What is the recommended dosing regimen, indications, contraindications, and monitoring for ticagrelor (Brilinta) in patients with acute coronary syndrome?

Brilinta (Ticagrelor): Dosing, Indications, Contraindications, and Monitoring

Dosing Regimen

Acute Coronary Syndrome (ACS)

Administer a 180 mg oral loading dose of ticagrelor immediately upon ACS diagnosis and before any invasive procedure, followed by 90 mg twice daily for 12 months, then reduce to 60 mg twice daily thereafter. 1, 2

• Loading dose: 180 mg orally as a single dose 1, 2
• First maintenance dose: 90 mg administered 6–12 hours after the loading dose 2
• Year 1 maintenance: 90 mg twice daily for the first 12 months after ACS 1, 2
• Extended therapy (>12 months): 60 mg twice daily after completing the first year 1, 2
• Aspirin co-administration: Combine with aspirin 75–100 mg daily; never exceed 100 mg daily as higher doses blunt ticagrelor's antiplatelet effect (FDA black-box warning) 1, 2

Coronary Artery Disease Without Prior MI or Stroke

• Administer 60 mg twice daily with aspirin 75–100 mg daily 2

Acute Ischemic Stroke or TIA

• Loading dose: 180 mg orally 2
• Maintenance: 90 mg twice daily for up to 30 days 2
• Aspirin: Loading dose 300–325 mg, then 75–100 mg daily 2

Special Populations

• Elderly (≥75 years): No dose adjustment required; standard 90 mg twice daily 1
• Low body weight (≤60 kg): No dose adjustment needed 1
• Renal impairment (CKD stage ≥3b): Standard dosing appropriate 1
• Hepatic impairment: Avoid in severe hepatic impairment due to increased exposure 2

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Primary Indications

Ticagrelor is indicated to reduce cardiovascular death, myocardial infarction, and stroke in patients with ACS or a history of MI, and is superior to clopidogrel for at least the first 12 months following ACS. 1, 2

• All ACS patients (STEMI, NSTEMI, unstable angina) regardless of management strategy (PCI, medical therapy, or CABG) 1
• Post-MI patients at high ischemic risk who have tolerated initial DAPT without bleeding 1
• Coronary artery disease at high risk for first MI or stroke (efficacy established in type 2 diabetes population) 2
• Acute ischemic stroke (NIH Stroke Scale ≤5) or high-risk TIA 2
• Stent thrombosis prevention in patients stented for ACS treatment 2

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Absolute Contraindications

Do not use ticagrelor in patients with a history of intracranial hemorrhage or active pathological bleeding. 1, 2

• History of intracranial hemorrhage – high risk of recurrent ICH 1, 2
• Active pathological bleeding (e.g., peptic ulcer, active GI hemorrhage) 1, 2
• Hypersensitivity to ticagrelor or any component (e.g., angioedema) 2
• Concomitant strong CYP3A4 inhibitors (e.g., itraconazole) during treatment and up to 2 weeks after discontinuation – markedly elevated ticagrelor levels and bleeding risk 1, 2

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Critical Timing & Administration

Administer the ticagrelor loading dose immediately upon ACS diagnosis, before coronary angiography or any invasive procedure, to achieve rapid platelet inhibition within ~30 minutes. 1, 2

• STEMI: Give loading dose at first medical contact or as early as possible before primary PCI 1
• NSTEMI/Unstable angina: Administer loading dose as early as possible before or at the time of PCI 1
• Tablet administration: Can be crushed, mixed with water, and administered orally or via nasogastric tube (≥CH8) for patients unable to swallow whole 2
• Missed dose: Take next dose at scheduled time; do not double dose 2

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Monitoring & Bleeding Risk Mitigation

Mandatory Co-Interventions (Class I Recommendations)

Prescribe a proton pump inhibitor to every patient on ticagrelor-based DAPT to significantly reduce gastrointestinal bleeding risk. 1

• PPI therapy: Pantoprazole 40 mg daily preferred (lowest CYP2C19 inhibition) 1
• Aspirin dose: Maintain at 75–100 mg daily; higher doses increase bleeding without added benefit 1
• Radial access: Prefer radial over femoral artery access for PCI when performed by experienced operator 1

Common Adverse Effects

• Dyspnea: Occurs in 14–21% of patients, usually mild-to-moderate, often self-limited; led to discontinuation in 0.9–6.0% across trials 2, 3
• Ventricular pauses: Largely asymptomatic; monitor ECG in first 24 hours 3
• Non-CABG major bleeding: 4.5% vs 3.8% with clopidogrel (P=0.03) 4

