Exploratory Efficacy of INP104 by Migraine Attack Severity and Time of Dosing: Results From the Phase 3 STOP 301 Study

Presented at the AAN Annual Meeting, April 2-7, 2022 

Authors: Brian D. Loftus, Michelle Murphy, Christopher J. Fitzpatrick, Sutapa Ray, Stephen B. Shrewsbury, Sheena K. Aurora

Objective: This post hoc analysis investigated self-reported exploratory efficacy for INP104-treated migraine attacks (MAs) based on severity and time of dosing.

Background: INP104 delivers dihydroergotamine mesylate to the upper nasal space using Precision Olfactory Delivery technology to acutely treat migraine. Previously reported data showed that INP104 was well tolerated and associated with improvements in several exploratory efficacy measures. 

Design/Methods: STOP 301 was a Phase 3, open-label study that evaluated the safety, tolerability, and exploratory efficacy of INP104 over long-term use. Following a screening period (28 days) during which patients took their best usual care, eligible patients self-administered INP104 (1.45 mg) over a 24-week treatment period. eDiaries were completed daily.

Results: This analysis included 354 patients who self-administered ≥1 dose of INP104 over 24 weeks, with 4515 MAs treated with INP104. Of patients with mild, moderate, or severe headache intensity prior to INP104 treatment, 2-hour pain freedom was self-reported for 49%, 40%, and 30% of MAs during Weeks 1-12 and 60%, 31%, and 23% during Weeks 13-24, respectively. Pain relief for the first INP104-treated moderate or severe MA was self-reported as early as 15 minutes by 17.3% of patients and 68.9% at 2 hours. Pain freedom at 2 hours was self-reported by 39.4% and 30.9% of patients who treated their first MA with INP104 between 2 and 4 and greater than 4 hours from onset, respectively. Of patients with mild, moderate, or severe headache intensity prior to INP104 treatment, 2-hour pain freedom for the first INP104-treated MA was self-reported by 25.0%, 50.0%, and 12.5% of patients who treated between 2 and 4 hours and 62.5%, 27.3%, and 15.8% who treated greater than 4 hours after onset, respectively.

Conclusions: INP104 may be a promising acute therapy for patients with all symptom severity levels and can be efficaciously administered without treatment window limitations.