Episodic Migraine and Erenumab: A Promising Treatment Option

Understanding Episodic Migraines

Episodic migraine is a debilitating headache disorder characterized by severe throbbing pain that can persist for several days. Sufferers may also experience an ‘aura’, which includes debilitating symptoms such as dizziness, ringing in the ears, vision disturbances, and sensitivity to light. Globally, migraines are recognized as a significant cause of disability, impacting approximately 14% of the population at some point in their lives. In Canada, an estimated 8.3% of individuals, or about 2.7 million people, were diagnosed with migraines during the 2010/2011 period.

Impact of Migraines on Quality of Life

Migraines can severely affect an individual’s quality of life, leading to reduced productivity, increased medical expenses, and higher rates of absenteeism. They are classified into two categories: episodic and chronic. Individuals who experience fewer than 15 migraines per month are considered to have episodic migraines, while those with more than 15 per month are classified as having chronic migraines. Chronic migraines are relatively rare, affecting only 5-8% of those with migraines.

Current Treatment Approaches

While over-the-counter medications such as Advil and Tylenol can alleviate symptoms, doctors often recommend preventive treatments for those suffering from debilitating episodic migraines to decrease their frequency. However, existing preventive medications can vary in effectiveness and may carry undesirable side effects, limiting their use.

Research on Erenumab

Study Overview

A recent study published in the New England Journal of Medicine examined the effectiveness and safety of erenumab, a preventive medication for migraines, through a phase 3 clinical trial. A total of 955 patients aged 18 to 65 with a history of migraines, either with or without aura, were recruited. Participants were screened for three months to confirm they experienced a minimum of four episodic migraines per month. They were then divided into three groups: a control group, a low dose (70mg), and a high dose (140mg) of erenumab, administered via injections over six months. The trial was structured as a multicenter, randomized, double-blind study across 121 sites in North America, Europe, and Turkey. Daily migraine experiences were recorded by the patients.

Findings of the Study

The results aligned with previous clinical trials, showing that patients receiving the low and high doses of erenumab had an average reduction of 3.2 and 3.7 migraine days per month, respectively, compared to a reduction of only 1.8 days in the placebo group. Additionally, by the fourth month, 43.3% of patients on the low dose and 50.0% on the high dose reported halving their average number of migraines, in contrast to 26.6% in the placebo group. This indicates that erenumab may have an initial latency phase before its effects become evident.

The study also evaluated the use of migraine-specific medications among participants. Those on the low and high doses of erenumab reduced their medication usage by an average of 1.1 and 1.6 days, respectively, compared to only 0.2 days for the placebo group. Although the low dose group reported more instances of injection site pain compared to the placebo group, the overall incidence of side effects, such as fatigue, nausea, and hypertension, was similar between the erenumab and placebo groups, suggesting that erenumab is relatively safe for patients.

Conclusion and Future Outlook

Though erenumab is currently administered through injections, which may deter some patients, the study found no significant side effects associated with its use, indicating it is as safe as a placebo injection. These findings offer a hopeful perspective on future treatment options for individuals suffering from migraine headaches.

References

(1) Goadsby, P. J. et al. A Controlled Trial of Erenumab for Episodic Migraine. N. Engl. J. Med. 377, 2123–2132 (2017).
(2) Statistics Canada. Prevalence of migraine in the Canadian household population. https://www.statcan.gc.ca/pub/82-003-x/2014006/article/14033-eng.htm