Potential effects of icosapent ethyl on cardiovascular outcomes in cigarette smokers: REDUCE-IT smoking

Management of dyslipidaemia in patients with comorbidities-facing the challenge

This review aims to examine the evidence on the benefits and risks of lipid-lowering drugs in patients with liver disease. Elevated liver enzyme levels often lead to cautious discontinuation of these drugs, potentially withholding from patients their benefit in reducing cardiovascular disease morbidity and mortality. Using a literature search of PubMed, we examine the efficacy and safety profiles of various lipid-lowering agents, including statins, ezetimibe, bempedoic acid, PCSK9 inhibitors, fibrates, and icosapent ethyl, focusing particularly on their potential side effects related to liver health. A major challenge in the assessment of drug-induced hepatotoxicity is the fact that it relies heavily on case reports rather than real-world evidence. There is currently a lack of robust evidence on lipid-lowering therapy in people with pre-existing liver disease. Nevertheless, we have attempted to summarize the available data for all the drugs mentioned in order to provide guidance for the treatment of patients with liver dysfunction. This review highlights the need for further research to optimize treatment strategies for patients with coexisting liver and cardiovascular disease.

Effects of icosapent ethyl according to baseline residual risk in patients with atherosclerotic cardiovascular disease: results from REDUCE-IT

AIMS

Icosapent ethyl lowers triglycerides and significantly reduces major adverse cardiovascular events (MACE), though treatment effects may vary between individuals. This study aimed to determine the relative and absolute effects of icosapent ethyl on MACE according to baseline cardiovascular disease (CVD) risk in patients with atherosclerotic cardiovascular disease (ASCVD).

METHODS AND RESULTS

Participants from the Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial (REDUCE-IT) with ASCVD were included (n = 5785). The primary outcome was 3-point MACE, i.e. non-fatal myocardial infarction, non-fatal stroke, or cardiovascular death. Baseline 5-year risk of MACE was estimated using the European Society of Cardiology (ESC) guideline-recommended SMART2 risk score. Modification of the relative treatment effects of icosapent ethyl by baseline risk was assessed using Cox proportional hazards models, including a treatment-by-risk interaction. Next, treatment effects were assessed stratified by quartiles of baseline risk. During a median follow-up of 4.8 years (interquartile range 3.2-5.3), MACE occurred in 361 vs. 489 patients in the icosapent ethyl vs. placebo group [95% confidence interval (CI)]; hazard ratio (HR) 0.72 (0.63-0.82), absolute risk reduction (ARR) 4.4% (2.6-6.2%), number needed to treat (NNT) 23 (16-38), and 5-year Kaplan-Meier estimated cumulative incidence reduction (CIR) 5.7% (3.5-7.9%). Icosapent ethyl significantly reduced MACE in all risk quartiles, with an HR (95% CI) of 0.62 (0.43-0.88), 0.66 (0.48-0.92), 0.69 (0.53-0.90), and 0.78 (0.63-0.96), respectively (P for treatment-by-risk interaction = 0.106). The ARR (95% CI) increased across risk quartiles, i.e. was 3.9% (1.0-6.8%), 4.3% (1.2-7.3%), 5.1% (1.4-8.7%), and 5.6% (1.3-10.0%), respectively. This translates to NNTs (95% CI) of 26 (15-98), 24 (14-84), 20 (11-70), and 18 (10-77). The 5-year CIR (95% CI) was 4.8% (1.3-8.2%), 5.0% (1.3-8.7%), 6.1% (1.7-10.5%), and 7.7% (2.3-13.2%), respectively. Consistent results were obtained for 5-point MACE, additionally including coronary revascularization and unstable angina.

CONCLUSION

Among patients with ASCVD and elevated triglyceride levels, icosapent ethyl significantly reduces the risk of MACE irrespective of baseline CVD risk, though absolute benefits are largest for patients at the highest risk.

