rvx-208 and Atherosclerosis

RVX-208 is a first-in-class, orally active, novel small molecule in development by Resverlogix Corporation (Calgary, AB, Canada). It acts through an epigenetic mechanism by inhibiting the bromodomain and extraterminal (BET) family of proteins, increasing apolipoprotein A-I (apoA-I) and targeting high-density lipoprotein (HDL) metabolism, including generating of nascent HDL and increased larger HDL particles, resulting in the stimulation of reverse cholesterol transport. RVX-208 also has a beneficial effect on inflammatory factors known to be involved in atherosclerosis and plaque stability. New therapeutic strategies are needed for patients with atherosclerosis.. In this review, the authors evaluate the use of RVX-208 as an agent for the treatment of atherosclerosis. The article is based on a literature search considering both animal and human studies available on PubMed as well as Media Releases from the Resverlogix Corporation.. The current evidence suggests promising beneficial effects of this novel drug in the prevention and treatment of atherosclerosis and other metabolic disorders. Its unique mechanism of action is encouraging; it affects several pathways and has a modest effect on HDL levels. There is also a shift in particle size to larger HDL particles, which may have potent atheroprotective effects. Future clinical development is needed, including safety assessment.

Topics: Animals; Atherosclerosis; Cholesterol, HDL; Epigenesis, Genetic; Humans; Metabolic Diseases; Plaque, Atherosclerotic; Quinazolines; Quinazolinones

How to manage residual atherosclerosis risk after the statin therapy is a major concern in cardiovascular medicine. In addition to life-style modifications, new drugs against atherosclerotic and inflammatory vascular diseases are expected. In current clinical trials, phospholipase A2 inhibitors(darapladib, varespladib), RVX-208, D-4F, CETP inhibitors (anacetrapib, dalcetrapib), succinobucol are investigated. Some has been failed, but others are still promising. On molecular target basis of PAF-AH, CETP, PON, ABC transporters of A1 and G1, SR-BI, HO-1, potential benefits and side effects are discussed.

Topics: Acetates; Amides; Apolipoprotein A-I; Atherosclerosis; Benzaldehydes; Blood Proteins; Cholesterol Ester Transfer Proteins; Clinical Trials as Topic; Drug Design; Esters; Humans; Indoles; Keto Acids; Molecular Targeted Therapy; Oxazolidinones; Oximes; Probucol; Quinazolines; Quinazolinones; Sulfhydryl Compounds

RVX 208 (RVX-208; RVX000222) is a first-in-class novel small molecule in development by Resverlogix Corporation for acute coronary syndromes, atherosclerosis and Alzheimer disease. It increases the levels of apolipoprotein A1 and high-density lipoprotein cholesterol, thereby potentially reducing the risk for cardiovascular disease. This review discusses the key development milestones and therapeutic trials of this drug. This summary has been extracted from Wolters Kluwer's R&D Insight drug pipeline database. R&D Insight tracks and evaluates drug development worldwide through the entire development process, from discovery, through pre-clinical and clinical studies to market launch. This is an open access article published under the terms of the Creative Commons License "Attribution-NonCommercial-NoDerivative 3.0" (http://creativecommons.org/licenses/by-nc-nd/3.0/) which permits non-commercial use, distribution, and reproduction, provided the original work is properly cited and not altered.

Topics: Acute Coronary Syndrome; Alzheimer Disease; Animals; Atherosclerosis; Clinical Trials as Topic; Drug Evaluation, Preclinical; Humans; Quinazolines; Quinazolinones

Apabetalone is a selective bromodomain and extra-terminal (BET) inhibitor which modulates lipid and inflammatory pathways implicated in atherosclerosis. The impact of apabetalone on attenuated coronary atherosclerotic plaque (AP), a measure of vulnerability, is unknown.. The ApoA-1 Synthesis Stimulation and intravascular Ultrasound for coronary atheroma Regression Evaluation (ASSURE; NCT01067820) study employed serial intravascular ultrasound (IVUS) measures of coronary atheroma in 281 patients treated with apabetalone or placebo for 26 weeks. AP was measured at baseline and follow-up. Factors associated with changes in AP were investigated.. AP was observed in 31 patients (11%) [27 (13.0%) in the apabetalone group and four (5.5%) in the placebo group]. The apabetalone group demonstrated reductions in AP length by - 1 mm [interquartile range (IQR) - 4, 1] (p = 0.03), AP arc by - 37.0° (IQR - 59.2, 8.2) (p = 0.003) and the AP index by - 34.6 mm° (IQR - 52.6, 10.1) (p = 0.003) from baseline. The change in AP index correlated with on-treatment concentration of high-density lipoprotein (HDL) particles (r = - 0.52, p = 0.006), but not HDL cholesterol (r = - 0.11, p = 0.60) or apolipoprotein A-1 (r = - 0.16, p = 0.43). Multivariable analysis revealed that on-treatment concentrations of HDL particles (p = 0.03) and very low-density lipoprotein particles (p = 0.01) were independently associated with changes in AP index.. Apabetalone favorably modulated ultrasonic measures of plaque vulnerability in the population studied, which may relate to an increase in HDL particle concentrations. The clinical implications are currently being investigated in the phase 3 major adverse cardiac event outcomes trial BETonMACE.

