How to dilute tenecteplase (TNK-tPA) for intravenous (IV) administration?

Tenecteplase (TNK-tPA) Dilution for Intravenous Administration

Tenecteplase should be reconstituted by adding 10 mL of Sterile Water for Injection to the vial containing the lyophilized powder, resulting in a concentration of 5 mg/mL, and administered as a single intravenous bolus over 5 seconds based on patient weight. 1

Preparation Process

Step 1: Reconstitution

• Using a sterile syringe, aseptically withdraw 10 mL of Sterile Water for Injection, USP, from the supplied diluent vial
• Only use the supplied Sterile Water for Injection, USP for reconstitution
• Direct the stream into the lyophilized powder to obtain a final concentration of 5 mg/mL
• Slight foaming upon reconstitution is not unusual; allow the product to stand undisturbed for several minutes for large bubbles to dissipate
• Gently swirl until contents are completely dissolved - DO NOT SHAKE
• The reconstituted preparation should result in a colorless to pale yellow transparent solution 1

Step 2: Dose Calculation

Determine the appropriate dose based on patient weight:

• < 60 kg: 30 mg (6 mL)
• ≥ 60 to < 70 kg: 35 mg (7 mL)
• ≥ 70 to < 80 kg: 40 mg (8 mL)
• ≥ 80 to < 90 kg: 45 mg (9 mL)
• ≥ 90 kg: 50 mg (10 mL) 1

Step 3: Withdrawal and Administration

• Withdraw the calculated volume (in milliliters) from the reconstituted vial with a syringe
• Inspect the product prior to administration for particulate matter and discoloration
• Connect the syringe directly to the intravenous port using sterile technique
• Administer as a single intravenous bolus over 5 seconds 1

Important Considerations

Chemical Incompatibilities

• Tenecteplase is incompatible with dextrose-containing solutions
• Precipitation may occur when tenecteplase is administered in an intravenous line containing dextrose
• Flush dextrose-containing lines with 0.9% sodium chloride, USP, solution prior to and following single bolus administration of tenecteplase 1

Storage of Reconstituted Solution

• Because tenecteplase contains no antibacterial preservatives, reconstitute immediately before use
• If not used immediately, refrigerate the reconstituted tenecteplase vial at 2°C to 8°C (36°F to 46°F)
• Use within 8 hours of reconstitution 1

Clinical Context

• Tenecteplase is indicated to reduce the risk of death associated with acute ST elevation myocardial infarction (STEMI) 1
• It is administered as a single weight-adjusted intravenous bolus, making it the most convenient option in the pre-hospital setting 2
• The combination of tenecteplase, enoxaparin, aspirin, and clopidogrel is the most widely studied and validated within the pharmaco-invasive strategy 2

Pharmacokinetic Advantages

• Tenecteplase has a longer half-life (22 minutes initial half-life) compared to alteplase (3.5 minutes), allowing for single-bolus administration 3
• It exhibits biphasic disposition with a mean terminal half-life of 65-132 minutes 3
• The mean clearance is approximately 105 mL/min over the clinically relevant dose range of 30-50 mg 4

By following these specific dilution and administration instructions, you can ensure proper delivery of tenecteplase for patients requiring thrombolytic therapy.