Icosapent ethyl modulates circulating vascular regenerative cell content: The IPE-PREVENTION CardioLink-14 trial

BACKGROUND

REDUCE-IT (Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial) showed that icosapent ethyl (IPE) reduced major adverse cardiovascular events by 25%. Since the underlying mechanisms for these benefits are not fully understood, the IPE-PREVENTION CardioLink-14 trial (ClinicalTrials.gov: NCT04562467) sought to determine if IPE regulates vascular regenerative (VR) cell content in people with mild to moderate hypertriglyceridemia.

METHODS

Seventy statin-treated individuals with triglycerides ≥1.50 and <5.6 mmol/L and either atherosclerotic cardiovascular disease or type 2 diabetes with additional cardiovascular risk factors were randomized to IPE (4 g/day) or usual care. VR cells with high aldehyde dehydrogenase activity (ALDHhi) were isolated from blood collected at the baseline and 3-month visits and characterized with lineage-specific cell surface markers. The primary endpoint was the change in frequency of pro-vascular ALDHhiside scatter (SSC)lowCD133+ progenitor cells. Change in frequencies of ALDHhiSSCmid monocyte and ALDHhiSSChi granulocyte precursor subsets, reactive oxygen species production, serum biomarkers, and omega-3 levels were also evaluated.

FINDINGS

Baseline characteristics, cardiovascular risk factors, and medications were balanced between the groups. Compared to usual care, IPE increased the mean frequency of ALDHhiSSClowCD133+ cells (-1.00% ± 2.45% vs. +7.79% ± 1.70%; p = 0.02), despite decreasing overall ALDHhiSSClow cell frequency. IPE assignment also reduced oxidative stress in ALDHhiSSClow progenitors and increased ALDHhiSSChi granulocyte precursor cell content.

CONCLUSIONS

IPE-PREVENTION CardioLink-14 provides the first translational evidence that IPE can modulate VR cell content and suggests a novel mechanism that may underlie the cardioprotective effects observed with IPE in REDUCE-IT.

FUNDING

HLS Therapeutics provided the IPE in kind and had no role in the study design, conduct, analyses, or interpretation.

Pemafibrate and other triglyceride-lowering therapies to reduce risk of cardiovascular and metabolic disease

PURPOSE OF REVIEW

Although high triglycerides are consistently associated with elevated risk of cardiovascular disease (CVD), therapies that reduce triglyceride levels have inconsistently translated into reduced CVD risk.

RECENT FINDINGS

To date, three clinical trials have tested triglyceride-lowering therapies in patients with hypertriglyceridemia (HTG) and elevated risk of incident/recurrent CVD. In REDUCE-IT (Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial), assignment to IPE, a highly purified eicosapentanoic acid (EPA), resulted in a 25% reduction in nonfatal myocardial infarction), nonfatal stroke, cardiovascular death, coronary revascularization and hospitalization for unstable angina. By contrast, the combination of EPA and docosahexanoic acid (DHA) carboxylic fatty acids used in the STRENGTH trial (Statin Residual Risk With Epanova in High Cardiovascular Risk Patients With Hypertriglyceridemia) failed to reduce CVD risk. Most recently, PROMINENT (Pemafibrate to Reduce Cardiovascular Outcomes by Reducing Triglycerides in Patients with Diabetes) also failed to demonstrate reduction in CVD events despite use of a potent triglyceride-lowering, fibric-acid derivative. However, improvement in HTG-associated metabolic complications (e.g. nonalcoholic fatty liver disease) was observed with pemafibrate as well as with another potent triglyceride-lowering therapy (i.e. pegozafermin). Moreover, trials are underway evaluating whether the most fatal metabolic complication of HTG, pancreatitis, may be reduced with highly potent triglyceride-lowering therapies (e.g. apolipoprotein C3 inhibitors).

SUMMARY

Taken together, HTG is associated with increased risk of CVD and attendant adverse metabolic sequalae. To this end, a potentially promising and evidence-based landscape is emerging for treating a clinical phenotype that in the past has been insufficiently addressed.

Do patients benefit from omega-3 fatty acids?

