Rapid resolution of migraine symptoms after initiating the preventive treatment eptinezumab during a migraine attack: results from the randomized RELIEF trial

BACKGROUND: Eptinezumab is an anti-calcitonin gene-related peptide (CGRP) monoclonal antibody approved for the preventive treatment of migraine. In the phase 3 RELIEF study, eptinezumab resulted in shorter time to headache pain freedom and time to absence of most bothersome symptom (MBS; including nausea, photophobia, or phonophobia) compared with placebo when administered during a migraine attack. The objective of this exploratory analysis was to examine the earliest time points that eptinezumab separated from placebo (P < .05) on headache- and migraine-associated symptoms when administered during a migraine attack. METHODS: RELIEF, a multicenter, parallel-group, double-blind trial, occurred from November 7, 2019, through July 8, 2020. Adults considered candidates for preventive treatment were randomized to eptinezumab 100 mg (N = 238) or placebo (N = 242) administered intravenously over 30 min within 1–6 h of migraine onset. Outcome measures included headache pain freedom/relief and absence of MBS, patient’s choice of photophobia, phonophobia, or nausea, at regular intervals from 0.5 to 48 h after infusion start. Censoring was applied at time of acute rescue medication use. RESULTS: At hour 1, more eptinezumab-treated patients achieved headache pain freedom (9.7%), headache pain relief (38.7%), and absence of MBS (33.2%) versus placebo (4.1%, 26.9%, and 22.1%, respectively; P < .05 all), with separation from placebo (P < .05) through hour 48. Eptinezumab separated from placebo (P < .05) at hour 1 in absence-of-photophobia (29.4% vs 17.0%) and absence-of-phonophobia (41.2% vs 27.2%) and through hour 48. Initial separation from placebo (P < .05) in absence-of-nausea occurred at end-of-infusion (0.5 h; 36.7% vs 25.4%, respectively). CONCLUSION: Preventive treatment with eptinezumab initiated during a migraine attack resulted in more patients achieving headache pain freedom/relief and absence of MBS, with separation from placebo (P < .05) as early as 0.5–1 h following the start of infusion. Rapid resolution of headache- and migraine-associated symptoms by a peripherally acting, intravenously administered antibody suggest a peripheral site of pharmacological action for CGRP blockade. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04152083. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12883-022-02714-1.