Eptinezumab treatment was associated with longer interictal headache/migraine periods which corresponded to greater improvements in patient-reported quality of life measures

Introduction Longer periods between headache episodes (interictal periods) may provide greater time for the nervous system to reset from a previous episode, potentially improving disease status and health-related quality of life. This post hoc analysis evaluated this hypothesis by associating patients’ longest interictal periods with improvements in patient-reported outcomes. Methods PROMISE-2 (NCT02974153) was a double-blind, placebo-controlled study evaluating eptinezumab for preventive treatment of chronic migraine (N = 1072). Daily electronic diary data from Weeks 1–12 and Weeks 1–24 were used to identify interictal periods, defined as days between headache episodes. For each patient, the longest interictal period within these intervals was identified and categorized (1–4, 5–9, 10–14, > 14, and > 21 days). For each category, the following patient-reported outcomes were assessed: 6-item Headache Impact Test (HIT-6), Patient Global Impression of Change (PGIC), and patient-identified most bothersome symptom (PI-MBS). Results Excluding interictal periods with > 10% missing data (resulting in 1010 patients with sufficient data), the mean (SD) of longest interictal periods over Weeks 1–12 was 9.4 (11.0) days. A ≥6-point HIT-6 reduction was observed in 78% (56/72) vs 26% (91/351) of patients with a > 21-day vs 1–4-day longest interictal period, respectively; much or very much improvement per PGIC was reported in 90% (65/72) vs 25% (87/348), respectively, and per PI-MBS was reported in 88% (63/72) vs 26% (92/348), respectively. Similar results were observed for Weeks 1–24. Conclusion Longer interictal periods were associated with more patients indicating positive changes in headache-related life impact, disease status, and symptomology. Trial registration: ClinicalTrials.gov (identifier: NCT02974153; registered: 2016-11-23)