Omega-3 fatty acids (O3FAs) possess beneficial properties for cardiovascular (CV) health and elevated O3FA levels are associated with lower incident risk for CV disease (CVD.) Yet, treatment of at-risk patients with various O3FA formulations has produced disparate results in large, well-controlled and well-conducted clinical trials. Prescription formulations and fish oil supplements containing low-dose mixtures of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have routinely failed to prevent CV events in primary and secondary prevention settings when added to contemporary care, as shown most recently in the STRENGTH and OMEMI trials. However, as observed in JELIS, REDUCE-IT, and RESPECT-EPA, EPA-only formulations significantly reduce CVD events in high-risk patients. The CV mechanism of action of EPA, while certainly multifaceted, does not depend solely on reductions of circulating lipids, including triglycerides (TG) and LDL, and event reduction appears related to achieved EPA levels suggesting that the particular chemical and biological properties of EPA, as compared to DHA and other O3FAs, may contribute to its distinct clinical efficacy. In vitro and in vivo studies have shown different effects of EPA compared with DHA alone or EPA/DHA combination treatments, on atherosclerotic plaque morphology, LDL and membrane oxidation, cholesterol distribution, membrane lipid dynamics, glucose homeostasis, endothelial function, and downstream lipid metabolite function. These findings indicate that prescription-grade, EPA-only formulations provide greater benefit than other O3FAs formulations tested. This review summarizes the clinical findings associated with various O3FA formulations, their efficacy in treating CV disease, and their underlying mechanisms of action.

A Practical Approach to the Management of Residual Cardiovascular Risk: United Arab Emirates Expert Consensus Panel on the Evidence for Icosapent Ethyl and Omega-3 Fatty Acids

PURPOSE

Patients with hyperlipidemia treated with statins remain at a residual cardiovascular (CV) risk. Omega-3 polyunsaturated fatty acids hold the potential to mitigate the residual CV risk in statin-treated patients, with persistently elevated triglyceride (TG) levels.

METHOD

We reviewed the current evidence on the use of icosapent ethyl (IPE), an omega-3 fatty acid yielding a pure form of eicosapentaenoic acid.

RESULTS

REDUCE-IT reported a significant 25% reduction in CV events, including the need for coronary revascularization, the risk of fatal/nonfatal myocardial infarction, stroke, hospitalization for unstable angina, and CV death in patients on IPE, unseen with other omega-3 fatty acids treatments. IPE was effective in all patients regardless of baseline CV risk enhancers (TG levels, type-2 diabetes status, weight status, prior revascularization, or renal function). Adverse events (atrial fibrillation/flutter) related to IPE have occurred mostly in patients with prior atrial fibrillation. Yet, the net clinical benefit largely exceeded potential risks. The combination with other omega-3 polyunsaturated fatty acids, in particular DHA, eliminated the effect of EPA alone, as reported in the STRENGTH and OMEMI trials. Adding IPE to statin treatment seems to be cost-effective, especially in the context of secondary prevention of CVD, decreasing CV event frequency and subsequently the use of healthcare resources.

CONCLUSION

Importantly, IPE has been endorsed by 20 international medical societies as a statin add-on treatment in patients with dyslipidemia and high CV risk. Robust medical evidence supports IPE as a pillar in the management of dyslipidemia.

Lipidomic studies reveal two specific circulating phosphatidylcholines as surrogate biomarkers of the omega-3 index

Optimal dietary intake of omega-3 long-chain polyunsaturated fatty acids (n3-LCPUFAs) is critical to human health across the lifespan. However, omega-3 index (O3I) determination is not routinely assessed due to complicated procedures for n3-LCPUFA analysis from the phospholipid (PL) fraction of erythrocytes. Herein, a high-throughput method for lipidomics based on multisegment injection-nonaqueous capillary electrophoresis-mass spectrometry was applied to identify circulating PLs as surrogate biomarkers of O3I in two randomized placebo-controlled trials. An untargeted lipidomic data workflow using a subgroup analysis of serum extracts from sunflower oil versus high-dose fish oil (FO)-supplemented participants revealed that ingested n3-LCPUFAs were primarily distributed as their phosphatidylcholines (PCs) relative to other PL classes. In both high-dose FO (5.0 g/day) and EPA-only trials (3.0 g/day), PC (16:0_20:5) was the most responsive PL, whereas PC (16:0_22:6) was selective to DHA-only supplementation. We also demonstrated that the sum concentration of both these PCs in fasting serum or plasma samples was positively correlated to the O3I following FO (r = 0.708, P = 1.02 × 10-11, n = 69) and EPA- or DHA-only supplementation (r = 0.768, P = 1.01 × 10-33, n = 167). Overall, DHA was more effective in improving the O3I (ΔO3I = 4.90 ± 1.33%) compared to EPA (ΔO3I = 2.99 ± 1.19%) in young Canadian adults who had a poor nutritional status with an O3I (3.50 ± 0.68%) at baseline. Our method enables the rapid assessment of the O3I by directly measuring two circulating PC species in small volumes of blood, which may facilitate screening applications for population and precision health.

