The Food and Drug Administration (FDA) has accepted for review the New Drug Application (NDA) for INP104 (Impel NeuroPharma) for the acute treatment of migraine headaches with or without aura in adults.

INP104 uses proprietary technology to deliver a lower dose (1.45mg) of dihydroergotamine mesylate (DHE) to the upper nasal space. The Company believes this formulation may potentially reduce treatment emergent adverse events. An intranasal formulation of DHE that delivers a higher dose is currently approved by the FDA under the brand name Migranal (4mg/mL). 

Results from the phase 3 STOP-301 study, which supported the NDA submission, showed the trial met its primary end points with no new safety signals. Additionally, exploratory efficacy data in the full safety set (patients who received at least 1 dose; n=354) showed that after the first dose, 66.3% of patients achieved pain relief, 38% of patients had pain freedom, and 52% had freedom from their most bothersome migraine symptom at 2 hours. The study also showed that a majority of migraine attacks did not require rescue medication (85%).

The FDA has set a Prescription Drug User Fee Act (PDUFA) target action date of September 6, 2021 for this application. If approved, INP104 will be marketed under the brand name Trudhesa™.

Commenting on the FDA’s acceptance of the NDA, Adrian Adams, chairman and chief executive officer of Impel NeuroPharma, said: “We are hopeful that patients with migraine who are still in search of an acute treatment that is both non-oral and on-demand will have access to such an option later this year and look forward to working closely with the FDA as it completes its review of our application.”


Impel NeuroPharma announces US Food & Drug Administration acceptance of New Drug Application for INP104 for the acute treatment of migraine. [press release]. Seattle, WA: Impel NeuroPharma; January 20, 2021.