Drug Monograph

Icosapent Ethyl (Vascepa)

icosapent ethyl

Omega-3 Fatty Acid Ethyl Ester (EPA) · Oral
Pharmacokinetic Profile
Half-Life
~89 h (EPA)
Metabolism
Hepatic β-oxidation (CYP minor role)
Protein Binding
>99% (unesterified EPA)
Bioavailability
Absorbed via lymphatic system; take with food
Volume of Distribution
~88 L at steady state
Clinical Information
Drug Class
Omega-3 fatty acid (purified EPA ethyl ester)
Available Doses
0.5 g and 1 g capsules
Route
Oral, twice daily with food
Renal Adjustment
Not studied; not renally excreted
Hepatic Adjustment
Monitor ALT/AST periodically
Pregnancy
Insufficient data; consider benefit vs risk
Lactation
EPA present in human milk; weigh benefits vs risks
Schedule / Legal
Prescription only (not controlled)
Generic Available
Yes
Rx

Icosapent Ethyl Indications

IndicationApproved PopulationTherapy TypeStatus
Cardiovascular risk reduction — reduce risk of MI, stroke, coronary revascularization, and unstable angina requiring hospitalization in patients with TG ≥150 mg/dL and established CVD or diabetes with ≥2 additional CV risk factorsAdults on maximally tolerated statin therapyAdjunct to statinFDA Approved
Severe hypertriglyceridemia (≥500 mg/dL) — reduce TG levelsAdultsAdjunctive to dietFDA Approved

Icosapent ethyl is the only omega-3 fatty acid preparation with demonstrated cardiovascular outcomes benefit. The REDUCE-IT trial (n=8179, median follow-up 4.9 years) showed a 25% relative risk reduction in the primary composite endpoint of CV death, nonfatal MI, nonfatal stroke, coronary revascularization, or unstable angina requiring hospitalization (17.2% vs 22.0%; HR 0.75, 95% CI 0.68-0.83, P<0.001; NNT 21). The key secondary endpoint of CV death, nonfatal MI, or nonfatal stroke was also significantly reduced (11.2% vs 14.8%; HR 0.74, P<0.001), as was cardiovascular death alone (4.3% vs 5.2%; HR 0.80, P=0.03). This benefit was observed on top of statin therapy in patients with median LDL-C of 75 mg/dL and median TG of 216 mg/dL, suggesting mechanisms beyond triglyceride lowering alone.

Limitation of Use

The effect of icosapent ethyl on the risk for pancreatitis in patients with severe hypertriglyceridemia has not been determined (FDA PI). Icosapent ethyl differs from mixed omega-3 preparations containing both EPA and DHA; trials of EPA+DHA combinations (STRENGTH, VITAL) did not demonstrate cardiovascular benefit, highlighting the importance of the specific purified EPA formulation.

Dose

Dosing

Adult Dosing by Clinical Scenario

Clinical ScenarioStarting DoseMaintenance DoseMaximum DoseNotes
CV risk reduction — statin-treated patient with TG ≥150 mg/dL and established ASCVD2 g BID with food2 g BID with food4 g/dayTake as two 1 g capsules BID or four 0.5 g capsules BID; must be on maximally tolerated statin
Swallow capsules whole; do not crush, break, or chew
CV risk reduction — statin-treated patient with TG ≥150 mg/dL, diabetes, and ≥2 additional CV risk factors2 g BID with food2 g BID with food4 g/daySame dosing as established CVD; additional risk factors include age ≥50, hypertension, smoking, etc.
Assess lipid levels before initiating; manage secondary causes of elevated TG
Severe hypertriglyceridemia (≥500 mg/dL) — TG reduction2 g BID with food2 g BID with food4 g/dayAdjunct to diet; identify and manage secondary causes (diabetes, hypothyroidism, medications, alcohol)
Pancreatitis risk reduction not established for this indication
Clinical Pearl — Fixed Dose, No Titration

Icosapent ethyl uses a single dose of 4 g/day for all approved indications. There is no dose titration, and the dose is the same for both the CV risk reduction and hypertriglyceridemia indications. The drug must be taken with food to facilitate absorption through the lymphatic system. Two capsule sizes are available (0.5 g and 1 g), offering flexibility in pill burden. Unlike dietary omega-3 supplements, icosapent ethyl is a highly purified (≥96%) EPA ethyl ester that does not contain DHA, which is a pharmacologically important distinction given the differing trial outcomes between EPA-only and EPA+DHA preparations.

