Effect of switching to erenumab in non-responders to a CGRP ligand antibody treatment in migraine: A real-world cohort study.

Background: Therapeutic options for migraine prevention in non-responders to monoclonal antibodies (mAbs) targeting Calcitonin Gene-Related Peptide (CGRP) and its receptor are often limited. Real-world data have shown that non-responders to the CGRP-receptor mAb erenumab may benefit from switching to a CGRP ligand mAb. However, it remains unclear whether, vice versa, erenumab is effective in non-responders to CGRP ligand mAbs. In this study, we aim to assess the efficacy of erenumab in patients who have previously failed a CGRP ligand mAb. Methods: This monocentric retrospective cohort study included patients with episodic or chronic migraine in whom a non-response (< 30% reduction of monthly headache days during month 3 of treatment compared to baseline) to the CGRP ligand mAbs galcanezumab or fremanezumab led to a switch to erenumab, and who had received at least 3 administrations of erenumab. Monthly headache days were retrieved from headache diaries to assess the ≥30% responder rates and the absolute reduction of monthly headache days at 3 and 6 months of treatment with erenumab in this cohort. Results: From May 2019 to July 2022, we identified 20 patients who completed 3 months of treatment with erenumab after non-response to a CGRP ligand mAb. Fourteen patients continued treatment for ≥6 months. The ≥30% responder rate was 35% at 3 months, and 45% at 6 months of treatment with erenumab, respectively. Monthly headache days were reduced from 18.6 ± 5.9 during baseline by 4.1 ± 3.1 days during month 3, and by 7.0 ± 4.8 days during month 6 compared to the month before treatment with erenumab (p < 0.001, respectively). Responders and non-responders to erenumab did not differ with respect to demographic or headache characteristics. Conclusion: Switching to erenumab in non-responders to a CGRP ligand mAb might be beneficial in a subgroup of resistant patients, with increasing responder rates after 6 months of treatment. Larger prospective studies should aim to predict which subgroup of patients benefit from a switch.

Sex Hormones and Calcitonin Gene-Related Peptide in Women With Migraine: A Cross-sectional, Matched Cohort Study.

BACKGROUND AND OBJECTIVES: Sex hormones may modulate calcitonin gene-related peptide (CGRP) release in the trigeminovascular system. We studied CGRP concentrations in plasma and tear fluid in female participants with episodic migraine (EM) and a regular menstrual cycle (RMC), female participants with EM and combined oral contraception (COC), and female participants with EM in the postmenopause. For control, we analyzed 3 corresponding groups of age-matched female participants without EM. METHODS: Participants with an RMC had 2 visits: during menstruation on menstrual cycle day 2 ± 2 and in the periovulatory period on day 13 ± 2. Participants with COC were examined at day 4 ± 2 of the hormone-free interval (HFI) and between days 7 and 14 of hormone intake (HI). Postmenopausal participants were assessed once at a random time point. Plasma and tear fluid samples were collected at each visit for determination of CGRP levels with an ELISA. RESULTS: A total of 180 female participants (n = 30 per group) completed the study. Participants with migraine and an RMC showed statistically significantly higher CGRP concentrations in plasma and tear fluid during menstruation compared with female participants without migraine (plasma: 5.95 pg/mL [IQR 4.37-10.44] vs 4.61 pg/mL [IQR 2.83-6.92], p = 0.020 [Mann-Whitney U test]; tear fluid: 1.20 ng/mL [IQR 0.36-2.52] vs 0.4 ng/mL [IQR 0.14-1.22], p = 0.005 [Mann-Whitney U test]). In contrast, female participants with COC and in the postmenopause had similar CGRP levels in the migraine and the control groups. In migraine participants with an RMC, tear fluid but not plasma CGRP concentrations during menstruation were statistically significantly higher compared with migraine participants under COC (p = 0.015 vs HFI and p = 0.029 vs HI, Mann-Whitney U test). DISCUSSION: Different sex hormone profiles may influence CGRP concentrations in people, with current or past capacity to menstruate, with migraine. Measurement of CGRP in tear fluid was feasible and warrants further investigation.

Change of CGRP Plasma Concentrations in Migraine after Discontinuation of CGRP-(Receptor) Monoclonal Antibodies.

Discontinuation of treatment with monoclonal antibodies (mAb) targeting the Calcitonin Gene-Related Peptide (CGRP) pathway leads to an increase in migraine frequency. We aimed to assess changes in free and total CGRP plasma concentrations after the discontinuation of CGRP(-receptor) mAbs. This prospective analysis included 59 patients with migraine (n = 25 erenumab, n = 25 galcanezumab, n = 9 fremanezumab) who discontinued mAbs after ≥8 months of treatment. Patients were visited at the time of the last mAb injection (V1) and 16 weeks later (V2). For control, 30 migraine patients without preventive drug therapy were included. We measured free CGRP plasma concentrations in the erenumab and fremanezumab group and total CGRP concentrations in the galcanezumab group. Free CGRP plasma concentrations did not change after treatment discontinuation [erenumab: V1 31.2 pg/mL (IQR 25.8−45.6), V2 30.3 pg/mL (IQR 22.9−47.6), p = 0.65; fremanezumab V1 29.4 pg/mL (IQR 16.4−61.9), V2 34.4 (19.2−62.0), p = 0.86]. Controls had similar CGRP values of 32.6 pg/mL (IQR 21.3−44.6). Total CGRP concentrations in the galcanezumab group were 5439.3 pg/mL (2412.7−6338.1) at V1, and decreased to 1853.2 pg/mL (1136.5−3297.0) at V2 (p < 0.001). Cessation of treatment with CGRP(-R) mAbs did not have an impact on the free-circulating CGRP concentrations. Total CGRP decreased significantly after three months of treatment discontinuation.