CGRP migraine treatment
Reviewed by our clinical team
People who experience migraines regularly know just how debilitating they can be, and how much they can impact day-to-day life. Although there are many different types of migraines, each affect people in different ways.
Causing serious sensitivity to light and sound and nausea as well as acute head pain, CGRP (Calcitonin Gene-Related Peptide) migraines are quickly becoming a focus of scientific research due to their severity and unique nature. Although we don’t know exactly how common CGRP-specific migraines are, they likely affect a notable percentage of the 10 million people who experience migraines in the UK every year.
In this article, we'll take a look at what CGRP migraines are, how they work, and the promising treatments currently in development with the hopes of providing relief - as well as how you can access them.
What is CGRP?
CGRP stands for Calcitonin Gene-Related Peptide, which is a type of neurotransmitter released by the brain.
Neurotransmitters are a sort of ‘courier’ chemical, delivering important messages through our nervous system to trigger different responses throughout the body. The CGRP neurotransmitter triggers changes in blood vessels and inflammation in the brain tissue, causing what we now know to be CGRP migraines.
Similar to other types of migraine, the pain, sensitivity, and general discomfort that comes with CGRP migraines are a reaction to physiological (physical) changes in the brain. It’s these physical changes that make migraines feel much worse than headaches.
How does CGRP cause migraines?
When levels of CGRP rise in the brain, they set off a chain reaction that results in the symptoms of migraine attack.
When CGRP is released, it tells your body to enlarge and widen blood vessels in the brain, a process known as ‘vasodilation’. This increases blood flow and leads to inflammation in the surrounding tissue. It’s this rapid dilation and inflammation which triggers the symptoms of migraine. This is a similar reaction to what we see in other types of migraine, but CGRP migraines are thought to be unique.
The levels of CGRP present in the brain significantly influences the severity of the migraine episode, but we don’t yet understand why the brain produces CGRP nor why the body reacts in the way that it does. As with other types of migraine, it could be related to the environment or stress levels.
However, we do know that learning more about and controlling CGRP is a key part of understanding - and preventing - these migraines in those that experience them.
What are CGRP inhibitors?
As part of the ongoing effort to alleviate the impact of CGRP migraines, ground-breaking treatments known as CGRP inhibitors have been developed. These inhibitors offer a targeted approach to tackling CGRP by blocking or reducing the body’s absorption of the CGRP protein, aiming to interrupt the process which leads to the debilitating symptoms of migraine headaches.
CGRP inhibitors are ‘monoclonal antibodies’, known as mAbs, which bind to either the CGRP protein itself or its receptors in the brain, preventing them from activating and absorbing the chemical. This interaction disrupts vasodilation and dampens the inflammatory response thought to be responsible for the throbbing pain and discomfort of migraines, providing relief from the intensity and frequency of migraine episodes.
The advent of CGRP inhibitors and mAbs marks a significant leap forward in migraine treatment, but they are still relatively new, and may not be suitable for everyone.
How to take CGRP migraine treatment
In the UK, the NHS currently prescribes three types of anti-CGRP medicines for migraines:
- Fremanezumab (Ajovy)
- Galcanezumab (Emgality)
- Erenumab (Aimovig)
These are self-administered through subcutaneous injections (under the skin) either monthly or quarterly, under the guidance of a healthcare professional, such as your GP or a nurse. A new form, Eptinezumab (Vyepti), which can be injected intravenously, may also soon be available.
It’s thought that these treatments are effective in about 50 to 60% of cases, but you should keep in mind that no single treatment will work for everyone.
Am I eligible?
You'll only be eligible for these medicines only if you've tried at least three other preventative treatments without success, and taken steps to reduce the frequency and severity of your migraines through lifestyle changes. Prescriptions are generally authorised by headache specialists or consultant neurologists, and you'll need to meet specific criteria concerning the frequency and duration of your migraines to qualify.
If you feel CGRP treatment would be beneficial for your symptoms, then speak to your GP. Keep in mind that not all headache clinics offer this treatment, and the ones that do might have long waiting lists. There are also specific criteria and additional precautions for those who are pregnant or breastfeeding.
Anti CGRP side effects
According to the Migraine Trust, CGRP medicines have proven to be relatively safe and effective in minimising the frequency and severity of migraine attacks, with fewer side effects compared to other preventative treatments. The most common side effects reported are:
- Mild reactions at the injection site (pain and swelling)
- Upper respiratory tract infections
- Constipation
- Itching
- Cramps
- Muscle spasms
As with all new treatments, anti-CGRP treatments need to be closely monitored to ensure their safety and effectiveness. People undergoing CGRP treatment are asked to stay in touch with their prescribing clinic, and to keep a headache diary to record and more easily report side effects and reactions.
If you are currently taking any anti-CGRP medication and have concerns about side effects, you should report these to your specialist immediately.
Where to get CGRP mAbs
If you're considering CGRP monoclonal antibodies (mAbs) as a treatment for your migraines, it's important for you to understand how access to these medications works.
Access to anti-CGRP treatments can vary depending on where you are in the UK, and the availability of anti-CGRP treatments may be limited and subject to regional variations. This is because they need to be prescribed by a specialist clinic, and cannot generally be prescribed by a GP.
You should be aware that waiting lists for these specialists can be quite lengthy, and many patients encounter additional challenges in obtaining referrals or face prolonged waiting times before being seen. Additionally, some healthcare providers might require you to demonstrate that you've attempted a range of other preventive treatments under clinical supervision before considering anti-CGRP treatment for migraines.
For advice specific to you and your area, you should book an appointment with your GP to discuss your options.
Other migraine treatments
Although mAbs may not yet be accessible to everyone, there are several other migraine treatment options available, designed to minimise the regularity and severity of migraines, including those triggered by CGRP.
Vydura (Rimegepant)
Vydura, also known as rimegepant, is an oral medication used for treatment of migraines. It belongs to a class of drugs known as gepants and works in a similar way to mAbs, essentially blocking the CGRP receptor, helping reduce pain and other migraine symptoms. One study found that 59% of people experienced pain relief within two hours with Vydura, and 21% of people were pain free within two hours. Vydura is available in wafer form.
Sumatriptan
Sumatriptan is a well-known migraine relief medication belonging to a class of drugs called triptans, which work by narrowing blood vessels and reducing inflammation. Available in various forms such as tablets, injections, and nasal sprays, sumatriptan is a very flexible solution for those looking for migraine relief.
Rizatriptan
Rizatriptan is another triptan medication used to treat migraines helping alleviate symptoms by narrowing blood vessels and targeting inflammation. Rizatriptan is available in tablet form, making it a convenient option.
Conclusion
Although all types of migraines can be uncomfortable and disruptive to daily life, CGRP migraines can be particularly debilitating. Research is still being carried out into why this is, and anti-CGRP treatments are a promising solution. It’s hoped they will become more accessible and effective as time goes on.
For advice on accessing CGRP migraine treatments, or for more personalised migraine advice, speak to your GP or start your consultation.
References
https://www.england.nhs.uk/2020/01/improved-nhs-migraine-care/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3924554/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7050542/
https://migrainetrust.org/live-with-migraine/healthcare/treatments/calcitonin-gene-related-peptide-monoclonal-antibodies/
https://www.nationalmigrainecentre.org.uk/understanding-migraine/factsheets-and-resources/anti-cgrp-treatment-for-migraine/