Topics: Aged; Apolipoprotein A-I; Atherosclerosis; Cholesterol, HDL; Coronary Angiography; Coronary Artery Disease; Double-Blind Method; Female; Heart; Humans; Male; Middle Aged; Plaque, Atherosclerotic; Prospective Studies; Quinazolinones

NF-κB signaling is a key regulator of inflammation and atherosclerosis. NF-κB cooperates with bromodomain-containing protein 4 (BRD4), a transcriptional and epigenetic regulator, in endothelial inflammation. This study aimed to investigate whether BRD4 inhibition would prevent the proinflammatory response towards TNF-α in endothelial cells. We used TNF-α treatment of human umbilical cord-derived vascular endothelial cells to create an in vitro inflammatory model system. Two small molecule inhibitors of BRD4-namely, RVX208 (Apabetalone), which is in clinical trials for the treatment of atherosclerosis, and JQ1-were used to analyze the effect of BRD4 inhibition on endothelial inflammation and barrier integrity. BRD4 inhibition reduced the expression of proinflammatory markers such as

Topics: Atherosclerosis; Cell Cycle Proteins; Endothelial Cells; Humans; Inflammation; Midkine; NF-kappa B; Nuclear Proteins; Transcription Factors; Tumor Necrosis Factor-alpha

Patients with cardiovascular disease (CVD) and type 2 diabetes (DM2) have a high residual risk for experiencing a major adverse cardiac event. Dysregulation of epigenetic mechanisms of gene transcription in innate immune cells contributes to CVD development but is currently not targeted by therapies. Apabetalone (RVX-208) is a small molecule inhibitor of bromodomain and extra-terminal (BET) proteins-histone acetylation readers that drive pro-inflammatory and pro-atherosclerotic gene transcription. Here, we assess the impact of apabetalone on ex vivo inflammatory responses of monocytes from DM2 + CVD patients.. Monocytes isolated from DM2 + CVD patients and matched controls were treated ex vivo with apabetalone, interferon γ (IFNγ), IFNγ + apabetalone or vehicle and phenotyped for gene expression and protein secretion. Unstimulated DM2 + CVD monocytes had higher baseline IL-1α, IL-1β and IL-8 cytokine gene expression and Toll-like receptor (TLR) 2 surface abundance than control monocytes, indicating pro-inflammatory activation. Further, DM2 + CVD monocytes were hyper-responsive to stimulation with IFNγ, upregulating genes within cytokine and NF-κB pathways > 30% more than control monocytes (p < 0.05). Ex vivo apabetalone treatment countered cytokine secretion by DM2 + CVD monocytes at baseline (GROα and IL-8) and during IFNγ stimulation (IL-1β and TNFα). Apabetalone abolished pro-inflammatory hyper-activation by reducing TLR and cytokine gene signatures more robustly in DM2 + CVD versus control monocytes.. Monocytes isolated from DM2 + CVD patients receiving standard of care therapies are in a hyper-inflammatory state and hyperactive upon IFNγ stimulation. Apabetalone treatment diminishes this pro-inflammatory phenotype, providing mechanistic insight into how BET protein inhibition may reduce CVD risk in DM2 patients.

Topics: Aged; Atherosclerosis; Cardiovascular Diseases; Case-Control Studies; Cytokines; Diabetes Mellitus, Type 2; DNA Methylation; Epigenesis, Genetic; Female; Humans; Inflammation; Interleukin-18; Male; Middle Aged; Monocytes; Phenotype; Proteins; Quinazolinones; Toll-Like Receptor 2; Transcription Factors

High density lipoproteins (HDL), through activity of the main protein component apolipoprotein A-I (ApoA-I), can reduce the risk of cardiovascular disease (CVD) by removing excess cholesterol from atherosclerotic plaque. In this study, we demonstrate that the bromodomain and extraterminal domain (BET) inhibitor RVX-208 increases ApoA-I gene transcription and protein production in human and primate primary hepatocytes. Accordingly, RVX-208 also significantly increases levels of ApoA-I, HDL-associated cholesterol, and HDL particle number in patients who received the compound in recently completed phase 2b trials SUSTAIN and ASSURE. Moreover, a post-hoc analysis showed lower instances of major adverse cardiac events in patients receiving RVX-208. To understand the effects of RVX-208 on biological processes underlying cardiovascular risk, we performed microarray analyses of human primary hepatocytes and whole blood treated ex vivo. Overall, data showed that RVX-208 raises ApoA-I/HDL and represses pro-inflammatory, pro-atherosclerotic and pro-thrombotic pathways that can contribute to CVD risk.

