Dosing and uses of TNK tPA, TNKase (tenecteplase)
Adult dosage forms and strengths
powder for injection
- 50mg
Acute MI
Administer ASAP (within 30 minutes) after onset of acute MI
30-50 mg IV bolus over 5 sec once (based on weight)
- <60 kg: 30 mg
- 60-70 kg: 35 mg
- 70-80 kg: 40 mg
- 80-90 kg: 45 mg
- >90 kg: 50 mg
Restore Function to Hemodialysis Catheters (Orphan)
Indicated to estore function to hemodialysis catheters
Orphan indication sponsor
- Genentech, Inc; 1 DNA Way; South San Francisco, CA 94080-4990
Pediatric dosage forms and strengths
Safety & efficacy not established
TNK tPA, TNKase (tenecteplase) adverse (side) effects
>10%
Minor bleeding (22%)
Frequency not defined
Reperfusion arrhythmias
MI
Fever
Nausea
Vomiting
Cholesterol embolization
Allergic reaction
Warnings
Contraindications
Hypersensitivity
Active bleeding, history of CVA, recent (within 2 months) intracranial or intraspinal surgery or trauma, intracranial neoplasm, AVM, aneurysm, bleeding diathesis, severe uncontrolled HTN, recent (within 3 mth) facial trauma, suspected aortic dissection
See thrombolytic indications/contraindications
Cautions
Recent major surgery, cerebrovascular disease, recent GI or GU bleeding, HTN, acute pericarditis, subacute endocarditis, hemostatic defects, high likelihood of left heart thrombus, severe thrombophlebitis, severe hepatic/renal dysfunction, currently receiving oral anticoagulants, diabetic hemorrhagic retinopathy, elderly, recent admin of GP IIb/IIIa inhibitors
Acute pericarditis, subacute endocarditis
Ischemic Stroke: may have no benefit if used after 3 hr of onset
Current use of warfarin and INR in high range may increase bleeding risk
Monitor potential bleeding sites
Cholesterol embolism reported
Pregnancy or breastfeeding
Adjuncts for MI treatment
Pregnancy and lactation
Pregnancy category: C
Lactation: not known whether drug crosses into breast milk, nursing not a priority in AMI
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of TNK tPA, TNKase (tenecteplase)
Mechanism of action
Genetically engineered variant of alteplase with multiple point mutations of tPA molecule resulting in longer plasma half-life, enhanced fibrin specificity, & increased resistance to inactivation by plasminogen activator inhibitor 1 (PAI-1) compared to alteplase
Promotes thrombolysis by converting plasminogen to plasmin which degrades fibrin & fibrinogen
Pharmacokinetics
Half-Life: 90-130 min
Onset: 30 min
Metabolism: Liver
Metabolites: Degradation products (constituent amino acids of tenecteplase)
Total Body Clearance: 99-119 mL/min
Administration
IV Preparation
Add 10 mL SWI to a 50 mg vial using TwinPak® device directing stream of diluent into powder. If foaming (usually slight) occurs, leave vial undisturbed for several minutes to allow dissipation of any large bubbles. Gently swirl (do not shake) until contents are completely dissolved.
Do not discard shield assembly
Use immediately or may be refrigerated up to 8 hr