PK

Pharmacology

Mechanism of Action

Icosapent ethyl is an ethyl ester of eicosapentaenoic acid (EPA), a long-chain polyunsaturated omega-3 fatty acid. After oral administration, icosapent ethyl is de-esterified to release free EPA, which is then absorbed in the small intestine and enters systemic circulation via the lymphatic system. EPA reduces hepatic VLDL-TG synthesis and secretion while enhancing triglyceride clearance from circulating VLDL particles. Proposed mechanisms include increased beta-oxidation, inhibition of diacylglycerol acyltransferase (DGAT), decreased hepatic lipogenesis, and increased lipoprotein lipase activity. The mechanisms contributing to cardiovascular event reduction are not completely understood and are likely multifactorial, extending beyond triglyceride lowering to include anti-inflammatory, anti-thrombotic, membrane-stabilising, and anti-atherosclerotic effects. Increased EPA incorporation into cell membranes and atherosclerotic plaques, along with an increased EPA-to-arachidonic acid ratio, may contribute to the observed cardiovascular benefits.

ADME Profile

ParameterValueClinical Implication
AbsorptionDe-esterified to EPA and absorbed in small intestine; enters circulation via lymphatic system; Tmax ~5 h; steady state in 7-10 days; must take with foodLymphatic absorption bypasses first-pass hepatic metabolism; food is required for adequate absorption; no formal food effect study conducted
DistributionVss ~88 L; majority of EPA incorporated into phospholipids, triglycerides, and cholesteryl esters; <1% as unesterified fatty acid; protein binding >99% (unesterified EPA)Extensive tissue distribution; EPA integrates into cell membranes and atherosclerotic plaques, which may contribute to cardiovascular benefit beyond lipid lowering
MetabolismPrimarily hepatic β-oxidation similar to dietary fatty acids; β-oxidation converts EPA carbon chain to acetyl-CoA for energy via Krebs cycle; CYP enzymes play minor role; does not inhibit CYP1A2, 2B6, 2C8, 2C9, 2C19, 2D6, 2E1, or 3A4Minimal CYP-mediated drug interaction risk; this is a key advantage over gemfibrozil; no clinically significant interaction with atorvastatin, warfarin, omeprazole, or rosiglitazone observed
Eliminationt½ ~89 h (EPA); clearance ~684 mL/h at steady state; not renally excretedLong half-life supports consistent EPA tissue levels with BID dosing; no renal dose adjustment required; however, drug has not been studied in renal or hepatic impairment
SE

Side Effects

≥10% Very Common
Adverse EffectIncidenceClinical Note
Bleeding (any type)12% vs 10% placeboOverall increased risk; incidence greater in patients on concomitant antithrombotic agents (aspirin, clopidogrel, warfarin); primarily minor bleeding events
1-10% Common
Adverse EffectIncidenceClinical Note
Musculoskeletal pain≥3% (≥1% more than placebo)Reported in REDUCE-IT CV outcomes trial; includes myalgia, arthralgia, and bone pain
Peripheral oedema≥3% (≥1% more than placebo)Swelling of extremities; monitor for underlying cardiac or renal causes if significant
Constipation≥3% (≥1% more than placebo)GI effect; manage with dietary fibre and hydration
Gout≥3% (≥1% more than placebo)Elevated uric acid may occur; relevant in patients with pre-existing hyperuricaemia
Atrial fibrillation3.1% vs 2.1% placebo (requiring hospitalisation)HR 1.5 (95% CI 1.14-1.98); higher risk in patients with prior AF/AFL history; adjudicated events requiring ≥24h hospitalisation
Arthralgia≥1% more than placeboReported in the hypertriglyceridemia trials (MARINE/ANCHOR); joint pain
Oropharyngeal pain≥1% more than placeboReported in hypertriglyceridemia trials; throat discomfort related to capsule ingestion
Serious Serious (Regardless of Frequency)
Adverse EffectEstimated FrequencyTypical OnsetRequired Action
Atrial fibrillation / atrial flutter requiring hospitalisation3.1% vs 2.1% placebo (HR 1.5, CI 1.14-1.98)Any time during therapy; higher risk with prior AF/AFL historyEvaluate for symptoms of arrhythmia (palpitations, dizziness, dyspnoea); ECG if symptomatic; cardiology referral as appropriate; consider risk-benefit of continuation
Serious bleeding events2.7% vs 2.1% placebo (P=0.06)Any time; risk increased with concomitant antithrombotic therapyMonitor patients on concomitant anticoagulants/antiplatelets; assess bleeding risk before initiation; no fatal drug-related bleeding events in REDUCE-IT
Anaphylactic reactionVery rare; potential in patients with fish/shellfish allergyAny timeDiscontinue immediately; emergency treatment; icosapent ethyl is derived from fish oil — advise patients with known fish/shellfish hypersensitivity
Discontinuation Discontinuation Rates
REDUCE-IT (Median 4.9 years)
7.9% vs 8.2% placebo
No significant difference in discontinuation rates between icosapent ethyl and placebo; overall serious TEAE rates were also similar (30.6% vs 30.7%)
Pediatric
N/A
Safety and effectiveness not established in pediatric patients
Atrial Fibrillation Risk — Key Safety Signal

