REBIF

What it is

REBIF is interferon beta-1a (rch) supplied as an injection in pre-filled syringe or multidose cartridge formulations. The pre-filled syringe presentations contain either 22 micrograms or 44 micrograms per 0.5 mL dose, whilst the multidose cartridge presentations contain 66 micrograms or 132 micrograms per 1.5 mL.

Approved indications

— Patients with a single demyelinating event in the central nervous system with an active inflammatory process, if alternative diagnoses have been excluded, and if they are determined to be at high risk of developing clinically definite multiple sclerosis, with high risk inferred from cerebral MRI with 2 or more lesions suggestive of demyelination.

Key safety warnings

Flu-like symptoms are the most common adverse events associated with REBIF administration, including myalgia, fever, chills and asthenia. These symptoms are most prominent at the initiation of therapy but decrease in frequency with continued treatment. Titrating at the initiation of therapy has demonstrated a significant reduction in the severity and incidence of flu-like symptoms. REBIF should be administered with caution to patients with previous or current depressive disorders, in particular to those with antecedents of suicidal ideation. Depression and suicidal ideation are known to occur in increased frequency in the multiple sclerosis population and in association with interferon use. Rare post-marketing cases of serious hepatic injury including autoimmune hepatitis, hepatitis and hepatic failure have been reported with beta-interferon treatment for multiple sclerosis, including with interferon beta-1a. It is recommended that liver function tests be undertaken prior to initiation of treatment with REBIF and monitored periodically thereafter. Cases of pulmonary arterial hypertension (PAH) have been reported with interferon beta products, including interferon beta-1a. PAH has occurred in patients treated with interferon beta products in the absence of other contributory factors, and may occur several years after starting treatment.

Contraindications

REBIF is contraindicated in patients with a history of hypersensitivity to natural or recombinant interferon beta, or to any excipients in the formulation. REBIF is contraindicated in patients with current severe depression and/or suicidal ideation and in women who are or plan to become pregnant while on therapy.

Regulatory history

REBIF pre-filled syringe presentations (22 microgram and 44 microgram) were first registered on the Australian Register of Therapeutic Goods on 5 December 2008. Multidose cartridge presentations (66 microgram and 132 microgram) were registered on 21 January 2010. Pre-filled syringe autoinjector presentations were registered on 21 October 2010. On 15 May 2013, the TGA approved REBIF for an extension of indications to patients with a single demyelinating event at high risk of developing clinically definite multiple sclerosis, concluding that the benefits of the drug in reducing the progression to multiple sclerosis and disease activity outweigh the known safety profile.