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Interferon beta-1a (Avonex)

Biogen · FDA-approved active Small molecule ✓ Verified May 2026

Interferon beta-1a (Avonex) is a Interferon beta Small molecule drug developed by Biogen. It is currently FDA-approved for Relapsing-remitting multiple sclerosis, Secondary progressive multiple sclerosis with active disease. Also known as: Avonex.

Interferon beta-1a activates interferon signaling pathways to modulate immune responses and reduce inflammatory activity in the central nervous system.

Interferon beta-1a (Avonex) is used to treat Multiple Sclerosis, specifically Relapsing-Remitting Multiple Sclerosis. It is considered a first-line disease-modifying treatment (DMT) for this condition.

At a glance

Generic nameInterferon beta-1a (Avonex)
Also known asAvonex
SponsorBiogen
Drug classInterferon beta
TargetInterferon-beta receptor (IFNAR)
ModalitySmall molecule
Therapeutic areaImmunology
PhaseFDA-approved

Mechanism of action

Interferon beta-1a binds to interferon-beta receptors on immune cells and other tissues, triggering JAK-STAT signaling and other downstream pathways that enhance antiviral and immunoregulatory responses. In multiple sclerosis, this leads to reduced T-cell proliferation, decreased pro-inflammatory cytokine production, and reduced migration of immune cells across the blood-brain barrier, thereby slowing disease progression and reducing relapse rates.

Approved indications

Common side effects

Key clinical trials

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

Competitive intelligence

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Frequently asked questions about Interferon beta-1a (Avonex)

What is Interferon beta-1a (Avonex)?

Interferon beta-1a (Avonex) is a Interferon beta drug developed by Biogen, indicated for Relapsing-remitting multiple sclerosis, Secondary progressive multiple sclerosis with active disease.

How does Interferon beta-1a (Avonex) work?

Interferon beta-1a activates interferon signaling pathways to modulate immune responses and reduce inflammatory activity in the central nervous system.

What is Interferon beta-1a (Avonex) used for?

Interferon beta-1a (Avonex) is indicated for Relapsing-remitting multiple sclerosis, Secondary progressive multiple sclerosis with active disease.

Who makes Interferon beta-1a (Avonex)?

Interferon beta-1a (Avonex) is developed and marketed by Biogen (see full Biogen pipeline at /company/biogen).

Is Interferon beta-1a (Avonex) also known as anything else?

Interferon beta-1a (Avonex) is also known as Avonex.

What drug class is Interferon beta-1a (Avonex) in?

Interferon beta-1a (Avonex) belongs to the Interferon beta class. See all Interferon beta drugs at /class/interferon-beta.

What development phase is Interferon beta-1a (Avonex) in?

Interferon beta-1a (Avonex) is FDA-approved (marketed).

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

Common side effects of Interferon beta-1a (Avonex) include Flu-like symptoms (fever, chills, myalgia), Injection site reactions, Headache, Elevated liver enzymes, Leukopenia, Depression.

What does Interferon beta-1a (Avonex) target?

Interferon beta-1a (Avonex) targets Interferon-beta receptor (IFNAR) and is a Interferon beta.

Related

Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing