What is Avonex (interferon beta-1a), and how does it work?

  • Interferon beta-1a (Avonex) is a protein produced by recombinant DNA technology using genetically engineered Chinese hamster ovary (CHO) cells into which the human interferon beta genes have been introduced. It is used for treating multiple sclerosis (MS).
  • Interferon beta-1a is designed to be identical to interferon beta that is naturally produced by various cells in the body. Interferon beta has antiviral properties and plays a role in regulating the immune response. The exact mechanism by which interferon beta-1a works in the body to treat MS is not known. Interferon beta-1a does not cure MS. Rather, it helps to decrease the number of flare-ups and slows the occurrence of some of the physical disability that commonly occurs in the disease.

What brand names are available for Avonex (interferon beta-1a)?

  • Avonex is the brand name available for interferon beta-1a in the US.

Is Avonex (interferon beta-1a) available as a generic drug?

  • No

Do I need a prescription for Avonex (interferon beta-1a)?

  • Yes


Multiple Sclerosis (MS) Symptoms and Treatment See Slideshow

What are the uses for Avonex (interferon beta-1a)?

  • Avonex (Interferon beta-1a) is a prescription medicine used to treat relapsing forms of multiple sclerosis (MS) in adults. It reduces the occurrence of MS flares and reduces physical disability caused by MS.

What are the side effects of Avonex (interferon beta-1a)?

Common side effects include:

Other side effects include:

Possible serious side effects include:

What is the dosage for Avonex (interferon beta-1a)?

  • Interferon beta-1a should only be administered by intramuscular injection.
  • The recommended dose is 30 mcg injected intramuscularly once a week.
  • Treatment may be started at 7.5 mcg weekly and increased by 7.5 mcg weekly until the full dose of 30 mcg is reached.

Which drugs or supplements interact with Avonex (interferon beta-1a)?


What kind of disease is multiple sclerosis? See Answer

Is Avonex (interferon beta-1a) safe to use during pregnancy or while breastfeeding?

  • Use of interferon beta-1a has not been adequately evaluated in pregnant women. Due to the lack of conclusive safety data, interferon beta-1a should be used in pregnancy only if the potential benefit justifies the potential risk to the fetus.
  • It is not known if interferon beta-1a is excreted in breast milk. As many drugs enter breast milk and can potentially cause harm to the nursing infant, interferon beta-1a should be used cautiously in nursing mothers

What else should I know about Avonex (interferon beta-1a)?

What preparations of Avonex (interferon beta-1a) are available?
  • Single-dose prefilled syringe: 30 mcg/0.5 mL.
  • Powder for injection (single use vial): 30 mcg.
  • Autoinjector: 30 mcg/0.5 ml
How should I keep Avonex (interferon beta-1a) stored?
  • Preferably interferon beta-1a should be stored refrigerated between 2 C to 8 C (36 F to 46 F).
  • If needed, interferon beta-1a powder can be stored at 25 C (77 F) for up to 30 days if a refrigerator is not available. It must be used within 6 hours if refrigerated at 2 C to 8 C (36 F to 46 F) once the powder is diluted with solution
  • The autoinjector and prefilled syringe may be stored at 25 C (77 F) or lower temperatures for 7 days if a refrigerator is not available. Once the product is removed from the refrigerator, it must not be stored above 25 C (77 F).
When was Avonex (interferon beta-1a) approved by the FDA?
  • Avonex was approved by the FDA in 1996.

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Avonex (interferon beta 1a injection) is an injection medication prescribed to treat relapsing forms of multiple sclerosis (MS) in adults. Common side effects include:

Drug interactions, and pregnancy and breastfeeding safety information should be reviewed prior to using this medication.

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