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Antihemophilic Factor (Recombinant [Porcine Sequence])

Medically reviewed by Drugs.com. Last updated on Oct 5, 2020.

Pronunciation

(an tee hee moe FIL ik FAK tor ree KOM be nant POR sine SEE kwens)

Index Terms

  • AHF (Recombinant [Porcine Sequence])
  • Factor VIII (Recombinant [Porcine Sequence])
  • pFVIII
  • rAHF
  • rpFVIII
  • Susoctocog Alfa

Dosage Forms

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

Solution Reconstituted, Intravenous:

Obizur: 500 units (1 ea) [contains polysorbate 80]

Brand Names: U.S.

  • Obizur

Pharmacologic Category

  • Antihemophilic Agent

Pharmacology

Factor VIII replacement, necessary for clot formation and maintenance of hemostasis, activates factor X in conjunction with activated factor IX. Activated factor X converts prothrombin to thrombin, which converts fibrinogen to fibrin, and with factor XIII forms a stable clot.

Use: Labeled Indications

Acquired hemophilia A: Treatment of bleeding episodes in adults with acquired hemophilia A

Limitations of use: Not indicated for the treatment of congenital hemophilia A or von Willebrand disease; safety and efficacy of has not been established in patients with baseline anti- porcine factor VIII inhibitor titer >20 BU.

Off Label Uses

Congenital hemophilia A

Data from a small prospective, multicenter, open-label, phase 2 trial suggests that antihemophilic factor (recombinant [porcine sequence]) replacement therapy may be efficacious as an alternative to bypassing agents for the treatment of bleeding episodes in patients with congenital hemophilia A and factor VIII inhibitors [Mahlangu 2017].

Contraindications

Life-threatening hypersensitivity reactions to antihemophilic factor (recombinant [porcine sequence]) or any component of the formulation (including traces of hamster proteins).

Dosing: Adult

Acquired hemophilia A: IV: Note: Dose, dosing frequency, and duration based on location and severity of bleeding, target factor VIII levels, and clinical condition of the patient. Plasma levels of factor VIII should not exceed 200% of normal or 200 units/dL. Patients with inhibitory antibodies to recombinant porcine factor VIII may require higher doses and/or more frequent administration than patients without inhibitory antibodies (Kruse-Jarres 2015).

Minor to moderate hemorrhage: 200 units/kg initially to achieve factor VIII plasma level 50% to 100% of normal; titrate subsequent doses to maintain recommended factor VIII trough levels and individual clinical response; dose every 4 to 12 hours (frequency may be adjusted based on clinical response/factor VIII levels).

Major hemorrhage: 200 units/kg initially to achieve factor VIII plasma level 100% to 200% (for acute bleed) or 50% to 100% (after acute bleed is controlled, if required) of normal; titrate subsequent doses to maintain recommended factor VIII trough levels and individual clinical response; dose every 4 to 12 hours (frequency may be adjusted based on clinical response/factor VIII levels).

Off-label dosing: Based on limited data: 100 units/kg initially; titrate subsequent doses and dosing interval to maintain targeted peak and trough levels based on individual clinical response; refer to protocols for details (Martin 2016; Stemberger 2016; Tarantino 2017).

Congenital hemophilia A (off-label use): Based on limited data: IV: Initial: 200 units/kg; titrate subsequent doses based on factor VIII activity levels and individual clinical response (Mahlangu 2017). Note: Loading doses used in this protocol varied based on the level of porcine factor VIII inhibitor levels (refer to protocol for further details); however, the authors concluded that a 200 units/kg loading dose is more clinically feasible (Mahlangu 2017).

Dosing: Geriatric

Refer to adult dosing.

Dosing: Obesity

There are insufficient data to recommend specific dose adjustments for overweight and obese patients. Some experts use ideal body weight in dosing calculations or actual body weight and a correction factor, then adjust dose as necessary based on clinical response (Henrard 2013; McEneny-King 2017; Tiede 2019).

Reconstitution

Allow vial and diluent to warm to room temperature before reconstitution. Gently swirl vial in a circular motion after adding diluent until dissolved.

Administration

IV: Administer IV at a rate of 1 to 2 mL/minute. Do not administer in the same tubing or container with other medications.

Storage

Store refrigerated at 2°C to 8°C (36°F to 46°F). Do not freeze. Store the original package to protect from light. Use within 3 hours after reconstitution; discard any unused solution if not used within 3 hours after reconstitution.

Drug Interactions

There are no known significant interactions.

Adverse Reactions

The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified.

>10%: Immunologic: Antibody development (26%)

Frequency not defined: Hypersensitivity: Hypersensitivity reaction

Postmarketing: Hematologic & oncologic: Increased factor VIII inhibitors (anamnestic reaction)

Warnings/Precautions

Concerns related to adverse effects:

• Antibody formation: Formation of antiporcine factor VIII antibodies has occurred; monitor patients for the development of antibodies. Suspect an antiporcine factor VIII antibody if the plasma factor VIII level does not increase as expected or if bleeding is not controlled after administration. Anamnestic reactions with rise in human factor VIII inhibitors and/or porcine factor VIII inhibitors have been reported and may result in a lack of response to antihemophilic factor. If inhibitory antibodies are suspected and there is a lack of clinical response, consider other therapy.

• Hypersensitivity reactions: May occur; discontinue immediately if allergic or anaphylactic-type reactions occur.

Dosage form specific issues:

• Hamster protein: May contain trace amounts of hamster proteins.

• Polysorbate 80: Some dosage forms may contain polysorbate 80 (also known as Tweens). Hypersensitivity reactions, usually a delayed reaction, have been reported following exposure to pharmaceutical products containing polysorbate 80 in certain individuals (Isaksson 2002; Lucente 2000; Shelley 1995). Thrombocytopenia, ascites, pulmonary deterioration, and renal and hepatic failure have been reported in premature neonates after receiving parenteral products containing polysorbate 80 (Alade 1986; CDC 1984). See manufacturer’s labeling.

• Sucrose: May contain sucrose.

Other warnings/precautions:

• Dose requirements: The dosage requirement will vary in patients with factor VIII inhibitors; optimal treatment should be determined by clinical response.

Monitoring Parameters

Heart rate and blood pressure (before and during IV administration); plasma factor VIII activity prior to and during treatment (30 minutes and 3 hours after initial dose; 30 minutes after subsequent doses); development of factor VIII inhibitors or presence of cross-reacting antibodies; signs of bleeding; hemoglobin, hematocrit.

Pregnancy Considerations

Pregnant hemophilia A carriers may have an increased bleeding risk following abortion, invasive procedures, miscarriage, and delivery; close surveillance is recommended. Factor VIII levels should be monitored at the first antenatal visit, once or twice during the third trimester, prior to surgical or invasive procedures, and at delivery. Although factor VIII concentrations increase in pregnant patients, factor VIII replacement is recommended if concentrations are <0.5 IU/mL and any of the following occur: need for invasive procedures (including delivery), spontaneous miscarriage, insertion and removal of epidural catheters, or active bleeding. Hemostatic factor VIII concentrations should be maintained for at least 3 to 5 days following invasive procedures or postpartum. If replacement with a factor VIII concentrate product is indicated, a recombinant product is preferred (NHF 2017; RCOG [Pavord 2017]; WFH [Srivastava 2013]).

Patient Education

What is this drug used for?

• It is used to treat bleeding in people with a type of hemophilia A.

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Dizziness

• Passing out

• Shortness of breath

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.

Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.

Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a limited summary of general information about the medicine's uses from the patient education leaflet and is not intended to be comprehensive. This limited summary does NOT include all information available about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not intended to provide medical advice, diagnosis or treatment and does not replace information you receive from the healthcare provider. For a more detailed summary of information about the risks and benefits of using this medicine, please speak with your healthcare provider and review the entire patient education leaflet.

Further information

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

Frequently Asked Questions