Guideline for Migraine Prevention Finds Strongest Evidence for CGRP Inhibitors
/By Pat Anson
New guidelines for medications that help prevent migraine show that the strongest evidence supports the use of three CGRP inhibitors: Emgality, Ajovy and Aimovig. There is also strong evidence for using Botox injections to prevent chronic migraine.
The updated guideline was developed by the American Academy of Neurology and American Headache Society, and published in the journals Neurology and Headache. The update is the first since 2012, and incorporate several new treatments, such as medications that inhibit calcitonin gene-related peptides (CGRPs), a protein that triggers migraine pain.
Migraine affects about 39 million people in the United States and 1.1 billion worldwide. In addition to headache pain, migraine can cause nausea, blurriness, and sensitivity to light or sound. Women are three times more likely to suffer from migraines than men.
Acute migraine medications help treat headache pain and other symptoms as they occur, while preventive medications stop migraines from starting. Oral migraine medications need to be taken every day or every other day, while injectable medications are taken once a month or once every three months.Only one oral medication (Nurtec) both treats and prevents migraine attacks.
“There are a variety of effective preventive medications that work in different ways, including newer classes of medications that have been released in the past several years,” said guideline co-author Tamara Pringsheim, MD, a Professor at the University of Calgary. “For people experiencing frequent migraine attacks or attacks that affect the ability to function normally, this guideline can help clinicians determine which preventive medications may be able to help.”
The guideline update is based on a review of 217 studies that evaluated dozens of medications, and includes recommendations for preventing both chronic and episodic migraine. People with chronic migraine have 15 headache days or more each month, while episodic migraine occurs less often.
The guideline ranks each medication based on the evidence being either strong, moderate or weak. No evidence was found to support the use of over a dozen medications sometimes prescribed off-label for migraine, including Klonopin and Cymbalta.
While the strongest evidence supports the newer CGRP inhibitors, moderate evidence exists for some old-line medications such as beta-blockers and anti-seizure medications. However, many of the older drugs are more likely to have side-effects, such as constipation and weight loss.
Some medications, like antidepressants or medications that lower blood pressure, are primarily intended for other health conditions but have been effective in reducing migraine pain for some patients.
“The research shows many different types of medications may be effective for preventing migraine attacks and reducing symptoms,” said co-author Rebecca Burch, MD, Associate Professor at the University of Vermont Larner College of Medicine. “The guideline includes recommendations for both previously established and newer medications. If one type of medication is not working well, a different type may still be effective. It is important for clinicians and patients to know that there are many options.”
The guideline says preventive treatments should be offered to adults who experience four or more migraine days per month or four or more moderate to severe headache days per month, or if migraine is affecting their ability to work or complete daily tasks.
When working with patients to choose medications, the guideline says clinicians should discuss the strength of the evidence, possible side effects, insurance coverage and out-of-pocket expenses. While CGRP inhibitors are some of the most effective medications, they often cost substantially more than older treatments.
A 2023 study found that some cheaper drugs are just as effective at preventing migraine as CGRP inhibitors. Researchers at the Norwegian Center for Headache Research found that two drugs commonly used to treat depression and high cholesterol – amitriptyline and simvastatin – help reduce the use of medications used to treat acute migraine pain. Both drugs are used off-label for migraine prevention.