Atrial fibrillation or flutter requiring hospitalisation occurred in 3.1% of patients on icosapent ethyl versus 2.1% on placebo in REDUCE-IT (HR 1.5, 95% CI 1.14-1.98). The risk was higher in patients with a previous history of AF or AFL. Before initiating icosapent ethyl, clinicians should assess individual risk for atrial arrhythmias, particularly in elderly patients and those with structural heart disease. For most patients, the cardiovascular benefit (NNT 21 for primary composite endpoint) outweighs this risk, but patients should be counselled about symptoms of arrhythmia.

Int

Drug Interactions

Icosapent ethyl has a remarkably clean drug interaction profile. EPA is metabolised primarily by hepatic beta-oxidation and does not significantly inhibit or induce CYP enzymes (1A2, 2B6, 2C8, 2C9, 2C19, 2D6, 2E1, 3A4). No clinically significant pharmacokinetic interactions were observed with atorvastatin, warfarin, omeprazole, or rosiglitazone in dedicated studies. The only clinically relevant interaction is a pharmacodynamic one: increased bleeding risk when combined with anticoagulants or antiplatelet agents.

ModerateAnticoagulants (Warfarin, DOACs)
MechanismPharmacodynamic: omega-3 fatty acids may prolong bleeding time; additive effect with anticoagulants
EffectIncreased bleeding risk; overall bleeding 12% vs 10% in REDUCE-IT, with higher rates in patients on antithrombotic agents
ManagementMonitor patients for signs of bleeding; no warfarin dose adjustment needed based on PK studies, but clinical vigilance required
FDA PI
ModerateAntiplatelet Agents (Aspirin, Clopidogrel)
MechanismPharmacodynamic: additive inhibition of platelet aggregation and prolongation of bleeding time
EffectGreater incidence of bleeding in patients on concomitant antithrombotic medications in REDUCE-IT
ManagementMonitor for bleeding; no dose adjustment needed; most REDUCE-IT patients were on antiplatelet therapy and net clinical benefit was still positive
FDA PI / REDUCE-IT
MinorStatins (Atorvastatin and others)
MechanismNo pharmacokinetic interaction; no effect on atorvastatin, 2-hydroxyatorvastatin, or 4-hydroxyatorvastatin exposure
EffectSafe to co-administer; icosapent ethyl is specifically indicated as an adjunct to statin therapy
ManagementNo dose adjustment required for either drug; continue both as prescribed
FDA PI / PK study
MinorOther Tested Drugs (Warfarin PK, Omeprazole, Rosiglitazone)
MechanismNo CYP inhibition or induction; icosapent ethyl does not affect PK of these agents
EffectNo change in plasma levels or pharmacokinetic parameters of co-administered drugs
ManagementNo dose adjustments required
FDA PI / PK studies
Mon

Monitoring

  • Lipid Panel Before initiation, then periodically
    Routine
    Assess triglycerides and other lipid levels before starting therapy. Identify and manage secondary causes of elevated TG (diabetes, hypothyroidism, medications, alcohol). Periodic reassessment to evaluate lipid response. In REDUCE-IT, median baseline TG was 216 mg/dL.
  • Liver Function Tests Periodically in hepatic impairment
    Routine
    ALT and AST should be monitored periodically in patients with hepatic impairment (FDA PI). Icosapent ethyl has not been studied in patients with hepatic impairment.
  • Heart Rhythm Ongoing clinical assessment
    Routine
    Counsel patients about symptoms of atrial fibrillation or flutter (palpitations, lightheadedness, dizziness, dyspnoea, chest discomfort). REDUCE-IT showed 3.1% vs 2.1% AF/AFL requiring hospitalisation (HR 1.5). Increased risk in patients with prior AF/AFL history.
  • Bleeding Ongoing, especially with antithrombotic co-use
    Trigger-based
    Monitor patients receiving concomitant anticoagulants and/or antiplatelet agents for bleeding. REDUCE-IT showed 12% vs 10% overall bleeding and 2.7% vs 2.1% serious bleeding (P=0.06).
  • Allergic Reactions At initiation and ongoing
    Trigger-based
    Icosapent ethyl is derived from fish oil. Although the risk is not quantified, patients with fish or shellfish allergies should be informed about potential allergic reactions and advised to discontinue if symptoms occur.
CI

