erenumab
Aimovig (erenumab) is a monoclonal antibody from Amgen that blocks the receptor for calcitonin gene-related peptide (CGRP), a key signaling molecule in migraine. Given once monthly by injection, it prevents migraine attacks in adults.
This page is based on FDA prescribing information and the EMA medicine record for erenumab, cross-checked with DailyMed and the National Cancer Institute dictionary; the mechanism is explained in plain language, and analogies are used only where they stay accurate.
How it works
Explains what the medicine does in the body, not dosing, side effects, or safety.
An analogy
During a migraine, the brain's pain system floods the surrounding nerves and blood vessels with a chemical called CGRP, like turning up the volume on a fire alarm. Erenumab plugs the receiver so that alarm signal can't get through, keeping the volume down and preventing attacks from starting.
In simple terms
Erenumab is an antibody that targets the receptor for calcitonin gene-related peptide (CGRP), a small protein released during migraine attacks. CGRP causes blood vessels around the brain to widen and pain signals to intensify. By blocking the receptor that CGRP binds to, erenumab reduces the frequency and severity of migraine attacks. It is given as a monthly injection for prevention — it does not treat an attack that has already begun.
In depth
Erenumab is a fully human IgG2 monoclonal antibody that selectively binds the CGRP receptor (a calcitonin receptor-like receptor, CALCRL, complexed with RAMP1). By occupying the receptor's ligand-binding site, it prevents CGRP from activating downstream Gs-protein signaling and cAMP production in trigeminal ganglion neurons and meningeal vessels. This reduces neurogenic vasodilation, trigeminovascular activation, and peripheral and central sensitization implicated in migraine pathophysiology. Unlike small-molecule gepants, erenumab targets the receptor rather than the ligand and has a long half-life suitable for monthly subcutaneous dosing.
See it in motion
A schematic animation of the mechanism — simplified for clarity, not drawn to scale.
Erenumab plugs the receiver so that alarm signal can't get through
- During a migraine, the brain's pain system floods the surrounding nerves and blood vessels with a chemical called CGRP, like turning up the volume on a fire alarm.
- By occupying the receptor's ligand-binding site, it prevents CGRP from activating downstream Gs-protein signaling and cAMP production in trigeminal ganglion neurons and meningeal vessels.
- This reduces neurogenic vasodilation, trigeminovascular activation, and peripheral and central sensitization implicated in migraine pathophysiology.
- It is given as a monthly injection for prevention — it does not treat an attack that has already begun.
Target: CGRP receptor (CALCRL/RAMP1)
A receptor complex on trigeminal and vascular cells that transmits CGRP signals during migraine attacks; blocking it dampens the pain and inflammation cascade.
Approved uses
Approved uses differ by country and change over time. Always follow your local prescribing information.
Approved uses in United States
FDA- Preventive treatment of migraine in adults
Approved uses in European Union
EMA- Prophylaxis of migraine in adults who have at least 4 migraine days per month when initiating treatment
Official sources
The statements on this page trace back to these records.
- U.S. Food and Drug Administration: erenumab prescribing information
U.S. Food and Drug Administration
- Aimovig (erenumab) — Summary of product characteristics and package leaflet, English version
European Medicines Agency
- DailyMed: Aimovig (erenumab) prescribing information
DailyMed, U.S. National Library of Medicine
- National Cancer Institute: erenumab
National Cancer Institute
This page explains how the medicine works — it isn’t the patient leaflet. For anything that applies to you, read the leaflet that came with your medicine or ask your pharmacist.
MedUnfold provides educational content and is not medical advice. Always follow your local prescribing information and healthcare professional.