Effectiveness of icosapent ethyl on first and total cardiovascular events in patients with metabolic syndrome, but without diabetes: REDUCE-IT MetSyn

Aims

Metabolic syndrome (MetSyn) is associated with high risk of cardiovascular (CV) events, irrespective of statin therapy. In the overall REDUCE-IT study of statin-treated patients, icosapent ethyl (IPE) reduced the risk of the primary composite endpoint (CV death, non-fatal myocardial infarction, non-fatal stroke, coronary revascularization, or unstable angina requiring hospitalization) and the key secondary composite endpoint (CV death, non-fatal myocardial infarction, or non-fatal stroke).

Methods and results

REDUCE-IT was an international, double-blind trial that randomized 8179 high CV risk statin-treated patients with controlled LDL cholesterol and elevated triglycerides, to IPE 4 g/day or placebo. The current study evaluated the pre-specified patient subgroup with a history of MetSyn, but without diabetes at baseline. Among patients with MetSyn but without diabetes at baseline (n = 2866), the majority (99.8%) of this subgroup was secondary prevention patients. Icosapent ethyl use was associated with a 29% relative risk reduction for the first occurrence of the primary composite endpoint [hazard ratio: 0.71; 95% confidence interval (CI): 0.59-0.84; P < 0.0001, absolute risk reduction (ARR) = 5.9%; number needed to treat = 17] and a 41% reduction in total (first plus subsequent) events [rate ratio: 0.59; (95% CI: 0.48-0.72); P < 0.0001] compared with placebo. The risk for the key secondary composite endpoint was reduced by 20% (P = 0.05) and a 27% reduction in fatal/non-fatal MI (P = 0.03), 47% reduction in urgent/emergent revascularization (P < 0.0001), and 58% reduction in hospitalization for unstable angina (P < 0.0001). Non-statistically significant reductions were observed in cardiac arrest (44%) and sudden cardiac death (34%).

Conclusion

In statin-treated patients with a history of MetSyn, IPE significantly reduced the risk of first and total CV events in REDUCE-IT. The large relative and ARRs observed supports IPE as a potential therapeutic consideration for patients with MetSyn at high CV risk. Registration REDUCE-IT ClinicalTrials.gov number: NCT01492361.

Triglycerides revisited: is hypertriglyceridaemia a necessary therapeutic target in cardiovascular disease?

Despite the atherosclerotic cardiovascular disease (ASCVD) risk reduction achieved by low-density lipoprotein cholesterol (LDL-C) lowering therapy, residual ASCVD risk still exists. Previous epidemiological studies have suggested high plasma triglyceride (TG) levels as a risk factor or risk marker for ASCVD independent of LDL-C levels. In this review, we highlighted the underlying pathophysiology of hypertriglyceridaemia, the mechanistic action of therapeutic agents, the interpretation of conflicting results on recent clinical trials, and the present options for primary and secondary prevention. The benefits of fibrates-induced reduction in TG and increase in high-density lipoprotein cholesterol might outweigh the disadvantages of increasing LDL-C levels in primary prevention. In secondary CVD prevention, using eicosapentaenoic acid without docosahexaenoic acid, in addition to statins, will be beneficial. This comprehensive review may prove useful for the development of novel approaches that target hypertriglyceridaemia in future.