Topics: Apolipoprotein A-I; Atherosclerosis; Cardiovascular Diseases; Cells, Cultured; Cholesterol, HDL; Clinical Trials, Phase II as Topic; Dose-Response Relationship, Drug; Gene Expression Profiling; Hepatocytes; Humans; Hypolipidemic Agents; Liver; Male; Oligonucleotide Array Sequence Analysis; Quinazolines; Quinazolinones; Randomized Controlled Trials as Topic; Retrospective Studies; Signal Transduction; Time Factors; Up-Regulation

Despite the benefit of statins in reducing cardiovascular risk, a sizable proportion of patients still remain at risk. Since HDL reduces CVD risk through a process that involves formation of pre-beta particles that facilitates the removal of cholesterol from the lipid-laden macrophages in the arteries, inducing pre-beta particles, may reduce the risk of CVD. A novel BET bromodomain antagonist, RVX-208, was reported to raise apoA-I and increase preβ-HDL particles in non-human primates and humans. In the present study, we investigated the effect of RVX-208 on aortic lesion formation in hyperlipidemic apoE(-/-) mice. Oral treatments of apoE(-/-) mice with 150 mg/kg b.i.d RVX-208 for 12 weeks significantly reduced aortic lesion formation, accompanied by 2-fold increases in the levels of circulating HDL-C, and ∼50% decreases in LDL-C, although no significant changes in plasma apoA-I were observed. Circulating adhesion molecules as well as cytokines also showed significant reduction. Haptoglobin, a proinflammatory protein, known to bind with HDL/apoA-I, decreased >2.5-fold in the RVX-208 treated group. With a therapeutic dosing regimen in which mice were fed Western diet for 10 weeks to develop lesions followed by switching to a low fat diet and concurrent treatment with RVX-208 for 14 weeks, RVX-208 similarly reduced lesion formation by 39% in the whole aorta without significant changes in the plasma lipid parameters. RVX-208 significantly reduced the proinflammatory cytokines IP-10, MIP1(®) and MDC. These results show that the antiatherogenic activity of BET inhibitor, RVX-208, occurs via a combination of lipid changes and anti-inflammatory activities.

Topics: Animals; Aorta; Aortic Diseases; Apolipoprotein A-I; Apolipoproteins E; Atherosclerosis; Betaine-Homocysteine S-Methyltransferase; Cell Line; Cholesterol, HDL; Cholesterol, LDL; Cytokines; Diet, Fat-Restricted; Diet, Western; Drug Evaluation, Preclinical; Endothelial Cells; Gene Expression Profiling; Humans; Hyperlipidemias; Inflammation; Liver; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Quinazolines; Quinazolinones; RNA, Messenger; U937 Cells

Increased synthesis of Apolipoprotein A-I (ApoA-I) and HDL is believed to provide a new approach to treating atherosclerosis through the stimulation of reverse cholesterol transport. RVX-208 increases the production of ApoA-I in hepatocytes in vitro, and in vivo in monkeys and humans, which results in increased HDL-C, but the molecular target was not previously reported. Using binding assays and X-ray crystallography, we now show that RVX-208 selectively binds to bromodomains of the BET (Bromodomain and Extra Terminal) family, competing for a site bound by the endogenous ligand, acetylated lysine, and that this accounts for its pharmacological activity. siRNA experiments further suggest that induction of ApoA-I mRNA is mediated by BET family member BRD4. These data indicate that RVX-208 increases ApoA-I production through an epigenetic mechanism and suggests that BET inhibition may be a promising new approach to the treatment of atherosclerosis.

Topics: Animals; Apolipoprotein A-I; Atherosclerosis; Binding Sites; Cell Cycle Proteins; Cell Line; Crystallography, X-Ray; Epigenesis, Genetic; Hepatocytes; Humans; Models, Molecular; Nuclear Proteins; Protein Conformation; Protein Serine-Threonine Kinases; Quinazolines; Quinazolinones; Recombinant Proteins; RNA, Small Interfering; Transcription Factors