Skip to Content

Factor XIII A-Subunit (Recombinant)

Medically reviewed on Nov 15, 2018


(FAK ter THIR teen aye SUB yoo nit ree KOM be nant)

Index Terms

  • Catridecacog
  • Recombinant Factor XIII A-Subunit
  • rFXIII

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Solution Reconstituted, Intravenous:

Tretten: 2000 - 3125 units (1 ea)

Brand Names: U.S.

  • Tretten

Pharmacologic Category

  • Antihemophilic Agent


Factor XIII A-Subunit (recombinant) is a protransglutaminase (rFXIII [rA2] homodimer) and binds to free human FXIII B-subunit resulting in a heterotetramer [rA2B2]. rFXIII has been shown to be activated by thrombin in the presence of Ca2+. Activated rFXIII has been shown in dose-dependent manner to increase mechanical strength of fibrin clots, retard fibrinolysis, and rFXIII has been shown to enhance platelet adhesion to the site of injury. After combining with available plasma B-subunits, factor XIII A-subunit (recombinant) has been shown to have the same pharmacodynamic properties in plasma as endogenous FXIII.


Vss: ~61–66 mL/kg

Half-Life Elimination

Children (<6 years): ~7 days; Children (≥7 years) and Adults ~ 5 days

Use: Labeled Indications

Factor XIII A-subunit deficiency: Routine prophylaxis of bleeding in patients with congenital factor XIII A-subunit deficiency


Hypersensitivity to the active substance or any component of the formulation

Dosing: Adult

Factor XIII A-subunit deficiency: IV: 35 units/kg once monthly to achieve a target trough level of factor XIII activity ≥10% using a validated assay; consider dose adjustment if adequate coverage is not achieved (higher doses may not increase the levels of tetrameric factor XIII). Note: Treatment should be initiated under the supervision of a healthcare provider experienced in the treatment of rare bleeding disorders.

Dosing: Geriatric

Refer to adult dosing.

Dosing: Pediatric

Infants, Children, and Adolescents: Refer to adult dosing.

Dosing: Renal Impairment

No dosage adjustment provided in manufacturer’s labeling.

Dosing: Hepatic Impairment

No dosage adjustment provided in manufacturer’s labeling.


Bring the vial of powder and diluent to room temperature, but not above 25°C (77°F). Reconstitute only with 3.2 mL sterile water (provided); do not inject the diluent directly on the powder to avoid foaming. Gently swirl; do not shake. After reconstitution, each vial contains 667-1042 units/mL recombinant coagulation factor XIII A-subunit. For smaller dose that requires less than the full volume in the vial, reconstituted solution may be diluted with sodium chloride 0.9% to facilitate measurement of small volumes; discard remaining product. Use immediately (or may store at room temperature not to exceed 25°C (77°F) for up to 3 hours).


IV: Administer IV only at a rate not exceeding 1 to 2 mL/minute. Do not administer with other infusion solutions. Do not administer as drip.


Prior to reconstitution, store refrigerated at 2°C to 8°C (36°F to 46°F). Do not freeze; protect from light. If the reconstituted solution is not used immediately, store refrigerated or at room temperature not to exceed 25°C (77°F) for up to 3 hours; discard after 3 hours.

Drug Interactions

Factor VIIa (Recombinant): Factor XIII A-Subunit (Recombinant) may enhance the thrombogenic effect of Factor VIIa (Recombinant). Monitor therapy

Adverse Reactions

1% to 10%:

Central nervous system: Headache (≥1%)

Hematologic & oncologic: Increased fibrinolysis (increase in fibrin D dimer levels; ≥1%)

Immunologic: Antibody development (non-neutralizing; 2% to 5%)

Local: Pain at injection site (≥1%)

Neuromuscular & skeletal: Limb pain (≥1%)


Concerns related to adverse effects:

• Antibody formation: Inhibitory antibodies may occur. Patients with inhibitory antibodies may manifest as an inadequate response to treatment. Factor XIII inhibitory antibodies should be measured when breakthrough bleeding or factor XIII activity levels are suboptimal after apparent adequate dosing.

• Hypersensitivity reactions: May cause allergic reactions; discontinue immediately if signs or symptoms of anaphylaxis or hypersensitivity reactions (including urticaria, rash, tightness of the chest, wheezing, hypotension) occur and institute appropriate management.

• Thrombotic events: Thromboembolic complications may occur; monitor patients with known risk factors for thrombosis.

Other Warnings/Precautions:

• Appropriate use: Not indicated for use in patients with congenital factor XIII B-subunit deficiency.

Monitoring Parameters

Factor XIII trough levels in conjunction with clinical response to assess efficacy; factor XIII inhibitory antibodies if inadequate clinical response and/or factor XIII trough levels are suboptimal; signs/symptoms of hypersensitivity reactions, and thrombotic events.

Pregnancy Considerations

Pregnant patients with factor XIII deficiency may have an increased risk of bleeding following abortion, antenatal procedures, and delivery. There is also a high rate of pregnancy loss without treatment; close surveillance is recommended. Maternal factor XIII concentrations decrease during pregnancy and dosing frequency should be increased. Additional treatment may be needed prior to delivery or procedures. Factor XIII A-Subunit (Recombinant) may be used in patients with a factor XIII A-subunit deficiency (RCOG [Pavord 2017]).

Patient Education

• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)

• Patient may experience headache, leg pain, arm pain, or injection site irritation. Have patient report immediately to prescriber signs of severe cerebrovascular disease (change in strength on one side is greater than the other, difficulty speaking or thinking, change in balance, or vision changes), signs of DVT (edema, warmth, numbness, change in color, or pain in the extremities), shortness of breath, dizziness, passing out, angina, coughing up blood, bruising, or bleeding (HCAHPS).

• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for healthcare professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience and judgment in diagnosing, treating and advising patients.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.