Abstract text (incl. figure legends and references)

Question: Calcitonin gene related peptide monoclonal antibodies (CGRP mAbs) are a promising treatment for episodic and chronic migraine. Though many real-world studies have shown benefit at an average treatment time of 3 or 6 months, little is known about its long term efficacy. The objective of this study is to examine the efficacy of CGRP mAb after 1, 2, and 3 years. This longitudinal study will provide insight on the long-term treatment use of CGRP mAb.

Methods: We extracted Electronic Medical Records (EMR) containing migraine frequency data for Cleveland Clinic patients (n =2025) with 6 consecutive months of positive treatment to a CGRP mAb between June 2018 and December 2021. This cohort's (87.5% female, 47.0 ± 13.5 years old, 1586 with chronic migraine) monthly migraine days (MMD) were examined at 1 (n = 822), 2 (n = 407), or 3 (n = 101) years of CGRP mAb treatment. The responses were differentiated into Non-responders (MMD reduction of 25% or less), Responders (MMD reduction between 26-74%) and Super-responders (MMD reduction of 75% or greater).

Results: After 1 year of treatment, 55.5% were Super-responders, 38.4% Responders, and 6.2% became Non-responders. Following 2 years of CGRP mAb use, 53.6% continued a Super-response, 37.6% responded, and 9.1% stopped responding positively. After 3 years, 59.5% maintained a Super-responder status, 29.7% were Responders, and 10.8% had a negative response.

Conclusions: We have seen great benefits in the short-term treatment of this recent agent, and our results show that CGRP mAbs do maintain efficacy after extended periods of treatment, with only a minority losing benefit over time. This longitudinal study provides some clarity for the preserved long term benefit of the use of CGRP MAB for the treatment of migraine.