Last reviewed 2026-04-23 · How we verify

Rebif New Formulation + prophylactic Ibuprofen

Rebif (interferon beta-1a) activates interferon signaling pathways to modulate immune responses and reduce inflammation in the central nervous system, while prophylactic ibuprofen mitigates injection-site reactions and systemic inflammatory side effects.

Rebif (interferon beta-1a) activates interferon signaling pathways to modulate immune responses and reduce inflammation in the central nervous system, while prophylactic ibuprofen mitigates injection-site reactions and systemic inflammatory side effects. Used for Relapsing-remitting multiple sclerosis (RRMS), Clinically isolated syndrome (CIS) with high risk of developing MS.

At a glance

Mechanism of action

Rebif is a recombinant interferon beta-1a that binds to interferon-beta receptors on immune cells, enhancing antiviral and immunomodulatory responses that suppress pro-inflammatory Th1 and Th17 cell differentiation. The addition of prophylactic ibuprofen, a non-selective COX inhibitor, reduces prostaglandin-mediated inflammation and pain associated with interferon administration, potentially improving tolerability and adherence.

Approved indications

• Relapsing-remitting multiple sclerosis (RRMS)
• Clinically isolated syndrome (CIS) with high risk of developing MS

Common side effects

• Injection-site reactions (erythema, induration, pain)
• Flu-like symptoms (fever, chills, myalgia, fatigue)
• Headache
• Elevated liver enzymes
• Leukopenia
• Depression

Key clinical trials

• Transition to Rebif New Formulation (PHASE3)

Primary sources

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