Transfusion medicine handbook

5. Fractionated Products

5.4.12 GAMUNEX 10%

Gamunex 10%, a commercial lVIg produced from paid donor plasma. It is primarily used for patients who do not tolerate Privigen NZ or Privigen. 

Indications for use

Replacement therapy in:

• Primary Immunodeficiency (PI) diseases.
• Symptomatic Hypogammaglobulinaemia secondary to underlying disease or treatment.

Immunomodulation in:

• Idiopathic Thrombocytopenic Purpura (ITP), in patients at high risk of bleeding or prior to surgery to correct the platelet count.
• Guillain Barré Syndrome (GBS).
• Chronic Inflammatory Demyelinating Polyneuropathy (CIDP).
• Kawasaki disease.

Dose and Administration

Gamunex 10% is recommended for administration by intravenous infusion for all indications.

Gamunex 10% should initially be infused at a rate of 0.01 mL/kg per minute (1 mg/kg per minute) for the first 30 minutes. If well-tolerated, the rate may be gradually increased to a maximum of 0.08 mL/kg per minute (8 mg/kg per minute). If side effects occur, the rate may be reduced, or the infusion interrupted until symptoms subside. The infusion may then be resumed at the rate which is comfortable for the patient [17].

Gamunex 10% can also be administered by subcutaneous infusion for replacement therapy in primary immunodeficiency indications only. Safety and efficacy of subcutaneous administration has not been demonstrated for other indications. Discussion with an NZBS Transfusion Medicine Specialist/ Medical Officer is recommended.

Replacement therapy in Primary Immunodeficiency (PI) diseases. Intravenous Gamunex 10% doses between 300 and 600 mg/kg (3 and 6 mL/kg) may be used for infection prophylaxis. The dose should be individualized taking into account dosing intervals (e.g. 3 or 4 weeks) and dose (between 300 and 600 mg/kg).

Replacement therapy in symptomatic secondary hypogammaglobulinaemia. The recommended dose is 200 to 400 mg/kg every 3 to 4 weeks, to obtain a trough level of at least 5 to 6 g/L.

Idiopathic Thrombocytopenic Purpura (ITP).  Gamunex 10% may be administered at a total dose of 2 g/kg, divided in two doses of 1 g/kg (10 mL/kg) given on two consecutive days or into five doses of 0.4 g/kg (4 mL/kg) given on five consecutive days.

Guillain Barré Syndrome (GBS). 400 mg/kg (4 mL/kg) on three to seven consecutive days. The treatment should commence within 14 days of the onset of symptoms.

Chronic Inflammatory Demyelinating Polyneuropathy (CIDP). Loading dose: 2 g/kg (20 mL/kg) in divided doses over 2 to 4 consecutive days. Maintenance dose: 1 g/kg administered over 1 day (10 mL/kg) or divided into two doses of 500 mg/kg (5 mL/kg) given on two consecutive days, every 3 weeks. Only limited experience is available of use of intravenous immunoglobulins in children with CIDP.

Kawasaki disease. 1.6 to 2 g/kg (16 to 20 mL/kg) as a single infusion or in divided doses over 2 to 5 days.

Contraindications

Gamunex 10% is contraindicated in individuals with known anaphylactic or severe systemic response to human immunoglobulin or any of the excipients of the product. This applies in particular to individuals with severe, selective IgA deficiencies (serum IgA <0.05 g/L) who have known antibodies against IgA (anti-IgA antibody), due to the risk of severe immediate hypersensitivity reactions including anaphylaxis.

Precautions

• Certain undesirable effects may be related to the rate of infusion
• Renal effects. Human normal immunoglobulin intravenous products have been reported to be associated with acute renal dysfunction, acute renal failure, acute tubular necrosis, proximal tubular nephropathy, osmotic nephrosis and death.
• Infection risk
• Anaphylaxis
• Aseptic Meningitis Syndrome. The syndrome usually begins within several hours to two days following human normal immunoglobulin intravenous treatment. It is characterized by symptoms and signs including severe headache, nuchal rigidity, drowsiness, fever, photophobia, painful eye movements, nausea and vomiting
• IV Ig products can contain blood group antibodies which may act as haemolysins and induce in vivo coating of red blood cells with immunoglobulin, causing a positive direct antiglobulin reaction and, rarely, haemolysis.
• Thrombotic events

Adverse Reactions

Incidence of frequency ≥ 1 % and < 10% (common)

• Headache
• Pyrexia

Incidence of frequency ≥ 0.1% and < 1% (uncommon)

• White blood cell count decreased
• Dizziness
• Urticaria, dermatitis, pruritus, rash
• Abdominal pain, diarrhoea, nausea, vomiting
• Hypertension, hypotension
• Pharyngitis, cough, nasal congestion, wheezing
• Arthralgia, back pain, neck pain, shoulder pain
• Chest pain
• Influenza like illness, malaise, fatigue, chills, asthenia, injection site reaction.

Interactions with Other Medicines

Antibodies in Gamunex 10% may interfere with the response to live viral vaccines such as measles, mumps and rubella. Therefore, use of such vaccines should be deferred until approximately 6 months after Gamunex 10% administration.

Avoid simultaneous administration of Gamunex 10% and Heparin through a single lumen delivery device due to Gamunex 10%, Heparin incompatibilities.