CGRP Preventives

What is CGRP (calcitonin gene related protein)?

CGRP is a neuropeptide.  Many people are familiar with the term neurotransmitter.  A neurotransmitter is released from one neuron and binds to a receptor on a 2nd neuron.  Neuropeptides do this but their receptors are also found on non-neurons.  In the case of CGRP receptors in the brain, they are found on microglia and on blood vessels.  There are CGRP receptors all over the body.  Because CGRP is so widespread in the human body, it is surprising to Dr. Loftus that there are not more side effects from these medications that are so useful to treat migraine.
CGRP has been demonstrated to be elevated during migraine headaches (and cluster headaches).  Once the headache resolves, the level drops.  IV infusion of CGRP can trigger headaches in migraine patients.  For this reason, CGRP has been targeted for both acute migraine treatment and migraine prevention.
Monoclonal antibodies are antibodies that have been designed for a specific target.  The part of the antibody that determines the target is referred to as the warhead.  Monoclonal antibodies are now used in dozen of diseases.  They are not metabolized by the liver or kidney.  Other than local skin reactions if they are injected and the possibility of the development of an allergy, the monoclonal antibodies are essentially side effect free outside of their effects on the target.  In the case of migraine, monoclonal antibodies can target either CGRP itself (attacking the key) or target CGRP receptor (attacking the lock).

Aimovig®

Aimovig is a monoclonal antibody that targets the CGRP receptor.  It was the first CGRP related migraine agent approved by the FDA (May 2018).  There are two doses, 70 mg and 140 mg on the market.  The drug is given monthly.  The primary side effect of targeting the CGRP receptor appears to be slowing of the GI tract.  Slowing the GI track can cause constipation is it raises the pressure inside the gut.  For this reason, Dr. Loftus avoids this medication in patients with known gut issues such as ulcer and Chrohn’s disease.  More controversial is if Aimovig causes hypertension in some patients.  The FDA added a warning that it does based upon post marketing reports but the controlled data did not show an increase in blood pressure compared to the placebo arm of the study.

Ajovy®

Ajovy is a monoclonal antibody that targets the CGRP neuropeptide itself.  If was the first of three monoclonal antibodies targeting CGRP approved by the FDA (September 2018) and the first time the drug was presented to physicians post approval was at the Southern Headache Society conference in 2018.  It was not found to cause constipation.  The drug was proven to work in chronic migraine given 3 shots every 3 months.  In episodic migraine the dose proven to work was one shot per month or three shots given every 3 months.  For chronic migraine, 1 shot each month was never tested for prevention.  Despite this, 1 shot per month is the most common dosing schedule used for Ajovy for chronic migraine.

Emgality®

Emgality is a monoclonal antibody that targets the CGRP neuropeptide and was the 2nd drug of this type that was FDA approved to prevent migraine headaches.  The dosing of this medication for migraine is 2 – 120 mg shots to start treatment and then 1 shot each month.  The same dose is used for both chronic migraine and episodic migraine.

Vyepti®

Vyepti is a monoclonal antibody that targets the CGRP neuropeptide and was the 3rd drug of this type approved by the FDA.  It is given intravenously to patients every 3 months.  Two doses are approved, both 100 mg every 3 months and 300 mg every 3 months.  Because it is intravenous, it is not associated with any local shot reaction.

Nurtec®

Nurtec is an oral CGRP receptor blocker that was FDA approved to treat acute migraine when it was approved for use as a migraine preventative.  It therefore because the only drug ever approved for both acute migraine treatment and migraine prevention.  For prevention, it is given every other day.  Like Aimovig®, it is associated with constipation but the constipation rate is lower than Aimovig® presumably because it is given every other day.  This drug works best for constipation when patients have another acute medication to take for headaches that occur on days that Nurtec is not scheduled to be taken.

Qulipta®

Qulipta is an oral CGRP receptor blocker that has been demonstrated to prevent migraine in both episodic migraine and chronic migraine. It comes in 3 doses, 10 mg, 30 mg, and 60 mg.  The lowest dose is really designed so one can use it if the patient is on a drug that slows the metabolism of the medication.  30 mg and 60 mg are the more commonly used doses for migraine prevention.  Constipation is the primary negative side effect.

 

 

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five star patient reviews dr loftus
Five star patient reviews

Jessica E.(Patient Since 2022)

Dr. Loftus is awesome. This was my first time coming to see him–from out of town. My previous neurologist had literally given up on helping my status migraine. She didn’t even know that’s what it was (or if she did, never mentioned it). I was desperate and needed someone who could help and he came recommended by a friend. The 2.5 hour drive was well worth it. He listened to me for quite a long while, asked questions, and had A PLAN. Exactly what I needed. If a didn’t work, there would be b, then option c. He asked questions about things that I had never thought about (and neither had many other doctors). I left with optimism I haven’t had for a long time. Listening was like drinking through a firehose. There was a lot of information to take in, and when you don’t feel well to start, it can be a lot. I tried to take high level notes but luckily at the end of the visit, the office gave me a summary of what we had discussed and detailed instructions of his plan for treatment and how to take medications. I’m looking forward to being able to consult with him virtually at future appointments and know that he has treatments available (in Houston) if I need them. By the way, get the iHeadache app. It is so handy. I’d been looking for one for so long and it’s fantastic; finally got rid of the old notebook tracker.

Christof M.(Patient Since 2019)

Happy my son is progressing toward less frequent headaches! It has been many years and many different doctor visits until we have reached this point and it is great to see glimpses of our son come back again. Thank you!

Dr. Brian Loftus, MD square profile picture

Providing headache and hyperhidrosis care & wellness for over 25 years.

Dr. Brian Loftus, M.D.

Dr. Loftus is Board Certified in Headache Medicine as well as Neurology. In private practice since 1994, Dr. Loftus’ practice has gotten busier and he has decided to concentrate his practice in areas that he can make a particular difference compared to other neurologist. Therefore, Dr. Loftus has chosen to focus his neurology practice on headaches & head painheadaches during pregnancy, and hyperhidrosis. In the spring of 2006, Dr. Loftus relocated his practice from the Texas Medical Center to Bellaire, just 5 miles west. He has been named a Texas Monthly “Super Doctor” and an H Texas magazine “Top Doctor” multiple times.