Erenumab Aids Transition From Chronic to Episodic Migraine

A study using real-world data from an Italian region found two-thirds of patients with chronic migraine (CM) treated with erenumab transitioned to episodic migraine (EM) within 6 months. Results were published in The Journal of Headache and Pain.

Erenumab, which was approved by the FDA in 2018, is a calcitonin gene-related peptide (CGRP) inhibitor administered via self-injection once a month. The treatment blocks the CGRP receptor, which is believed to play a crucial role in migraine. Erenumab can be injected as a 70- or 140-mg dose in adults with migraine.

Based on the number of monthly headache days (MHDs), migraine can be classified as either chronic or episodic. In addition to the ongoing pain accompanying CM, “CM carries a high burden of disability as it is often associated with medication overuse,” the researchers wrote.

To better assess the rate and possible predictors of conversion from CM to EM in patients treated with erenumab, the investigators performed subgroup analyses of a real-life study. All patients included in the study were aged 18 though 65 and treated at 1 of 7 headache centers in the Abruzzo region of Italy between January 2019 and February 2020. To receive erenumab treatment, all patients must have had ≥ 4 MHDs and ≥ 2 prior preventive treatment failures per European Headache Federation and American Headache Society guidelines.

The study population consisted of 91 patients with CM. The researchers assessed attack severity by the 0-10 Numerical Rating Scale (NRS) and determined depressive symptoms based on a Beck Depression Inventory score ≥ 20 or use of antidepressant medications not prescribed for migraine. Other demographic data such as age, sex, and migraine characteristics also were collected.

“Erenumab was administered during in-person visits in a monthly subcutaneous dose of 70 mg, with the option of switching to 140 mg monthly in case of a < 30% decrease in MHDs compared with baseline,” the authors wrote. “Patients with several prior preventive treatment failures could start treatment with a 140 mg monthly dose according to the treating physician’s judgement.”

The investigators found that between months 4 and 6, 62 patients (68.1%) converted from CM to EM while the proportion of converters increased from month 1 to month 5. Due to ineffectiveness or adverse events, 11 patients discontinued treatment before month 6.

Analyses of the total patient population showed:

• Median (interquartile range [IQR]) MHDs decreased from 26.5 (IQR, 20-30) to 7.5 (IQR, 5-16; P < .001) compared with baseline
• Median acute medication days decreased from 21 (IQR, 160-30) to 6 (IQR, 3-10; P < .001)
• Median NRS scores decreased from 8 (IQR, 7-9) to 6 (IQR, 4-7; P < .001)
• Thirty-eight (41.8%) patients reached the converter status without needing an erenumab dose increase from 70  to 140 mg monthly, while 24 (26.4%) patients needed a dose increase
• Concurrent migraine preventive treatments were discontinued in 11 (12.1%) patients
• Median NRS decreased from 8 (IQR, 7-9) to 6 (IQR, 4-7; P < .001) in the overall group
• Significant decreases were found both in converters and in nonconverters

In addition, analyses showed that at months 4 to 6, 16.5% of patients achieved a status of low-frequency episodic migraine, while 28.6% achieved a status of medium-frequency episodic migraine.

The researchers did not find any significant predictors of conversion to EM among the patients’ baseline characteristics. In order to maximize treatment outcomes, larger studies ought to be carried out assessing reliable predictors of favorable response to anti-CGRP treatment, the authors wrote.

“The high rate of conversion to EM in our population of difficult-to-treat patients with a long history of CM and multiple prior preventive treatment failures, including botulinum toxin in ≥ 40% of cases, supports the efficacy of erenumab for the preventive treatment of patients with CM,” they concluded.

Reference

Ornello R, Casalena A, Frattale I, et al. Conversion from chronic to episodic migraine in patients treated with erenumab: real-life data from an Italian region. J Headache Pain. Published online August 15, 2020. doi:10.1186/s10194-020-01171-w