Contraindications & Cautions

Absolute Contraindications

  • Known hypersensitivity (e.g., anaphylactic reaction) to icosapent ethyl or any of its components (FDA PI)

Relative Contraindications (Specialist Input Recommended)

  • Known allergy to fish and/or shellfish — icosapent ethyl is derived from fish oil; cross-reactivity risk is unknown but patients should be informed and monitored
  • History of atrial fibrillation or atrial flutter — increased risk of AF/AFL requiring hospitalisation (HR 1.5); requires documented risk-benefit assessment
  • High bleeding risk — patients on triple antithrombotic therapy, recent major surgery, or active bleeding disorders; weigh bleeding risk against cardiovascular benefit

Use with Caution

  • Concomitant anticoagulant or antiplatelet therapy — monitor for bleeding; most REDUCE-IT patients were on antiplatelets and still showed net benefit
  • Hepatic impairment — not studied; monitor ALT/AST periodically
  • Renal impairment — not studied; however, icosapent ethyl is not renally excreted
  • Pregnancy — insufficient human data; animal studies showed non-dose-related developmental findings at human-equivalent exposures; use only if benefit justifies risk
FDA Warnings and Precautions Atrial Fibrillation/Flutter and Bleeding Risk

The FDA label for icosapent ethyl carries specific warnings regarding increased risk of atrial fibrillation or flutter requiring hospitalisation (127 patients [3%] on icosapent ethyl vs 84 [2%] on placebo; HR 1.5, 95% CI 1.14-1.98) and increased bleeding (482 patients [12%] vs 404 [10%] overall; serious bleeding 111 [2.7%] vs 85 [2.1%]). The incidence of AF was greater in patients with prior AF history, and bleeding was greater with concomitant antithrombotic therapy. These risks should be weighed against the significant 25% relative reduction in MACE demonstrated in REDUCE-IT.

Pt

Patient Counselling

Purpose of Therapy

Icosapent ethyl is a prescription medication derived from purified fish oil (EPA) used alongside your statin to further reduce your risk of heart attack, stroke, and other cardiovascular events. For patients with very high triglycerides, it also helps lower these fat levels in the blood. It is not a substitute for diet, exercise, or statin therapy — it works in addition to these measures.

How to Take

Take two capsules twice daily with food (4 capsules total per day). Swallow capsules whole — do not break, crush, dissolve, or chew them. If you miss a dose, take it as soon as you remember. If you miss an entire day, do not double the dose — simply resume your normal schedule.

Heart Rhythm Changes
Tell patientIcosapent ethyl may slightly increase the risk of an irregular heart rhythm called atrial fibrillation. This risk is higher if you have had heart rhythm problems in the past. For most patients, the heart protection benefits outweigh this small risk.
Call prescriberIf you experience a sensation of your heart beating fast or irregularly, lightheadedness, dizziness, shortness of breath, chest discomfort, or if you faint.
Bleeding
Tell patientThis medication may increase your tendency to bleed, especially if you also take blood thinners (warfarin, apixaban) or antiplatelet medications (aspirin, clopidogrel). Inform all healthcare providers that you are taking icosapent ethyl before any surgical or dental procedures.
Call prescriberIf you notice unusual bruising, prolonged bleeding from cuts, blood in urine or stool, or any signs of unexpected bleeding.
Fish or Shellfish Allergy
Tell patientIcosapent ethyl is made from fish oil. If you have a known allergy to fish or shellfish, discuss this with your prescriber before starting the medication. The risk of allergic reaction is not well quantified but should be considered.
Call prescriberStop taking icosapent ethyl immediately and seek medical attention if you develop signs of an allergic reaction: rash, hives, itching, swelling of the face/lips/tongue/throat, difficulty breathing, or dizziness.
Dietary Supplements vs Prescription
Tell patientIcosapent ethyl is a prescription medication that is highly purified and different from over-the-counter fish oil supplements. Over-the-counter omega-3 supplements have not been shown to reduce heart attack and stroke risk in clinical trials. Do not substitute dietary supplements for your prescribed medication without consulting your prescriber.
Call prescriberBefore starting any new supplements or vitamins, as some may interact with your medications.
Ref

