Effectiveness of switching strategies in CGRP monoclonal antibody therapy for migraine: A retrospective cohort study

• Published in: Headache Vol. 65; no. 4; pp. 619 - 630
• Main Authors: Jaimes, Alex, Gómez, Andrea, Pajares, Olga, Rodríguez‐Vico, Jaime
• Format: Journal Article
• Language: English
• Published: United States Wiley Subscription Services, Inc 01.04.2025; John Wiley and Sons Inc
• Subjects: Adult; Antibodies, Monoclonal - administration & dosage; Antibodies, Monoclonal - pharmacology; Calcitonin; Calcitonin gene-related peptide; Calcitonin Gene-Related Peptide - antagonists & inhibitors; Calcitonin Gene-Related Peptide - immunology; Calcitonin Gene-Related Peptide Receptor Antagonists - administration & dosage; Calcitonin Gene-Related Peptide Receptor Antagonists - pharmacology; Cohort analysis; Cohort Studies; Drug dosages; Drug Substitution; Effectiveness; Female; Headache; Humans; Immunotherapy; Male; Middle Aged; Migraine; Migraine Disorders - drug therapy; Monoclonal antibodies; monoclonal antibody; Outcome Assessment, Health Care; Patients; Receptors; Research Submission; Retrospective Studies; Subgroups; switch; migraine; headache; monoclonal antibody; calcitonin gene–related peptide; switch
• ISSN: 0017-8748; 1526-4610; 1526-4610
• DOI: 10.1111/head.14865

Objective To evaluate the effectiveness of first switching between monoclonal antibodies (mAbs) targeting calcitonin gene–related peptide (CGRP) or its receptor in the treatment of migraine. Background Although mAbs targeting CGRP or its receptor have emerged as a leading treatment for migraine prevention, a proportion of patients do not respond. While switching between these antibodies is a common clinical practice in such cases, the effectiveness remains a subject of study. Methods We conducted a retrospective cohort study at a tertiary headache center, analyzing data from clinical records of patients treated with anti‐CGRP mAbs from January 2020 to March 2024. Baseline was defined as the monthly headache days (MHDs) in the 3 months prior to the start of the second mAb. The primary endpoint was the change in MHDs at month 3 and month 6 following the switch. Additionally, we evaluated response rates in both periods. Subgroup analyses were conducted based on changes in mechanism of action. Finally, we assessed the influence of the number of doses of the first mAb and the inter‐treatment interval. Results Out of 1244 initially identified patients, 185 were included in the month‐3 analysis and 123 in the month‐6 evaluation. The median MHDs decreased from 27.0 (interquartile range [IQR] 16.1, 30.0; range 5.0, 30.7) at baseline to 21.0 (IQR 10.0, 30.0; range 0.0, 30.0; p < 0.001) at month 3, and to 20.0 (IQR 10.0, 30.0; range 0.0, 31.0; p < 0.001) at month 6. Subgroup analyses revealed no significant differences in MHDs between maintaining the same target or changing it (baseline: 28.0 [IQR 16.2, 30.0; range 5.0, 31.0] vs. 27.0 [IQR 6.0, 31.0; range 6.0, 31.0]; month 3: 23.0 [IQR 10.0, 30.0; range 0.0, 31.0] vs. 19.0 [IQR 11.0, 30.0; range 1.0, 31.0], p = 0.144; month 6: 24.0 [IQR 11.0, 30.0; range 0.0, 31.0] vs. 17.0 [IQR 10.0, 30.0; range 3.0, 31.0], p = 0.170). There was no association between a ≥50% reduction in MHDs and the number of previous doses of the first mAb (odds ratio [OR] 1.0; 95% confidence interval [CI] 1.0, 1.1; p = 0.189) or the inter‐treatment interval (OR 1.0; 95% CI 0.9, 1.1; p = 0.914). Conclusion Switching between anti‐CGRP mAbs resulted in a reduction in MHDs, with no significant differences based on the mechanism of action. Factors such as the number of doses of the first mAb and the inter‐treatment interval did not appear to predict a ≥50% reduction in MHDs at month 3. Our findings support the viability of switching as an effective treatment option for patients with migraine who do not respond to initial mAb therapy. Plain Language Summary Although anti‐calcitonin gene–related peptide (CGRP) monoclonal antibodies (mAbs) can be highly effective in treating migraine, some patients do not benefit from these treatments. To understand this better, we looked at the clinical records of patients treated with anti‐CGRP mAbs between January 2020 and March 2024, and we compared change in monthly headache days among patients who switched to another mAb. Our results suggest that switching to a different monoclonal antibody could be an effective option in some cases, but studies with a larger number of participants are needed to determine which types of patients may benefit from this therapeutic approach.