Congenital fibrinogen deficiency: IV: Note: Maintain a target fibrinogen level of 100 mg/dL for minor bleeding and 150 mg/dL for major bleeding.
When baseline fibrinogen level is known:
Fibryga: Dose (mg/kg) = [Target level (mg/dL) - measured level (mg/dL)] divided by 1.8 (mg/dL per mg/kg body weight)
RiaSTAP: Dose (mg/kg) = [Target level (mg/dL) - measured level (mg/dL)] divided by 1.7 (mg/dL per mg/kg body weight)
When baseline fibrinogen level is not known: 70 mg/kg
There are no dosage adjustments provided in the manufacturer's labeling.
There are no dosage adjustments provided in the manufacturer's labeling.
(For additional information see "Fibrinogen, concentrate from human plasma: Pediatric drug information")
Note: Dosing must be individualized for each patient based on the extent of bleeding, laboratory values, clinical condition of the patient, and target fibrinogen concentration.
Congenital fibrinogen deficiency; treatment of acute bleeding: Note: The recommended target fibrinogen concentration is 100 mg/dL for minor bleeding and 150 mg/dL for major bleeding.
Initial dose:
When baseline fibrinogen concentration is known:
RiaSTAP: Infants, Children, and Adolescents (Kreuz 2005; Manco-Johnson 2009; RiaSTAP prescribing information [UK] 2016): IV:
Dose (mg/kg) = [Target fibrinogen concentration (mg/dL) – measured fibrinogen concentration (mg/dL)] divided by 1.7 (mg/dL per mg/kg body weight)
Fibryga:
Children <12 years: IV:
Dose (mg/kg) = [Target fibrinogen concentration (mg/dL) – measured fibrinogen concentration (mg/dL)] divided by 1.4 (mg/dL per mg/kg body weight)
Children ≥12 years and Adolescents: IV:
Dose (mg/kg) = [Target fibrinogen concentration (mg/dL) – measured fibrinogen concentration (mg/dL)] divided by 1.8 (mg/dL per mg/kg body weight)
When baseline fibrinogen level is not known: Fibryga, RiaSTAP: Infants, Children, and Adolescents: IV: 70 mg/kg.
Repeat doses: Adjust dose based on laboratory values and condition of patient. Administer additional doses if the fibrinogen concentration falls below 80 mg/dL for minor bleeding and below 130 mg/dL for major bleeding until hemostasis is achieved.
There are no dosage adjustments provided in manufacturer's labeling.
There are no dosage adjustments provided in manufacturer's labeling.
Refer to adult dosing.
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Injection, powder for reconstitution:
Fibryga: ~1 g [exact potency labeled on vial]
RiaSTAP: 900-1300 mg [contains albumin (human); exact potency labeled on vial]
No
Strengths expressed with approximate values. Consult individual vial labels for exact potency within each vial.
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Injection, powder for reconstitution:
Fibryga: ~1 g [exact potency labeled on vial]
RiaSTAP: 900-1300 mg [contains albumin (human); exact potency labeled on vial]
IV: For IV administration only; infuse at a rate not exceeding 5 mL/minute. Solution should be infused at room temperature. Do not administer with other products or IV solutions. Administration should be completed within 8 hours (RiaSTAP) or 4 hours (Fibryga) after reconstitution. For RiaSTAP, filter reconstituted solution with a 17-micron filter (not supplied) into an appropriate syringe before administration. For Fibryga, filter reconstituted solution with the supplied 17-micron particle filter into an appropriate syringe before administration.
IV: For IV administration only. Infuse slowly at ≤5 mL/minute. Solution should be infused at room temperature. Do not administer with other products or IV solutions. Administrations should be completed within 4 hours (Fibryga) or 8 hours (RiaSTAP) after reconstitution.
Congenital fibrinogen deficiency: Treatment of acute bleeding episodes in pediatric and adult patients with congenital fibrinogen deficiency, including afibrinogenemia and hypofibrinogenemia.
The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified.
1% to 10%:
Gastrointestinal: Nausea (>5%), vomiting (>5%)
Hematologic: Thrombocythemia (>5%)
Nervous system: Headache (>1%)
Miscellaneous: Fever (>1%)
Frequency not defined:
Cardiovascular: Ischemia (digital foot), peripheral thrombophlebitis (upper limbs), portal vein thrombosis (following splenectomy)
Dermatologic: Erythema of skin, pruritus
Postmarketing:
Cardiovascular: Acute myocardial infarction, arterial thrombosis, deep vein thrombosis, pulmonary embolism, thromboembolism, thrombosis
Dermatologic: Skin rash
Hypersensitivity: Anaphylaxis, hypersensitivity reaction
Nervous system: Chills
Respiratory: Dyspnea
Severe, immediate hypersensitivity reactions, including anaphylaxis to fibrinogen, human plasma-derived products, or any component of the formulation.
