Generalizability of the REDUCE-IT trial and cardiovascular outcomes associated with hypertriglyceridemia among patients potentially eligible for icosapent ethyl therapy: An analysis of the REduction of Atherothrombosis for Continued Health (REACH) registry

The chylomicron saga: time to focus on postprandial metabolism

Since statins have had such tremendous therapeutic success over the last three decades, the field of atherosclerosis has become somewhat LDL-centric, dismissing the relevance of triglycerides (TG), particularly chylomicrons, in atherogenesis. Nonetheless, 50% of patients who take statins are at risk of developing atherosclerotic cardiovascular disease (ASCVD) and are unable to achieve their goal LDL-C levels. This residual risk is mediated, in part by triglyceride rich lipoproteins (TRL) and their remnants. Following his seminal investigation on the subject, Zilversmit proposed that atherosclerosis is a postprandial event in 1979 (1-4). In essence, the concept suggests that remnant cholesterol-rich chylomicron (CM) and very-low density lipoprotein (VLDL) particles play a role in atherogenesis. Given the foregoing, this narrative review addresses the most recent improvements in our understanding of postprandial dyslipidemia. The primary metabolic pathways of chylomicrons are discussed, emphasizing the critical physiological role of lipoprotein lipase and apoCIII, the importance of these particles' fluxes in the postprandial period, their catabolic rate, the complexities of testing postprandial metabolism, and the role of angiopoietin-like proteins in the partition of CM during the fed cycle. The narrative is rounded out by the dysregulation of postprandial lipid metabolism in insulin resistance states and consequent CVD risk, the clinical evaluation of postprandial dyslipidemia, current research limits, and potential future study directions.

Generalizability of REDUCE-IT eligibility criteria in a large diabetes cardiovascular outcomes trial: A post hoc subgroup analysis of EMPA-REG outcome: Analysis of EMPA-REG OUTCOME using REDUCE-IT criteria

Objectives

REDUCE-IT showed that icosapent ethyl (IPE) improved cardiovascular (CV) outcomes in participants with established CV disease (CVD) or type 2 diabetes (T2D) and at least one additional risk factor plus mild-moderate hypertriglyceridemia and reasonably controlled low-density lipoprotein cholesterol (LDL-C). As the generalizability of REDUCE-IT has not been investigated in a T2D population with established CVD, this post hoc analysis investigated how many participants from EMPA-REG OUTCOME, which tested the effects of empagliflozin versus placebo on CV outcomes in participants with T2D and CVD, would have been eligible for IPE treatment, and whether CV outcomes differed based on eligibility for IPE treatment.

Methods

Participants from EMPA-REG OUTCOME were screened for inclusion using both REDUCE-IT-like criteria (baseline statin therapy, triglycerides 135-499 mg/dL and LDL-C 41-100 mg/dL) and slightly amended FDA indication criteria (triglycerides ≥150 mg/dL). Analyses were conducted to characterize the study population and CV outcomes in participants eligible for IPE versus those not eligible for IPE.

Results

Of the 7020 participants from EMPA-REG OUTCOME, 1810 (25.8%) fulfilled REDUCE-IT criteria and 3182 (45.3%) fulfilled FDA criteria for IPE treatment. Treatment effects of empagliflozin versus placebo on CV and kidney outcomes and mortality were consistent in participants meeting REDUCE-IT and FDA criteria and those who did not.

Conclusions

These results indicate that a sizable proportion of patients with diabetes and established CVD, such as those in EMPA-REG OUTCOME, may be eligible for IPE treatment to lower residual CV risk. Treatment benefit with empagliflozin was consistent, regardless of REDUCE-IT or FDA eligibility criteria.

Global eligibility and cost effectiveness of icosapent ethyl in primary and secondary cardiovascular prevention

Icosapent ethyl (IPE) is a purified eicosapentaenoic acid-only omega-3 fatty acid that significantly reduced cardiovascular (CV) events in patients receiving statins with established cardiovascular disease (CVD) and those with diabetes and additional risk factors in the pivotal REDUCE-IT trial. Since the publication of REDUCE-IT, there has been global interest in determining IPE eligibility in different patient populations, the proportion of patients who may benefit from IPE, and cost effectiveness of IPE in primary and secondary prevention settings. The aim of this review is to summarize information from eligibility and cost effectiveness studies of IPE to date. A total of sixteen studies were reviewed, involving 2,068,111 patients in the primary or secondary prevention settings worldwide. Up to forty-five percent of patients were eligible for IPE, depending on the selection criteria used (ie, REDUCE-IT criteria, US Food and Drug Administration label, Health Canada label, practice guidelines) and the population studied. Overall, eight cost-effectiveness studies across the United States, Canada, Germany, Israel, and Australia were included in this review and findings indicated that IPE is particularly cost effective in patients with established CVD.

