Calcitonin gene-related peptide (CGRP) monoclonal antibodies are the first medications developed specifically to prevent migraine.
CGRP is a small protein involved in the cascade of events that lead to a migraine attack. CGRP helps transmit pain signals in the brain, ramp up inflammation and dilate blood vessels. The CGRP monoclonal antibodies block this protein, by either binding to CGRP itself or binding to the receptor sites found in some parts of the nervous system such as the trigeminal nerve, effectively turning off its ability to stimulate the neurological dysfunction that is a migraine attack.
The Food and Drug Administration (FDA) has approved 4 CGRP medications:
- Aimovig (erenumab)
- Emgality (galcanezumab)
- Ajovy (fremanezumab)
- Vyepti (eptinezumab)
Aimovig, Emgality and Ajovy are a once a month self-injection. Ajovy also has the option to use quarterly, with three injections four times a year. Vyepti is a one-hour intravenous infusion every 3 months.
Medsafe has approved Aimovig and it is available as a 70mg and 140mg dose. It’s available on prescription, but it’s not funded. A 70mg injection costs $678 and 140mg costs $1,356.
Your GP can prescribe Aimovig but some GPs aren’t aware of the CGRP monoclonal antibodies and it is only available through Grafton pharmacy in Auckland.
Medsafe has approved Emgality and it is available as a 120mg injection. Two injections (240mg) are given as a first, loading dose, and then one injection every 4 weeks. Each injection costs from $325.
Your GP can prescribe Emgality for you – it doesn't require a neurologist prescription. Your GP may want to find out more information about it if they're not familiar with prescribing it, because it only became available in New Zealand in September 2022.
Emgality should be available through any chemist in New Zealand. The wholesaler is CDC Pharmaceuticals, but even pharmacies that don't usually purchase medicine from CDC can still get Emgality through them. Prices may vary, but Grafton Pharmacy is Auckland is offering it at $325 per dose, plus a courier fee.
Ajovy has been approved by Medsafe but is not available in New Zealand.
Vyepti has yet to be approved by Medsafe.