IMUKIN

What it is

Imukin is interferon gamma-1b recombinant human. Imukin is a biologic response modifier, a single-chain polypeptide containing 140 amino acids. Vials contain 2 x 10⁶ IU (100 micrograms) interferon gamma-1b per 0.5 mL. Production is achieved by fermentation of a genetically engineered Escherichia coli bacterium containing the DNA which encodes the human protein, with purification by conventional column chromatography. Imukin is presented as a solution for injection.

Approved indications

— Adjunct for reduction of the frequency of serious infections in patients with Chronic Granulomatous Disease (CGD).

Dosing overview

The recommended dosage for patients with CGD is 1 x 10⁶ IU (50 micrograms)/m² for patients whose body surface area is greater than 0.5 m², and 3 x 10⁴ IU (1.5 micrograms)/kg/dose for patients whose body surface area is equal to or less than 0.5 m². Injections should be administered subcutaneously three times weekly (for example, Monday, Wednesday, Friday). The optimum sites of injection are the right and left deltoid region and anterior thigh.

Key safety warnings

Imukin should be used with caution in patients with pre-existing cardiac disease, including symptoms of ischaemia, congestive heart failure or arrhythmia, as acute and transient constitutional symptoms such as fever and chills frequently associated with administration may exacerbate pre-existing cardiac conditions. Caution should be exercised when treating patients with known seizure disorders and compromised central nervous system function, as central nervous system reactions including decreased mental status, gait disturbance and dizziness have been observed, particularly at doses greater than 5 x 10⁶ IU (250 micrograms)/m²/day. Most of these abnormalities were mild and reversible within a few days upon dose reduction or discontinuation of therapy. Reversible neutropenia and thrombocytopenia which have been observed during Imukin therapy can be severe and may be dose related, and caution should be exercised when administering Imukin to patients with myelosuppression. The stopper of the glass vial contains natural rubber (a derivative of latex) which may cause allergic reactions.

Contraindications

Imukin is contraindicated in patients who develop or have known acute hypersensitivity to interferon gamma, known hypersensitivity to closely-related interferons or to any component of the product.

PBS listing

Imukin injection 2,000,000 I.U. in 0.5 mL is listed on the PBS with streamlined restriction, with an ex-manufacturer price of A$859.78.

Regulatory history

Imukin interferon gamma-1b recombinant human 2 million IU (100 micrograms)/0.5 mL injection vial was first listed on the ARTG on 8 April 1994.