Tenecteplase Dosing for Acute Myocardial Infarction
Tenecteplase (TNK) is administered as a single weight-based intravenous bolus over 5 seconds for patients with suspected acute myocardial infarction with ST-segment elevation. 1
Weight-Based Dosing Regimen
The dose is determined by patient weight as follows: 1, 2
- <60 kg: 30 mg (6 mL)
- 60-69 kg: 35 mg (7 mL)
- 70-79 kg: 40 mg (8 mL)
- 80-89 kg: 45 mg (9 mL)
- ≥90 kg: 50 mg (10 mL)
This weight-tiered dosing was developed based on exploratory analyses showing that 0.5-0.6 mg/kg optimizes the patency-to-bleeding relationship across patient weights. 3
Administration Details
- Route: Single intravenous bolus 1, 2
- Duration: Administer over 5 seconds 2, 3
- Timing: Greatest benefit occurs within first 12 hours of symptom onset, with maximal benefit within 2 hours 2
- Preparation: Reconstitute 50 mg vial with 10 mL Sterile Water for Injection 3
Mandatory Adjunctive Therapy
All patients receiving tenecteplase must receive: 2
Antiplatelet therapy:
- Aspirin 150-325 mg loading dose (or 80-150 mg IV if oral not possible), then 75-100 mg daily 2
- Clopidogrel 300 mg loading dose (if age ≤75 years), then 75 mg daily 2
- For patients >75 years: No clopidogrel loading dose, start 75 mg daily 2
Anticoagulation (choose one):
- Enoxaparin (preferred): 2
- Age <75 years: 30 mg IV bolus, then 1 mg/kg subcutaneous every 12 hours
- Age ≥75 years: No IV bolus, 0.75 mg/kg subcutaneous every 12 hours
- Unfractionated heparin: 60 U/kg IV bolus (max 4000 U), then 12 U/kg/hour infusion (max 1000 U/hour) for 24-48 hours 2
Absolute Contraindications
Do not administer tenecteplase if any of the following are present: 1, 2
- Any prior intracranial hemorrhage
- Known structural cerebral vascular lesion or malignant intracranial neoplasm
- Ischemic stroke within 3 months (except acute ischemic stroke)
- Suspected aortic dissection
- Active bleeding or bleeding diathesis (excluding menses)
- Significant closed-head or facial trauma within 3 months
- Intracranial or intraspinal surgery within 2 months
- Severe uncontrolled hypertension (SBP >180 mmHg or DBP >110 mmHg unresponsive to therapy)
Post-Administration Management
All patients must be transferred to a PCI-capable center following fibrinolysis. 2 The timing of angiography depends on reperfusion success:
- Successful fibrinolysis: Routine angiography 3-24 hours post-administration in stable patients 2
- Failed fibrinolysis: Emergency angiography immediately if <50% ST-segment resolution at 60-90 minutes 2
Clinical Context
Tenecteplase is indicated when primary PCI cannot be performed within 120 minutes of first medical contact. 2 In the ASSENT-2 trial of 16,949 patients, tenecteplase demonstrated equivalent 30-day mortality to alteplase (approximately 6.2%) with reduced noncerebral bleeding (26.43% vs 28.95%). 4 The single-bolus administration offers significant workflow advantages over alteplase's 90-minute infusion. 1, 5
Critical pitfall: Do not use tenecteplase as facilitated therapy before planned primary PCI, as the ASSENT-4 PCI trial showed increased mortality (6.7% vs 4.9%) and worse composite outcomes when tenecteplase was given prior to PCI. 3