Objective: Determine characteristics, service utilization, and adherence for people with migraine being prescribed CGRP- inhibitors in an employer-insured population.

Methods: A retrospective observational cohort analysis was conducted on beneficiaries 18-64 using a multi-employer medical and pharmacy claims database provided by Gallagher (benefits consulting organization). The migraine population was identified using ICD codes (“confirmed” migraine) as well as previously-published criteria for those with multiple visits for “headache” and/or pharmacy claims for migraine-specific drugs (“suspected” migraine). Logistic regression assessed likelihood of being prescribed a CGRP-inhibitor based on clinical and demographical characteristics. Adherence (proportion of days covered, PDC) was analyzed for the population prescribed Aimovig, the most commonly prescribed CGRP-inhibitor during the 12-month study period commencing July 2019 (35.9% of all CGRP-inhibitor claims).

Results: Most (82.2%) migraineurs were female. Out of 31,161 migraineurs, 2,328 (7.47%) were prescribed a CGRP-inhibitor, with a higher percentage of females amongst the migraine group (7.90%) being prescribed CGRP-inhibitors in comparison to males (5.49%). The 40-49 age group had the highest proportion of members prescribed CGRP-inhibitors (11.58%). Patients with comorbidities such as anxiety and depression were more likely to be prescribed CGRP-inhibitors in both the confirmed and suspected migraine groups. After correcting for start and end dates, 84.91% of patients were deemed adherent on Aimovig, which was defined as >80% (PDC). The average length on therapy for these patients was slightly over 6 months (188 days), with no statistically significant difference between the confirmed and suspected migraine groups. No significant differences in adherence were noted by age group or gender.

Conclusion: This is one of the first studies examining CGRP-inhibitor utilization in a commercially insured population. Adherence was relatively high. Longer term studies are needed to examine CGRP-inhibitor impact on health and cost outcomes.