Treatment of hypertriglyceridaemia with icosapent ethyl in patients with high/very high cardiovascular risk. Consensus document of the Sociedad Española de Cardiología [Spanish Society of Cardiology] and the Sociedad Española de Diabetes [Spanish Diabetes Society]

The Working Groups of Cardiovascular Pharmacotherapy of the Sociedad Española de Cardiología and Cardiovascular Disease of the Sociedad Española de Diabetes have prepared a consensus document on the treatment of hypertriglyceridaemia in patients with high/very-high-cardiovascular risk with icosapent ethyl, a highly purified and stable eicosapentaenoic acid ethyl ester. This document is necessary since there are differences among the three main omega-3 fatty acids and there is large-scale clinical evidence with icosapent ethyl that demonstrates that in addition to its efficacy in lowering triglyceridaemia, it reduces the risk of cardiovascular events in both patients with atherosclerotic cardiovascular disease and in those with type 2 diabetes, with a good safety profile. The number needed to treat to avoid a major cardiovascular event is analysed, comparing it with other pivotal studies of pharmacological intervention in cardiovascular prevention, and an estimate of the Spanish population likely to be treated with ethyl icosapent is carried out. These recommendations are of interest to all clinicians who manage patients with lipid metabolism disorders, cardiovascular disease and diabetes.

The potential population health impact of treating REDUCE-IT eligible US adults with Icosapent Ethyl

Objective

To explore the population health impact of treating all US adults eligible for the Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial (REDUCE-IT) with icosapent ethyl (IPE), we estimated (1) the number of ASCVD events and healthcare costs that could be prevented; and (2) medication costs.

Methods

We derived REDUCE-IT eligible cohorts in (1) the National Health and Nutrition Examination Surveys (NHANES) 2009-2014 and (2) the Optum Research Database (ORD). Population sizes were obtained from NHANES and observed first event rates (composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, unstable angina requiring hospitalization, or coronary revascularization) were estimated from the ORD. Hazard ratios from REDUCE-IT USA estimated events prevented with IPE therapy. The National Inpatient Sample estimated event costs (facility and professional) and daily IPE treatment cost was approximated at $4.59.

Results

We estimate 3.6 million US adults to be REDUCE-IT eligible, and the observed five-year first event rate without IPE of 19.0% (95% confidence interval [CI] 16.6%-19.5%) could be lowered to 13.1% (95% CI 12.8%-13.5%) with five years of IPE treatment, preventing 212,000 (uncertainty range 163,000-262,000) events. We projected the annual IPE treatment cost for all eligible persons to be $6.0 billion (95% CI $4.7-$7.5 billion), but saving $1.8 billion annually due to first events prevented (net annual cost $4.3 billion). The total five-year event rate (first and recurrent) could be reduced from 42.5% (95% CI 39.6%-45.4%) to 28.9% (95% CI 26.9-30.9%) with five years of IPE therapy, preventing 490,000 (uncertainty range 370,000-609,000) events (net annual cost $2.6 billion).

Conclusions

Treating all REDUCE-IT eligible US adults has substantial medication costs but could prevent a substantial number of ASCVD events and associated direct costs. Indirect cost savings by preventing events could outweigh much of the incurred direct costs.

Treatment With Icosapent Ethyl to Reduce Ischemic Events in Patients With Prior Percutaneous Coronary Intervention: Insights From REDUCE-IT PCI

Background

Patients who undergo percutaneous coronary intervention (PCI) are at increased risk for recurrent cardiovascular events despite aggressive medical therapy.

Methods and Results

This post hoc analysis focused on the subset of patients with prior PCI enrolled in REDUCE‐IT (Reduction of Cardiovascular Events With Icosapent Ethyl–Intervention Trial), a multicenter, randomized, double‐blind, placebo‐controlled trial of icosapent ethyl versus placebo. Icosapent ethyl was added to statins in patients with low‐density lipoprotein cholesterol <100 mg/dL and fasting triglycerides 135–499 mg/dL. The primary end point was a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, coronary revascularization, or unstable angina requiring hospitalization. There were 8179 patients randomized in REDUCE‐IT followed for a median of 4.9 years, and 3408 (41.7%) of them had a prior PCI with a median follow‐up of 4.8 years. These patients were randomized a median of 2.9 years (11 days to 30.7 years) after PCI. Among patients treated with icosapent ethyl versus placebo, there was a 34% reduction in the primary composite end point (hazard ratio [HR], 0.66; 95% CI, 0.58–0.76; P<0.001; number needed to treat^{4.8 years}=12) and a 34% reduction in the key secondary composite end point of cardiovascular death, nonfatal myocardial infarction, or nonfatal stroke (HR, 0.66; 95% CI, 0.56–0.79; P<0.001; NNT^{4.8 years}=19) versus placebo. Similarly, large reductions occurred in total coronary revascularizations and revascularization subtypes. There was also a 39% reduction in total events (rate ratio, 0.61; 95% CI, 0.52–0.72; P<0.001).

Conclusions

Among patients treated with statins with elevated triglycerides and a history of prior PCI, icosapent ethyl substantially reduced the risk of recurrent events during an average of ~5 years of follow‐up with a number needed to treat of only 12.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT01492361.