Fremanezumab

How it works

It binds calcitonin gene-related peptide (CGRP) ligand, blocking its interaction with the receptor and reducing the trigeminovascular signalling that contributes to migraine.

Prescribing in practice

• Hypersensitivity reactions including rash, pruritus and, rarely, anaphylaxis can occur, so advise patients on recognising and reporting these.
• It is recommended for patients with frequent migraine in whom previous preventive treatments have been unsuccessful, in keeping with NICE guidance.
• Review effectiveness after an adequate treatment period and stop if migraine frequency is not meaningfully reduced.

Monitoring

No routine laboratory monitoring is required, but headache frequency should be tracked and patients observed for hypersensitivity reactions.

Counselling the patient

• This is a preventive injection to reduce migraine frequency, not a treatment for an individual attack.
• Report any rash, swelling or breathing difficulty after injecting.
• Keep a headache diary to help judge whether the treatment is helping.

Evidence & guidelines

NICE recommends fremanezumab for migraine prophylaxis in defined circumstances, supported by randomised trials showing reduced monthly migraine days versus placebo.