Article Text
Abstract
Background and Importance Monoclonal antibodies (mAb) against calcitonin gene related peptide (anti-CGRP) and its receptor (anti-CGRP-receptor) are effective in the prophylaxis of migraine. However, studies to determine effectiveness and safety on switching between them in non-responders are scarce.
Aim and Objectives To evaluate the real-world clinical effectiveness and safety of mAb switch in migraine patients.
Material and Methods Retrospective cohort study of adult patients who switched between mAb in a tertiary hospital from December 2019 until September 2022. Sociodemographic and clinical data were recorded. Outcome measures: the reduction of Headache Impact Test (HIT-6) scale punctuation and the reduction of monthly migraine days.
Results We analysed 147 patients treated with anti-CGRP or anti-CGRP-receptor. Among these, 20 patients (13.6%) switched between mAb and had at least one follow-up visit after switching. 16 patients (80%) suffered from chronic migraine (CM) with a baseline median days of migraine a month of 15 [13-24], median Regicor scale of 2% [1-3%] and median HIT-6 of 67 [62.5-72.3]. 19 (95%) were female.
Out of these 20 patients, 15 (75%) started with Erenumab and 5 (25%) with Galcanezumab. First mAb switching was performed after a median of 7.4 months treatment [5.9-11.8] (12 from Erenumab to Galcanezumab; 3 from Erenumab to Fremanezumab; 2 from Galcanezumab to Erenumab and 3 from Galcanezumab to Fremanezumab). 5 patients required a second switch, and one received a third mAb. Reasons for first switching: 12 (60%) non-response, 7 (35%) loss of response and 1 (5%) adverse event. 1 patient (5%) discontinued mAb treating during the study period due to lack of effectiveness.
Median reduction in HIT-6 after first and second switching was-2 [-11.5-0],and -3.5 [-11.8-0], respectively. Median reduction of monthly migraine days after first, and second switching was -4.15 [-7-0] and-4.8 [-6.5 to -0.6], respectively.
Constipation (38.7%) and itchiness (3.2%) were the most frequent adverse events during the study period.
Conclusion and Relevance Our findings in 20 treatment-resistant patients indicated that switching between CGRP mAbs could be beneficial to some non-responders to a initial mAb.
Conflict of Interest No conflict of interest