antithrombin (recombinant) [IV]

Adult Dosing

Thromboembolic events in hereditary antithrombin deficient patients

Pregnant patients, peri-partum

Loading dose: (100 - baseline AT activity level)/1.3 x Body Weight (kg)
Maintenance dose: (100 - baseline AT activity level)/5.4 x Body Weight (kg)

Thromboembolic events in hereditary antithrombin deficient patients

Surgical Patients, peri-operative

Loading dose: (100 - baseline AT activity level)/2.3 x Body Weight (kg)
Maintenance dose: (100 - baseline AT activity level)/10.2 x Body Weight (kg)

Dose adjustments according to AT activity

Monitoring time, 2 hrs after treatment start

If AT level <80%: Increase dose by 30%; recheck AT levels 2 hrs after each dose adjustment
If AT level 80%-120%: No dose adjustment; recheck AT levels 6 hrs after treatment start or dose adjustment
If AT level >120%: Decrease dose by 30%; recheck AT levels 2 hrs after each dose adjustment

Notes

Individualize dose based on pre-treatment AT activity level; start therapy prior to delivery or 24 hrs prior to surgery
Maintain AT activity levels between 80%-120% of normal (0.8-1.2 IU/mL)
Administer loading dose as a 15-min IV infusion immediately followed by continuous infusion of the maintenance dose
Continue treatment until anticoagulation is established
Monitor AT levels once or twice/day

Pediatric Dosing

Safety and effectiveness in pediatric patients have not been established

[Outline]

Adult Dosing
Pediatric Dosing

Indications ⬆ ⬇

Prevention of peri-operative and peri-partum thromboembolic events in hereditary antithrombin deficient patients
Note: Not Indicated for treatment of thromboembolic events in hereditary antithrombin deficient patients

Contraindications ⬆ ⬇

Hypersensitivity to any of the ingredients of the product
Hypersensitivity to goat and goat milk proteins

Black Box Warnings ⬆ ⬇

Dosing Adjustment ⬆ ⬇

Renal Dose Adjustment

Renal impairment: Dose adjustments not defined

Hepatic Dose Adjustment

Hepatic impairment: Dose adjustments not defined

Warnings/Precautions ⬆ ⬇

See Supplemental Patient Information

Hypersensitivity reactions including hives, generalized urticaria, tightness of the chest, wheezing, hypotension, and anaphylaxis may occur during infusion period. Discontinue therapy if anaphylaxis and severe hypersensitivity reactions occur and administer emergency treatment
Addition or withdrawal of the antithrombin [recombinant] may alter the anticoagulation activity of other drugs containing antithrombin
Perform aPTT and anti-Factor Xa activity, at close intervals, especially in the first hours following the start or withdrawal of the therapy. Monitor patients for bleeding or thrombosis
Appropriately make dose adjustments by monitoring AT activity once or twice/day

Supplemental Patient Information

Inform patients about the risk of bleeding when antithrombin(recombinant) is administered with other anticoagulants and instruct them to notify their physicians of any bleeding events while on treatment

Pregnancy/Breast Feeding ⬆ ⬇

Pregnancy Category:C

Breastfeeding: Antithrombin is excreted in breastmilk at levels of 1/50 to 1/100 of its concentration in the blood, which is same as estimated to be present in breast milk of normal lactating women, which is not harmful to breastfed neonates. However use cautiously in nursing woman if benefit outweigh the risks.

Adverse Reactions ⬆ ⬇

CV: Hematoma, flushing, chest pain, tightness of chest, hypotension
RESP: Wheezing
GI: Intra-abdominal hemorrhage
GU: Hematuria
DERM: Hives, generalized urticaria
HEPA: Abnormal hepatic enzymes, abnormal LFTs
MUSC: Hemarthrosis
LOCAL: Infusion-site reactions, application-site pruritus
MISC: Hemorrhage, anaphylaxis

Clinical Pharmacology ⬆ ⬇

Anticoagulant; inhibits thrombin and Factor Xa activity by forming a complex that leads to anticoagulation
Metabolism: Unknown; CYP450: Unknown
Excretion: Unknown
Half-life: 11.6-17.7 hrs

Brands and Availability ⬆ ⬇