Anti-CGRP Drugs for Migraine Prevention

New Options for Migraine Sufferers

According to the American Migraine Prevalence and Prevention (AMPP) Study, approximately 40 percent of Americans suffering from migraines would benefit from a migraine preventive drug. Less than one-third of these migraine preventive candidates (about 16 million people) are taking one.

A primary reason for this under-utilization of preventive therapies is that traditional oral therapies, like Topamax (topiramate) or Elavil (amitriptyline), are wrought with side effects and take months before a benefit may be achieved.

With the remarkable arrival and FDA approval of three monoclonal antibodies that target calcitonin gene-related peptide (CGRP)—a molecule that is responsible for transmitting pain signals during a migraine attack—migraineurs finally have another drug option to obtain the relief they deserve. There are three anti-CGRP antibodies approved by the FDA, and they are each injectable (given as a shot).

Types of Anti-CGRP Injections

Taking a closer look into why these revolutionary drugs are steps ahead of traditional migraine preventive drugs will provide you with more knowledge to discuss these medication options with your doctor if you do suffer from migraines.

Made for Migraines

Perhaps the greatest achievement with the arrival of the anti-CGRP drugs is that they are specifically designed to prevent migraines because they block CGRP, a protein that we know plays a vital role in migraine development.

Targeting a migraine-related molecule is a wholly unique approach, considering prior migraine preventive drugs were primarily designed to treat other conditions, like high blood pressure or seizures.

Safe and Well-Tolerated

Research suggests that up to 80 percent of people who start a traditional migraine preventive drug, such as Topamax (topiramate) or Elavil (amitriptyline) will discontinue it within a year. The primary reason that these drugs are discontinued is due to their unpleasant side effects, such as cognitive problems, weight gain, and fatigue, among others.

The upside of the anti-CGRP drugs is that they are extremely well-tolerated and safe. In fact, in a phase three trial of the anti-CGRP drug Aimovig in the New England Journal of Medicine, less than 3 percent of the participants withdrew from the trial because of side effects—this is astonishingly low.

It is important to keep in mind, however, that no drug is without any side effects. Due to the fact that the anti-CGRP drugs are injectables (not pills), they may cause an injection site reaction or inflammation on or near the skin site where the medication is injected.

The most common symptoms of an injection site reaction are mild and include redness, tenderness, and/or itching.

In a small percentage of people, Aimovig may cause constipation, Emgality may cause itching (pruritus), and Ajovy may cause a hypersensitivity reaction.

In the end, as with any new medication, it's essential to discuss all the potential side effects of an anti-CGRP drug with your doctor before taking one. Be sure to also review what you should do in the event such an effect occurs.

Treat Episodic and Chronic Migraines

The anti-CGRP drugs can be prescribed to people with both episodic (less than 15 headache days per month) and chronic (15 or more headache days per month) migraines.

This is remarkable considering traditional migraine preventive drugs, like Topamax or Elavil, are only approved to prevent episodic migraines—and the only medication approved to prevent chronic migraines is Onabotulinumtoxin A (Botox)

Fast-Acting

With the current oral preventive migraine drugs, it takes at least eight weeks before a person can expect to see an improvement in their migraines. (An improvement would be considered a decrease in the number, duration, and/or severity of the attacks.)

Part of the reason for this long timeline is that the drug dose at which migraine improvement can be expected (called the "therapeutic dose") cannot be started right away. Instead, a person has to gradually increase the dose of their migraine preventive drug under the guidance of their doctor. This can be a somewhat slow and tedious process.

With the new anti-CGRP antibodies, people may expect migraine improvement within a month of taking their first injection—in some cases, it may even take less than a month.

Administered Once a Month

A fifth advantage is that these three FDA-approved anti-CGRP drugs are single injections given once a month (Ajovy may also be given as three injections once every three months).

The injections are given subcutaneously (just like an insulin shot) through an auto-injector (Aimovig) or a pre-filled syringe (Ajovy and Emgality). The injections can be administered at home by yourself, or given by someone else such as a partner or caregiver.

While an injection may take a little time to get used to, keep in mind they are only once a month—this is a vast improvement over taking a pill once daily (if not multiple times daily).

A Word From Verywell

In summary, compared to older drugs, the anti-CGRP drugs are better tolerated, easier to take, and work more quickly. They also offer chronic migraineurs an alternative (or potentially additional) option to undergoing Botox. Keep in mind, anti-CGRP drugs are not automatic cures, and they do not work for everyone. There are still some concerns experts are mulling over, including the safety of these drugs for childbearing women.

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