Laboratory Monitoring

• Platelet function testing: False-negative results may occur for heparin-induced thrombocytopenia (HIT) assays; ticagrelor does not impact PF4 antibody testing 2
• Digoxin levels: Monitor with initiation or any change in ticagrelor dose 2

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Perioperative Management

Do not discontinue ticagrelor within the first 30 days after stent placement for elective non-cardiac surgery; early cessation dramatically increases stent thrombosis, MI, and death. 1, 2

• Elective surgery: Stop ticagrelor ≥5 days before procedures with major bleeding risk 1, 2
• CABG: Discontinue ≥5 days before elective CABG 1
• Post-CABG: Resume ticagrelor as soon as hemostasis achieved to complete 12 months total DAPT 1
• Urgent surgery: If bleeding occurs, manage without discontinuing ticagrelor when possible; stopping increases cardiovascular event risk 2

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Duration of Dual Antiplatelet Therapy

The default DAPT duration is 12 months for all ACS patients who are not at high bleeding risk, regardless of ACS type, stent type, or management strategy. 1

• Standard duration: 12 months (ticagrelor + aspirin) 1
• High bleeding risk: May shorten to 6 months (PRECISE-DAPT score ≥25) 1
• Extended therapy: Consider ticagrelor 60 mg twice daily beyond 12 months in high-ischemic-risk patients who tolerated initial DAPT without bleeding 1
• Transition to monotherapy: After 1–3 months, discontinuing aspirin and continuing ticagrelor alone reduces bleeding while preserving ischemic protection 1, 5, 6

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Drug Interactions

Avoid concomitant use with strong CYP3A4 inhibitors or inducers; monitor statin-related adverse effects with simvastatin >40 mg/day, lovastatin >40 mg/day, or any dose of rosuvastatin. 2

• Strong CYP3A4 inhibitors: Contraindicated (e.g., ketoconazole, itraconazole, clarithromycin) 2
• Strong CYP3A4 inducers: Avoid (e.g., rifampin, phenytoin, carbamazepine) – reduce ticagrelor efficacy 2
• Opioids: Decrease ticagrelor exposure; consider parenteral antiplatelet agent in acute settings 2
• Statins: Simvastatin or lovastatin >40 mg/day increases statin-related adverse effects; rosuvastatin levels may increase 2
• Digoxin: Monitor levels with ticagrelor initiation or dose changes 2

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Preference Over Clopidogrel

Ticagrelor is strongly preferred over clopidogrel for all ACS patients because it provides greater reduction in cardiovascular death (4.0% vs 5.1%, P=0.001), MI (5.8% vs 6.9%, P=0.005), and all-cause mortality (4.5% vs 5.9%, P<0.001) without increasing overall major bleeding. 1, 4

• Absolute mortality benefit: 1.4% reduction in 12-month all-cause mortality 1, 4
• Faster onset: Achieves platelet inhibition within 30 minutes vs hours with clopidogrel 3, 7
• More consistent inhibition: 93–100% IPA at trough vs 77% with clopidogrel (range 11–100%) 7
• No genetic variability: Does not require hepatic activation unlike clopidogrel 1

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When to Use Clopidogrel Instead

Switch to clopidogrel when oral anticoagulation is required (triple therapy), in patients with active bleeding, very high bleeding risk, or when ticagrelor is not tolerated. 1

• Triple therapy: Clopidogrel has substantially lower bleeding risk than ticagrelor when combined with oral anticoagulation 1
• Active bleeding or high bleeding risk: Clopidogrel's less potent inhibition results in fewer bleeding events 1
• Intolerable dyspnea: Switch to clopidogrel 600 mg loading, then 75 mg daily 1
• Unavailability: Clopidogrel is acceptable when ticagrelor unavailable 1

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Critical Pitfalls to Avoid

• Never discontinue DAPT within the first month after stent placement – dramatically increases stent thrombosis, MI, and death 1, 2
• Never omit a PPI when prescribing ticagrelor-based DAPT – significantly raises GI bleeding risk 1
• Never exceed 100 mg daily aspirin with ticagrelor – higher doses reduce ticagrelor efficacy and increase bleeding 1, 2
• Never delay the loading dose – administer immediately upon ACS diagnosis before any procedure 1
• Never use with another oral P2Y12 inhibitor – contraindicated 2
• Never give to patients with history of intracranial hemorrhage – absolute contraindication 1, 2