Concerns related to adverse effects:
• Hypersensitivity: Hypersensitivity reactions (eg, hives, generalized urticaria, chest tightness, wheezing, hypotension, anaphylaxis) may occur. In the event of hypersensitivity reactions, treatment should be discontinued immediately.
• Thrombotic events: Thrombosis may occur spontaneously in patients with congenital fibrinogen deficiency with or without fibrinogen replacement therapy. Thromboembolic events have been reported in patients receiving fibrinogen concentrate. Consider potential risk of thrombosis with use; monitor for signs and symptoms of thrombosis.
Dosage form specific issues:
• Human plasma: Product of human plasma; may potentially contain infectious agents which could transmit disease (eg, viruses and theoretically the Creutzfeldt-Jakob disease [CJD]). Screening of donors, as well as testing and/or inactivation or removal of certain viruses, reduces the risk. Infections thought to be transmitted by this product should be reported to the manufacturer.
Other warnings/precautions:
• Appropriate use: Not indicated for the treatment of dysfibrinogenemia.
None known.
There are no known significant interactions.
Patients with congenital fibrinogen deficiency may have an increased risk of bleeding, thrombosis, and pregnancy loss; replacement therapy may be initiated prior to conception (RCOG [Pavord 2017]).
Pregnant patients with congenital fibrinogen deficiency may have an increased risk of bleeding, thrombosis, and pregnancy loss; therefore, close surveillance is recommended. Maternal fibrinogen concentrations increase during pregnancy but do not protect against potential complications. Prophylaxis throughout pregnancy may be needed and higher doses may be required as pregnancy progresses. Plasma derived fibrinogen concentrate may be used for treatment or prevention of bleeding in patients with severe deficiency (RCOG [Pavord 2017]).
According to the manufacturer, the decision to continue or discontinue breastfeeding during therapy should take into account the risk of infant exposure, the benefits of breastfeeding to the infant, and benefits of treatment to the mother.
Fibrinogen level; signs/symptoms of hypersensitivity and thrombosis
A target fibrinogen level of 100 mg/dL should be maintained until hemostasis occurs and wound healing is complete.
Normal fibrinogen levels: 200 to 450 mg/dL
Fibrinogen (coagulation factor I), a protein found in normal plasma, is required to clot blood. Fibrinogen concentrate made from pooled human plasma replaces this protein which is missing or reduced in patients with a congenital fibrinogen deficiency.
Note: In pediatric patients (12 to 17 years of age) receiving Fibryga, pharmacokinetic values were reported to be similar to adult data.
Distribution: Vd:
Fibryga:
Patients <6 years of age: 68.6 ± 4.4 mL/kg (range: 63.9 to 72.7 mL/kg).
Patients 6 to <12 years of age: 67.2 ± 8.2 mL/kg (range: 52.8 to 76.8 mL/kg).
Patients ≥12 years of age (including adults): 70.2 ± 29.9 mL/kg (range: 36.9 to 149.1 mL/kg).
RiaSTAP: Patients 8 to 61 years of age: 52.7 ± 7.48 mL/kg (range: 36.22 to 67.67 mL/kg).
Half-life elimination: Similar to biological fibrinogen.
Biological fibrinogen: 100 hours (Kamath 2003).
Fibryga:
Patients <6 years of age: 56.9 ± 10.8 hours (range: 45.6 to 67 hours).
Patients 6 to <12 years of age: 66.1 ± 12.1 hours (range: 57.7 to 91.6 hours).
Patients ≥12 years of age (including adults): 75.9 ± 23.8 hours (range: 40 to 157 hours).
RiaSTAP:
Patients <16 years of age: 69.9 ± 8.54 hours.
Patients ≥16 years of age: 82.3 ± 20.04 hours.
Excretion:
Clearance:
Fibryga:
Patients <6 years of age: 0.9 ± 0.1 mL/hour/kg (range: 0.8 to 1 mL/hour/kg).
Patients 6 to <12 years of age: 0.7 ± 0.1 mL/hour/kg (range: 0.5 to 0.9 mL/hour/kg).
Patients ≥12 years of age (including adults): 0.7 ± 0.2 mL/hour/kg (range: 0.4 to 1.2 mL/hour/kg).
RiaSTAP: Patients 8 to 61 years of age: 0.59 ± 0.13 mL/hour/kg (range: 0.45 to 0.86 mL/hour/kg); subgroup analysis showed faster clearance in subjects <16 years of age.