Avonex® (Interferon Beta-1a)

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Avonex® is interferon beta-1a. Interferons are proteins produced naturally in the human body to help fight infections and regulate the immune system. Beta interferons have been shown to slow down activity and disease progression in MS. They do this by helping regulate the immune system, reducing attacks on myelin or nerves. Researchers are still investigating exactly how this process works. Clinical trials found that Avonex® (interferon beta-1a) has a significant beneficial effect in people with relapsing-remitting multiple sclerosis (RRMS) by reducing the accumulation of permanent physical disability, relapse frequency and disease activity measured by active lesions on brain magnetic resonance images (MRI).

A 30-microgram dose of Avonex® is taken weekly by injection into muscle, usually in the thigh or upper arm. You will receive a month’s supply in a box, which will consist of four injections. Your doctor or MS nurse may provide you with a special titration kit starting with a smaller dose and gradually increasing the dose during the first three weeks of treatment to help manage any side effects. Many people with MS learn to give themselves the injection or have it given by a partner or family member, following initial supervision and training by a qualified healthcare professional.

Avonex® helps most people with MS, but it may have side effects in some people. All medications have side effects. It is important to notify your health professional if you experience any side effects or are feeling unwell.

The most common side effect is to feel ‘flu-like’ symptoms, e.g. headache, tiredness, muscle aches, joint pain, shivering and fever. These side effects generally occur less often as therapy continues. Other common side effects are fatigue, nausea, vomiting or diarrhoea, pain or migraine, muscle stiffness or spasms, dizziness, sleeplessness, soreness, redness or bruising at the injection site, loss of appetite, runny nose, increased sweating or flushing, menstrual upsets, rash, hair loss, and reduced sensitivity to touch however, you may not experience any of them. Serious side effects are rare.

Other side effects may also occur in some patients – tell your doctor if you notice anything else that is making you feel unwell.

Avonex® is suspected to have caused or may be expected to cause, an incidence of human fetal malformations or irreversible damage. These drugs may also have adverse pharmacological effects.

If you are currently pregnant or trying to become pregnant, please discuss your individual circumstances and treatment options with your neurologist or healthcare team.

The levels of interferon beta-1a in breastmilk are minuscule. In addition, because interferon is poorly absorbed orally, it is not likely to reach the bloodstream of the infant.

If you are currently breastfeeding, please discuss your individual circumstances and treatment options with your neurologist or healthcare team.

Avonex® has been approved by the Therapeutic Goods Administration (TGA) and is available through the Pharmaceutical Benefits Scheme (PBS). Please discuss with your neurologist whether Avonex® is the right treatment for you. Your neurologist will need to obtain an authority to prescribe the medication for you. There are a number of criteria you must meet before your doctor receives authority to write this prescription.

For details of the criteria you need to meet to receive Avonex® through the PBS, please visit the official PBS website at:

You will need to click on the red Authority Required (STREAMLINED) link.

If you are eligible for medications through the PBS, you will need to pay a contribution fee each time your prescription is dispensed. The Federal Government pays for the remaining cost. The amount of the contribution fee depends upon whether or not you have a pension or concession card. The amount of this fee is set each year by the Federal Government.

Further information about the PBS, your entitlements and details regarding the PBS safety net (which protects patients and their families requiring a large number of PBS items) is available through the Medicare Australia website at:

If you are not eligible for Avonex® through the PBS, for example if you are a visitor from overseas, your neurologist may write a private prescription. In this instance you will have to pay the full cost to the pharmacy that dispenses your medication. You will need to request a quote from your pharmacist for the price of any medication which is not subsidised by the PBS.

Avonex® (Interferon Beta-1a)

Forms of MS used for:
Relapsing forms of MS, Clinically Isolated Syndrome at risk of MS (specific criteria)
Administration route:
Intramuscular injection (injection into muscle)
Dosage and frequency:
Once per week
Refrigerate 2-8°C
TGA approval date:
August 2001
Available on PBS:

General Information and Assistance

Not all pharmacies keep Avonex® in stock. It is therefore important to let your pharmacist know a few days before you need the medication so that they can order it in for you.

Avonex® Bioset vials need to be stored below 25°C. Avonex® prefilled syringes need to be kept between 2-8°C. If the outside temperature is warm it is a good idea to take your medication home in an ice cooler. Your pharmacist may be able to assist with this.

Biogen Idec runs a Patient Support Program called MS Alliance. The website for MS Alliance is and the toll-free helpline is 1800 286 639.

For more information

Speak to your neurologist about what treatment best suits your individual circumstances.

MS Nurses can also provide information, training and ongoing support in managing your immunotherapy.

MS Australia does not recommend any specific disease-modifying treatment for people living with MS. Decisions about any treatments, taking into consideration the potential benefits and side effects for each individual’s circumstances, should be made in careful consultation with the person’s neurologist.

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Avonex®(Interferon beta-1a)