaction monitoring modes at the mass/charge transitions m/z 638 → 283 for anacetrapib and m/z 277 → 175 for IS. The assay was validated to demonstrate the selectivity, linearity, precision, accuracy, recovery, matrix effect and stability. The lower limit of quantification was 5 ng/mL. This LC-MS/MS assay was successfully applied in the rat plasma protein binding and pharmacokinetic studies of anacetrapib. The fraction of unbound anacetrapib was determined to be low (ranging from 5.66 to 12.3%), and the absolute oral bioavailability of anacetrapib was 32.7%. [ABSTRACT FROM AUTHOR]

Purpose of Review: Elevated plasma concentrations of lipoprotein(a) (Lp(a)) are an independent and causal risk factor for cardiovascular diseases including coronary artery disease, ischemic stroke, and calcific aortic valve stenosis. This review summarizes the rationale for Lp(a) lowering and surveys relevant clinical trial data using a variety of agents capable of lowering Lp(a). Recent Findings: Contemporary guidelines and recommendations outline populations of patients who should be screened for elevated Lp(a) and who might benefit from Lp(a) lowering. Therapies including drugs and apheresis have been described that lower Lp(a) levels modestly (∼20 %) to dramatically (∼80 %). Existing therapies that lower Lp(a) also have beneficial effects on other aspects of the lipid profile, with the exception of Lp(a)-specific apheresis and an antisense oligonucleotide that targets the mRNA encoding apolipoprotein(a). Summary: No clinical trials conducted to date have managed to answer the key question of whether Lp(a) lowering confers a benefit in terms of ameliorating cardiovascular risk, although additional outcome trials of therapies that lower Lp(a) are ongoing. It is more likely, however, that Lp(a)-specific agents will provide the most appropriate approach for addressing this question. [ABSTRACT FROM AUTHOR]

Introduction: Cholesteryl ester transfer protein (CETP) inhibitors substantially increase the concentration of high-density lipoprotein cholesterol (HDL-C), which may have a possible beneficial effect for cardiovascular disease risk reduction.Areas Covered: Current data regarding the effects of CETP inhibitors on cardiovascular disease risk and possible mechanisms for their effects and safety are presented in this review. Expert commentary: The first CETP inhibitor, torcetrapib, was discontinued because of increased off-target adverse effects (increased serum aldosterone and blood pressure levels). The development program of dalcetrapib and evacetrapib, which were not associated with increased blood pressure, was terminated due to futility (insufficient efficacy) concerning cardiovascular outcomes. Although the failure of torcetrapib has been attributed to specific off-target effects, there are some common characteristics between CETP inhibitors pointing to the possibility that certain adverse effects may be class-specific. The newer CETP inhibitors anacetrapib and TA-8995 have promising effects on lipid profile and metabolism (increase of HDL-C and reduction of both low-density lipoprotein cholesterol and lipoprotein (a) levels), but their cardiovascular effects and safety profile have not yet been confirmed in large outcome trials. [ABSTRACT FROM AUTHOR]

Background and aims This multicenter, randomized, double-blind, placebo-controlled study assessed the lipid-modifying efficacy/safety profile of anacetrapib 100 mg added to ongoing statin ± other lipid-modifying therapies (LMT) in Japanese patients with heterozygous familial hypercholesterolemia (HeFH). Methods Patients 18–80 years with a genotype-confirmed/clinical diagnosis of HeFH who were on a stable dose of statin ± other LMT for ≥6 weeks and with an LDL-C concentration ≥100 mg/dL were randomized to anacetrapib 100 mg (n = 34) or placebo (n = 34) for 12 weeks, followed by a 12-week off-drug reversal phase. The primary endpoints were percent change from baseline in LDL-C (beta-quantification method [BQ]) and safety/tolerability. Results At Week 12, treatment with anacetrapib reduced LDL-C (BQ) compared to placebo and resulting in a between-group difference of 29.8% (95% CI: −38.6 to −21.0; p < 0.001) favoring anacetrapib. Anacetrapib also reduced non-HDL-C (23. 6%; p < 0.001), ApoB (14.1%; p < 0.001) and Lp(a) (48.7%; p < 0.001), and increased HDL-C (110.0%; p < 0.001) and ApoA1 (48.2%; p < 0.001) versus placebo. Anacetrapib 100 mg added to ongoing therapy with statin ± other LMT for 12 weeks was generally well-tolerated. There were no differences between the groups in the proportion of patients who discontinued drug due to an adverse event or abnormalities in liver enzymes, creatinine kinase, blood pressure, electrolytes or adjudicated cardiovascular events. Conclusions In Japanese patients with HeFH, treatment with anacetrapib 100 mg for 12 weeks resulted in substantial reductions in LDL-C and increases in HDL-C and was well tolerated. ( ClinicalTrials.gov NCT01824238 ) [ABSTRACT FROM AUTHOR]