Improving to Four or Fewer Monthly Headache Days Per Month Provides a Clinically Meaningful Therapeutic Target for Patients with Chronic Migraine

INTRODUCTION: Treatment target goals for patients receiving preventive migraine treatment are complicated to assess and not achieved by most patients. A headache “number” could establish an understandable treatment target goal for patients with chronic migraine (CM). This study investigates the clinical impact of reduced headache frequency to ≤ 4 monthly headache days (MHDs) as a treatment-related migraine prevention target goal. METHODS: All treatment arms were pooled for analysis from the PROMISE-2 trial evaluating eptinezumab for the preventive treatment of CM. Patients (N = 1072) received eptinezumab 100 mg, 300 mg, or placebo. Data for the 6-item Headache Impact Test (HIT-6), Patient Global Impression of Change (PGIC), and acute medication use days were combined for all post-baseline assessments and analyzed by MHD frequency (≤ 4, 5–9, 10–15, > 15) in the 4 weeks preceding assessment. RESULTS: Based on pooled data, the percentage of patient-months with ≤ 4 MHDs associated with “very much improved” PGIC was 40.9% (515/1258) versus 22.9% (324/1415), 10.4% (158/1517), and 3.2% (62/1936) of patient-months with 5–9, 10–15, and > 15 MHDs, respectively. Rates of patient-months with ≥ 10 days of acute medication use were 1.9% (21/1111, ≤ 4 MHDs), 4.9% (63/1267, 5–9 MHDs), 49.5% (670/1351, 10–15 MHDs), and 74.1% (1232/1662, > 15 MHDs). Of patient-months with ≤ 4 MHDs, 37.1% (308/830) were associated with “little to none” HIT-6 impairment versus 19.9% (187/940), 10.1% (101/999), and 3.7% (49/1311) of patient-months with 5–9, 10–15, and > 15 MHDs, respectively. CONCLUSION: Participants improving to ≤ 4 MHDs reported less acute medication use and improved patient-reported outcomes, suggesting that 4 MHDs may be a useful patient-centric treatment target when treating CM. TRIAL REGISTRATION: ClinicalTrials.gov (Identifier: NCT02974153) (https://clinicaltrials.gov/ct2/show/NCT02974153). SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40122-023-00525-x.