Real-world Data Detail Erenumab’s Efficacy in Chronic Migraineurs

After initiating erenumab, patients with predominately refractory chronic migraine had fewer headache/migraine days per month and outpatient visits, according to study results published in Neurology and Therapy.

Erenumab, a monoclonal antibody that was first approved in 2018, is administered monthly via self-injection of a 70- or 140-mg dose. The treatment blocks the calcitonin gene-related peptide (CGRP) receptor—which is believed to play a crucial role in migraine—and is the first mechanism-based and disease-specific preventive treatment for the condition.

However, findings also revealed patients largely continued to be managed via a polypharmacy approach after treatment initiation.

Because erenumab was approved in 2018, few data are available on its impact in real-world settings. To address this knowledge gap, researchers “aimed to characterize the real-world treatment profiles, clinical outcomes, and healthcare resource utilization of patients prescribed erenumab from select major US headache centers.”

This retrospective chart review included data from patients treated at 5 US headache centers between April 2019 and April 2020. The index date was defined as the date of first prescription fill of erenumab, while the baseline period was considered the 3 months prior to the index date.

All patients included (n = 1034) had diagnosed migraine, were treated with erenumab for at least 3 consecutive months, and were 18 years or older at the index date. The mean patient age was 48 years, 86% were female, and most (79%) were White. Common comorbidities included depression, anxiety, and sleep disorders. Patients used erenumab for a mean of 9.3 months.

Analyses revealed:

• Patients had a mean of 5 preventive treatment failures prior to erenumab initiation
• Patients used a mean of 2 preventive treatments (excluding erenumab) and 2 acute treatments during the baseline and study periods
• Among the 793 (77%) patients who initiated erenumab at 70 mg, 572 (72%) patients later escalated to 140 mg
• Among patients with effectiveness data, 45% had improvement in physician-reported migraine severity and 35% experienced at least 50% reduction in mean headache/migraine days per month
• Mean headache/migraine days per month decreased by a mean of 5.6 days, from 18.3 days at baseline to 12.7 days during the study period
• Average number of monthly outpatient visits was 0.43 and 0.30 before and after erenumab initiation, respectively

At the end of the study period, 790 (76%) patients continued with erenumab while 244 stopped treatment. The main reasons for discontinuation included lack of effectiveness, adverse events, and insurance reimbursement.

In addition, “At baseline, 50% of patients had migraine classified as ‘severe’ and 37% had migraine classified as ‘moderate’ on the basis of physician assessment of severity,” the authors wrote. “After erenumab initiation, only 19% had migraine classified as ‘severe’ and 49% had migraine classified as ‘moderate.’ Among the 877 (85%) patients with this information available in both baseline and study periods, 397 (45%) improved in severity after erenumab initiation.”

Twenty-three patients reported constipation prior to erenumab initiation while 216 reported the adverse event throughout the study period. However, 22% of these patients “were prescribed treatments during the study period other than erenumab that may be potentially associated with constipation,” the authors said.

Because tapering and discontinuation of other treatments would typically occur after migraineurs achieved a stable response to erenumab, the current study period may not have fully captured complete treatment discontinuation patterns or dose modifications in the average 9-month follow-up.

Over half of patients in the study also suffered from behavioral nervous system disorders, which are risk factors for chronic migraine.

“Further research is needed to gain a better understanding of migraine treatment patterns and to establish a clear approach to modifying existing migraine treatment profiles after anti-CGRP pathway therapies are initiated,” the researchers wrote.

Better tools to measure and assess constipation in a clinically meaningful way are also warranted.

The potential for missing or inaccurate data reported in medical charts mark a limitation to the study, in addition to a lack of standardization in physician reporting of data across centers. Results may not be generalizable to all those with migraine and those with episodic migraine.

“Further long-term research across various clinical practice settings is needed to better understand real-world patient outcomes and treatment patterns with erenumab therapy,” the authors concluded.

Reference

Faust E, Pivneva I, Yang K, et al. Real-world treatment profiles, clinical outcomes, and healthcare resource utilization of patients with migraine prescribed erenumab: a multicenter chart-review study of US headache centers. Neurol Ther. Published online April 15, 2021. doi:10.1007/s40120-021-00245-4