Switching of monoclonal antibodies against the calcitonin gene-related peptide or its receptor in migraine. Results from a Spanish Cohort

Abstract

BackgroundSwitching between calcitonin gene-related peptide (CGRP) and monoclonal antibodies (mAbs) may be a beneficial strategy after discontinuation. The aim of this study was to evaluate switching outcomes of effectiveness/tolerability. MethodsRetrospective multicentric study of migraine patients who switched to another CGRP–mAb due to lack of tolerability or effectiveness (defined as <30% reduction of monthly headache days [MHD]). Assessment was performed before and 3 months after switch. The main outcome was the response rate of MHD. Secondary outcomes included other effectiveness/tolerability measures. Results90patients were included: 75(83.3%) women, 72(80%) chronic, and 18(20%) episodic migraine. Mean age was 45.9±11 years and mean duration of migraine was 29.2±12.4 years. Mean time under first mAb prior to switch was 10.4±4.9 months. Most frequent switches were erenumab-galcanezumab 38 (42.2%) and erenumab–fremanezumab 21 (23.3%). Lack of effectiveness (50/90, 55.6%) or tolerability (40/90, 44.4%) provoked switching. Most common adverse events (AEs) leading to discontinuation were constipation and flu-like syndrome in 16 (40%) patients each. Response rate (RR) of MHD 30%–50% occurred in 10 patients (11.1%), ≥50% in 32 (35.6%) and <30% in 48 (53.3%) patients. Significant reduction was proved after switch in MHD (20 [IQR:15–29] vs 13 [IQR:7–23]; p<.001) and monthly migraine days (15 [IQR:12–20] vs 10 [IQR:7–16]; p<.001). After switching, 38 (42.2%) experienced AEs, but tolerability improved in 50% of patients who discontinued due to lack of tolerability. RR compared between switches to different CGRP-mAb classes showed no differences. ConclusionSwitching may become an individualized strategy in migraine refractory patients who discontinue CGRP–mAbs due to lack of effectiveness/tolerability. In this study, supportive data are provided to the growing evidence of switch and future needs are highlighted.