Safety and Efficacy of Concomitant Erenumab and INP104 Use From the Phase 3 STOP 301 Study in Migraine Patients

Presented at the AAN Annual Meeting, April 22-27, 2023 

Authors: Zubair Ahmed, Robert Vann, Christopher Fitzpatrick, Sutapa Ray, Stephen Shrewsbury, Sheena Aurora

Objective: To report safety and efficacy in migraine patients who concomitantly used erenumab and INP104 over 24 weeks.

Background: Breakthrough migraine attacks can occur while a patient is on preventive therapy; therefore, effective acute medications that can be used concomitantly without an increased risk of adverse events (AEs) are needed. INP104 is a combination of dihydroergotamine mesylate (DHE) and Precision Olfactory Delivery approved for the acute treatment of migraine.

Design/Methods: This was a post hoc analysis of the Phase 3, open-label study (STOP 301) that assessed the safety, tolerability, and exploratory efficacy of INP104 in migraine. Patients used their best usual care during a 28-day screening period. Eligible patients were provided INP104 to nasally self-administer (1.45 mg) with self-recognized attacks over 24 weeks. Concomitant preventive migraine medications were permitted if stable and not contraindicated with DHE. Erenumab was the only approved calcitonin gene-related peptide monoclonal antibody at study initiation.

Results: Over 24 weeks, 8 patients concomitantly used erenumab and INP104; 5 reported no AEs. Most AEs were mild or moderate in severity. One patient reported severe AEs, which included bronchitis and serious AEs of pulmonary embolism and visual disturbance; none was treatment related. One mild case of abnormal olfactory test in another patient was possibly treatment related. At baseline, 2-hour pain and most bothersome symptom (MBS) freedom was self-reported by 22.0% and 51.5% of patients on their best usual care, respectively. At months 1, 2, 3, 4, 5, and 6, 32.3% and 54.3%, 37.1% and 70.8%, 33.3% and 50.0%, 40.3% and 68.1%, 28.0% and 42.7%, and 26.7% and 33.3% self-reported 2-hour pain and MBS freedom post-INP104, respectively.

Conclusions: Results suggest that INP104 may be an effective and well-tolerated acute therapy for migraine patients who concomitantly use erenumab as a preventive therapy, with sustained benefits over 6 months.