Abstract
Objectives To determine the treatment response when switching from one class of calcitonin gene related peptide receptor monoclonal antibody (CGRP-receptor mab) to another class of calcitonin gene related peptide monoclonal antibody (CGRP mab) in chronic migraine in the real world setting in Australia.
Methods Patients were prescribed erenumab (CGRP-receptor mab) in the setting of either a product familiarisation program or private pay access in 3 headache centres in Australia in 2018 which was discontinued in 2020. In 2021, galcanezumab and fremanezumab (CGRP mab) were made available on the Pharmaceutical Benefits Scheme. We retrospectively analysed the treatment effectiveness to CGRP mab in this cohort with chronic migraine and compare this to their treatment response to erenumab.
Results We analysed 170 patients with chronic migraine treated with erenumab in our original cohort. Out of the 170, we had 88 patients who switched to either galcanezumab or fremanezumab. The average age was 48 years old (rage 18–73), female n= 79 (90%), baseline monthly migraine days, mean 18.6 (SD 7.6), monthly migraine days at 3 months on erenumab was 9.4 (SD 7.6), monthly migraine days at 3 months on CGRP mab was 8.7 (SD 8.2). Out of the 36 patients who were non-responders to erenumab, 24 patients (67%) had a 50% treatment response rate when switched to a CGRP mab.
Conclusion Our analysis support that the CGRP mab treatment effectiveness is similar to CGRP-receptor mab at 3 months in chronic migraine. Non-responders to erenumab benefited from a treatment switch to a CGRP mab.
