Galcanezumab

How it works

It binds to calcitonin gene-related peptide (CGRP) ligand, preventing it from activating its receptor and reducing the neurovascular signalling involved in migraine and cluster headache.

Prescribing in practice

• Hypersensitivity reactions including rash, pruritus and, rarely, anaphylaxis can occur, sometimes days after administration, so counsel patients to report these.
• For migraine prophylaxis it is recommended where previous preventive treatments have failed, in line with NICE guidance.
• Review effectiveness after an adequate treatment period and stop if there is no worthwhile reduction in attack frequency.

Monitoring

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

Counselling the patient

• This is a preventive injection to reduce attack frequency, not a treatment for an acute attack.
• Report any rash, swelling or breathing difficulty, which can occur even some days after the injection.
• You can be taught to give the injection yourself with the prefilled device.

Evidence & guidelines

NICE recommends galcanezumab for migraine prophylaxis in defined circumstances, and randomised trials support its efficacy in migraine and episodic cluster headache.