Fibrates, Hypertriglyceridemia, and CVD Risk: Where Do We Stand After the PROMINENT Trial for Triglyceride Lowering?

PURPOSE OF REVIEW

To evaluate recent clinical trials focusing on patients with hypertriglyceridemia.

RECENT FINDINGS

Randomized clinical trials have recently been undertaken in hypertriglyceridemic patients to determine whether effective reductions in triglycerides would improve cardiovascular disease (CVD) outcomes. However, the fibric acid derivative, pemafibrate, failed to reduce cardiovascular events despite significant reductions (~ 25-35%) in triglyceride levels and despite background statin therapy. In contrast, icosapent ethyl, a highly purified omega-3 fatty acid was previously shown to reduce CVD events in hypertriglyceridemic patients, despite more modest reductions (~ 20%) in triglyceride levels in statin treated patients. The divergent results obtained in patients with hypertriglyceridemia (HTG), a group at particularly high risk of CVD, especially when coupled with other risk factors, indicates that triglyceride lowering in of itself is insufficient to offset CVD risk. Rather, the effectiveness of therapy in this high-risk cohort may be the result of the suppression of the inherent atherogenic properties associated with HTG.

Eicosapentaenoic acid (EPA) reduces pulmonary endothelial dysfunction and inflammation due to changes in protein expression during exposure to particulate matter air pollution

AIMS

Inhalation of air pollution small particle matter (PM) is a leading cause of cardiovascular (CV) disease. Exposure to PMs causes endothelial cell (EC) dysfunction as evidenced by nitric oxide (NO) synthase uncoupling, vasoconstriction and inflammation. Eicosapentaenoic acid (EPA) has been shown to mitigate PM-induced adverse cardiac changes in patients receiving omega-3 fatty acid supplementation. We set out to determine the pro-inflammatory effects of multiple PMs (urban and fine) on pulmonary EC NO bioavailability and protein expression, and whether EPA restores EC function under these conditions.

METHODS AND RESULTS

We pretreated pulmonary ECs with EPA and then exposed them to urban or fine air pollution PMs. LC/MS-based proteomic analysis to assess relative expression levels. Expression of adhesion molecules was measured by immunochemistry. The ratio of NO to peroxynitrite (ONOO-) release, an indication of eNOS coupling, was measured using porphyrinic nanosensors following calcium stimulation. Urban/fine PMs also modulated 9/12 and 13/36 proteins, respectively, linked to platelet and neutrophil degranulation pathways and caused > 50% (p < 0.001) decrease in the stimulated NO/ONOO- release ratio. EPA treatment altered expression of proteins involved in these inflammatory pathways, including a decrease in peroxiredoxin-5 and an increase in superoxide dismutase-1. EPA also increased expression of heme oxygenase-1 (HMOX1), a cytoprotective protein, by 2.1-fold (p = 0.024). EPA reduced elevations in sICAM-1 levels by 22% (p < 0.01) and improved the NO/ONOO- release ratio by > 35% (p < 0.05).

CONCLUSION

These cellular changes may contribute to anti-inflammatory, cytoprotective and lipid changes associated with EPA treatment during air pollution exposure.

A Critical Review of Icosapent Ethyl in Cardiovascular Risk Reduction

Icosapent ethyl (IPE) was the first fish oil product the US Food and Drug Administration (FDA) approved to reduce the risk of atherosclerotic cardiovascular disease (ASCVD) in adults. IPE is an esterified version of eicosapentaenoic acid (EPA) and acts as a prodrug in the body to exert its effects. IPE affects the body primarily through triglyceride (TG) reduction and was initially indicated for hypertriglyceridemia in addition to statin therapy or for patients with statin intolerances. Various studies have investigated this agent, and multiple subanalyses have been conducted since the FDA approval. These subanalyses have assessed factors such as sex, statin therapy, high-sensitivity C-reactive protein levels (hs-CRP), and various inflammatory biomarkers in groups of patients taking IPE. This article aims to provide a critical review of the clinical data available regarding cardiovascular benefits of IPE in patients with ASCVD and its value as a treatment option for patients with elevated TG levels.