LAS VEGAS, NV — Emilee Connors, PhD, of MAP Pharmaceuticals, Mountain View, CA, and colleagues reported at PAINWeek 2012  that the inhaled, investigational drug MAP0004 provided consistent and similar response rates for episodic migraine attacks even after repeated administration.

MAP0004 is an investigational drug that uses the TEMPO inhaler to deliver dihydroergotamine systemically through the lungs. This bypasses the gastrointestinal tract, making gastric stasis unlikely to affect the absorption of the drug into the bloodstream. Gastric stasis is commonly associated with migraines, and it can significantly change the rate of intestinal absorption of an oral tablet, which results in inconsistent responses to the administered drug. When a triptan is administered as a tablet, the Tmax can vary from 60–240 minutes. Administering MAP004 via inhaler achieves a consistent Tmax between 9–17 minutes for dihydroergotamine, though a consistent Tmax does not necessarily represent a consistent clinical response.

This retrospective study analyzed 153 subjects in an open-label, long-term safety study who had had at least 25 qualifying migraines. When subsequent migraines were compared with the first qualifying migraine, or when comparing the 1st, 5th, 15th, and 25th migraines, the analysis did not find significant differences in pain relief at 2 hours (average 51.0%), in pain-free at 2 hours (average 20.9%), in sustained pain relief from 2–24 hours (average 36.6%), or for sustained pain-free from 2– 24 hours (average 15.0%).

Overall, Dr. Connors concluded, the response rate provided by MAP0004 in treating an episodic migraine attack was similar and consistent, for the 1st, 5th, 15th, or 25th migraine.