Sources

Regulatory (PI / SmPC)
  1. Vascepa (icosapent ethyl) capsules — Full Prescribing Information. Amarin Pharma, Inc. Revised 05/2024. DailyMed Primary source for all indications, dosing, contraindications, warnings, adverse reactions, and pharmacokinetic data cited in this monograph.
Key Clinical Trials
  1. Bhatt DL, Steg PG, Miller M, et al. Cardiovascular risk reduction with icosapent ethyl for hypertriglyceridemia (REDUCE-IT). N Engl J Med. 2019;380(1):11-22. doi:10.1056/NEJMoa1812792 Landmark CV outcomes trial (n=8179, median 4.9 years) demonstrating 25% RRR in MACE with icosapent ethyl 4 g/day vs placebo; source for all REDUCE-IT efficacy and safety data.
  2. Bhatt DL, Steg PG, Miller M, et al. Effects of icosapent ethyl on total ischemic events: from REDUCE-IT. J Am Coll Cardiol. 2019;73(22):2791-2802. doi:10.1016/j.jacc.2019.02.032 REDUCE-IT total events analysis showing 30% reduction in total (first and subsequent) ischemic events with icosapent ethyl.
  3. Bays HE, Ballantyne CM, Kastelein JJ, Isaacsohn JL, Braeckman RA, Soni PN. Eicosapentaenoic acid ethyl ester (AMR101) therapy in patients with very high triglyceride levels (MARINE). Am J Cardiol. 2011;108(5):682-690. doi:10.1016/j.amjcard.2011.04.015 Pivotal MARINE trial (TG ≥500 mg/dL) providing efficacy data for the severe hypertriglyceridemia indication and initial safety profile.
  4. Ballantyne CM, Bays HE, Kastelein JJ, et al. Efficacy and safety of eicosapentaenoic acid ethyl ester (AMR101) therapy in statin-treated patients with persistent high triglycerides (ANCHOR). Am J Cardiol. 2012;110(7):984-992. doi:10.1016/j.amjcard.2012.05.031 ANCHOR trial demonstrating TG reduction in statin-treated patients with TG 200-499 mg/dL; source for additional safety data including arthralgia and oropharyngeal pain.
  5. Budoff MJ, Bhatt DL, Kinninger A, et al. Effect of icosapent ethyl on progression of coronary atherosclerosis in patients with elevated triglycerides on statin therapy (EVAPORATE). JAMA. 2020;324(1):68-74. doi:10.1001/jama.2020.9613 EVAPORATE trial showing regression of coronary plaque volume with icosapent ethyl, supporting anti-atherosclerotic mechanisms beyond TG lowering.
Guidelines
  1. Grundy SM, Stone NJ, Bailey AL, et al. 2018 AHA/ACC Guideline on the Management of Blood Cholesterol. Circulation. 2019;139(25):e1082-e1143. doi:10.1161/CIR.0000000000000625 ACC/AHA cholesterol guideline providing context for the role of icosapent ethyl in ASCVD risk management.
  2. Skulas-Ray AC, Wilson PWF, Harris WS, et al. Omega-3 fatty acids for the management of hypertriglyceridemia: a science advisory from the American Heart Association. Circulation. 2019;140(12):e673-e691. doi:10.1161/CIR.0000000000000709 AHA science advisory on omega-3 fatty acids for hypertriglyceridemia, endorsing prescription omega-3s at 4 g/day for severe hypertriglyceridemia.
Mechanistic / Basic Science
  1. Mason RP, Libby P, Bhatt DL. Emerging mechanisms of cardiovascular protection for the omega-3 fatty acid eicosapentaenoic acid. Arterioscler Thromb Vasc Biol. 2020;40(4):802-814. doi:10.1161/ATVBAHA.119.313286 Comprehensive review of proposed mechanisms of EPA cardiovascular benefit including anti-inflammatory, anti-oxidative, membrane-stabilising, and anti-thrombotic effects.
Pharmacokinetics / Special Populations
  1. Braeckman RA, Stirtan WG, Soni PN. Pharmacokinetics of eicosapentaenoic acid in plasma and red blood cells after multiple oral dosing with icosapent ethyl in healthy subjects. Clin Pharmacol Drug Dev. 2014;3(2):101-108. doi:10.1002/cpdd.84 Comprehensive PK study characterising EPA pharmacokinetics after icosapent ethyl dosing; source for t½, Tmax, Vd, and clearance data.
  2. Braeckman RA, Manku MS, Bays HE, Stirtan WG, Soni PN. Icosapent ethyl, a pure EPA omega-3 fatty acid: effects on plasma and red blood cell fatty acids in patients with very high triglyceride levels (MARINE study). Prostaglandins Leukot Essent Fatty Acids. 2013;89(4):195-201. doi:10.1016/j.plefa.2013.07.005 PK/PD analysis from MARINE study showing dose-dependent EPA incorporation into plasma and RBC membranes.