Transfusion medicine handbook

5. Fractionated Products

5.1.5 FIBROGAMMIN (Factor XIII)

Fibrogammin does not have full New Zealand registration and so consultation with an NZBS Transfusion Medicine Specialist/ Medical Officer is required prior to product release. It is supplied by NZBS under Section 29, a provision in the Medicines Act 1981, whereby a medical practitioner can prescribe a medicine that is not registered with Medsafe. The Summary of Product Characteristics from the UK is available at https://www.medicines.org.uk/emc/medicine/405 .

Fibrogammin is a freeze-dried powder of purified human factor XIII. Each vial when reconstituted contains 250 IU factor XIII.

Indications for Use

Fibrogammin is indicated for adult and paediatric patients.

Congenital deficiency of Factor XIII and resultant haemorrhagic diathesis, haemorrhages and disturbances in wound healing.

Dosage and Administration

The dosing regimen should be individualised based on body weight, laboratory values, and the patient's clinical condition.

The following guideline is to assist in the immediate management of a patient until consultation with a specialist haematologist or NZBS Transfusion Medicine Specialist/ Medical Officer.

Routine prophylaxis dosing schedule for treatment of congenital FXIII deficiency

Initial dose

• 40 IU per kg body weight.
• The injection rate should not exceed 4 mL per minute.

Subsequent dosing

• Dosing should be guided by the most recent trough FXIII activity level, with dosing every 28 days (4 weeks) to maintain a trough FXIII activity level of approximately 5 to 20%.
• Recommended dosing adjustments of ± 5 IU per kg should be based on trough FXIII activity levels and the patient's clinical condition.
• Dosing adjustments should be made on the basis of a specific, sensitive assay used to determine FXIII levels.

Prophylaxis prior to surgery

After the patient's last routine prophylactic dose, if surgery is scheduled:

• Between 21 and 28 days later – administer the patient's full prophylaxis dose immediately prior to surgery and the next prophylactic dose should be given 28 days later.
• Between 8 and 21 days later – an additional dose (full or partial) may be administered prior to surgery. The dose should be guided by the patient's FXIII activity levels and clinical condition and should be adjusted according to the half-life of Fibrogammin.
• Within 7 days of last dose – additional dosing may not be needed.

Adjustments to dosing may be different from these recommendations and should be individualised, based on FXIII activity levels and the patient's clinical condition. All patients should be monitored closely during and after surgery.

It is recommended to monitor the increase in FXIII-activity with a FXIII assay. In the case of major surgery and severe haemorrhage, the aim is to obtain values within the normal range for healthy people, i.e., 0.7 -1.4 IU/mL.

Precautions

• Allergic reactions
  If symptoms of hypersensitivity (such as hives, generalised urticaria, tightness of the chest, wheezing, hypotension, and anaphylaxis) occur, the Fibrogammin infusion should be discontinued.
• Antibodies to factor XIII
  Patients with congenital deficiency may rarely develop neutralising alloantibodies (inhibitors) to factor XIII after repeated treatment.
• Thrombosis
  In cases of fresh thrombosis caution should be exercised due to the fibrin-stabilising effect.

Note for diabetic patients:

Fibrogammin contains glucose (24 mg per 250 IU). When administering a dose of 40 IU/kg body weight to a patient with 75 kg body weight, a maximum of 288 mg glucose will be supplied.