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Migraine Pathophysiology
Migraine is a common and highly debilitating neurological condition.6 It typically presents as a unilateral throbbing/pulsating head pain, which is moderate to severe in intensity and may worsen with physical activity.3-5 Migraine is more than just a bad headache, often involving a range of additional symptoms.3,4
Migraine is a primary headache disorder, and can be classified into two major subtypes according to the International Classification of Headache Disorders 3rd edition (ICHD-3)5:
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Migraine without aura:
“Recurrent headache disorder manifesting in attacks lasting 4-72 hours. Typical characteristics of the headache are unilateral location, pulsating quality, moderate or severe intensity, aggravation by routine physical activity and association with nausea and/or photophobia (sensitivity to light) and phonophobia (sensitivity to sound).”5 -
Migraine with aura:
“Recurrent attacks, lasting minutes, of unilateral fully reversible visual, sensory or other central nervous system symptoms that usually develop gradually and are usually followed by headache and associated migraine symptoms.”5
Migraine can be further categorized as chronic or episodic:
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Episodic migraine: Headaches occur on less than 15 days per month.5
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Chronic migraine: Headache occurs on 15 or more days per month for more than 3 months, and has the features of migraine headache on at least 8 days per month5
For more information about the classifications of migraine visit The International Classification of Headache Disorders - ICHD-3.
Calcitonin gene-related peptide (CGRP) is a neuropeptide involved in migraine pathophysiology1,3
- Migraine involves the activation of the trigeminovascular system3
- CGRP is a 37-amino acid neuropeptide encoded by the calcitonin gene widely distributed in both the CNS and PNS. When CGRP is released in migraine, it is a potent dilator of peripheral and cerebral blood vessels7
- CGRP (calcitonin gene-related peptide) signaling plays a key role in migraine pathophysiology by modulating nociceptive signaling within the trigeminovascular system1,3
- Levels of CGRP, within the trigeminal nerve’s sensory fibres, have been shown to increase during a migraine attack1,3
- The interaction of CGRP with CGRP receptors is believed to contribute to migraine pathophysiology3
Aimovig® is the first and only a-CGRP receptor therapy designed to prevent migraine1,2
Aimovig® (erenumab) is a 100% human monoclonal antibody that binds to the calcitonin gene-related peptide (CGRP) receptor . The CGRP receptor This is located at sites that are relevant to migraine pathophysiology, such as the trigeminal ganglion.1
Aimovig® potently and specifically competes with the binding of CGRP and inhibits its function at the CGRP receptor, and has no significant activity against other calcitonin family of receptors.1,2 Aimovig® has been found to be > 5,000-fold more selective for the CGRP receptor than for other human calcitonin family receptors.2
Watch this short video to learn more about the unique mode of action of Aimovig®
References
- Aimovig SmPC available at www.medicines.ie [accessed July 2021]
- Shi L, et al. J Pharmacol Exp Ther 2016; 356: 223-231.
- Russo AF. Annu Rev Pharmacol Toxicol. 2015;55:533-552.
- What is migraine? Migraine Trust https://migrainetrust.org/understand-migraine/what-is-migraine/#page-sec... [Accessed July 2021]
- International Classification of Headache Disorders 3rd edition (ICHD-3) https://ichd-3.org/1-migraine/ [Accessed July 2021]
- Neurological Conditions – Migraine. Brain Research UK Migraine – Neurological condition (brainresearchuk.org.uk) [Accessed August 2021]
- Amara SG et al. Nature 1982; 298:240–44