Avonex (interferon beta 1a injection)

What is Avonex (interferon beta-1a), and what is it used for?

  • 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.
  • 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.

Can interferon beta-1a be used to treat the COVID-19 coronavirus?

Interferon beta-1a, currently in use to treat multiple sclerosis, and interferon alfa-2b are both under investigation as potential treatments for people with COVID-19 coronavirus disease, the deadly respiratory pandemic caused by the SARS-nCoV-2 virus.

  • Essentially, when confronted with a virus, each cell shoots an emergency flare of interferon to tell the immune system to marshall its defenses.
  • Interferon Beta 1a, specifically, activates macrophages that engulf antigens and natural killer cells (NK cells), a type of immune T-Cell.
  • Those cells are integral in the innate immune system.
  • The theory is, interferon may be able to make the immune system stronger by turning on dormant parts and directing them toward the defense against SARS-nCoV-2's assault.

The problem is, when interferons ramp up the immune system, COVID-19's flu-like symptoms are likely to become worse before they get better; interferon naturally occurring in the body is responsible for all flu-like symptoms to begin with, whether you have the coronavirus or a common cold

So, if someone is already on a ventilator and symptoms are about to overwhelm them, giving them an interferon-based medicine could be catastrophic. This is why interferon therapies for viral infections are typically a last resort -- the potential for dire side effects.

Studies around the world, including a huge WHO study, are looking at different interferons to treat COVID-19 coronavirus, but no existing COVID-19 drug trials in the U.S. included interferons as of April 7, 2020. 

It is possible there is a hesitance to use interferon in America because it was used in the late 1990s and early 2000s to treat Hepatitis C, and its side effects caused a lot of injury to U.S. patients.

Clinicians were lucky if they saw a 30% cure rate treating Hep C with interferon, but the side effects were severe, including: 

  • Drop in white blood cell levels,
  • liver problems, and
  • psychiatric issues.

People would become suicidal, fall into deep depressions.

Data for COVID-19 section provided by Dominic Chan, a Pharm. D. and infectious disease specialist at Legacy Health System in Oregon.

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)?

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. Interferon beta-1a is under investigation as a potential treatment for the COVID-19 coronavirus disease as of April, 2020. There is yet no solid evidence it provides any benefit against the SARS-nCoV-2 virus that causes the deadly respiratory pandemic, but studies are ongoing.

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