, according to results from a phase 3 clinical trial. In development by Impel NeuroPharma, the new formulation could offer patients an at-home alternative to intramuscular infusions or intravenous injections currently used to deliver DHE.
“Our analysis of the data suggests that nothing new or untoward seemed to be happening as a result of delivering DHE to the upper nasal space,” Stephen Shrewsbury, MD, chief medical officer of Impel NeuroPharma, said in an interview. The company released key results from its phase 3 clinical trial, while a poster examining patient satisfaction was presented by Dr. Shrewsbury at the virtual annual meeting of the American Headache Society.
An improved intranasal formulation
The product isn’t the first effort to develop an inhaled form of DHE. An inhaled version called Migranal, marketed by Bausch Health, delivers DHE to the front part of the nose, where it may be lost to the upper lip or down the throat, according to Dr. Shrewsbury. Impel’s formulation (INP104) delivers the drug to the upper nasal space, where an earlier phase 1 trial demonstrated it could achieve higher serum concentrations compared with Migranal.
In 2018, MAP Pharmaceuticals came close to a product, but it was ultimately rejected by the Food and Drug Administration because DHE was not stable in the propellant used in the formulation. This time is different, said Dr. Shrewsbury, who was chief medical officer at MAP before joining Impel. The new device holds DHE and the propellant in separate compartments until they are combined right before use, which should circumvent stability problems.
Dr. Shrewsbury believes that patients will welcome an inhaled version of DHE. “People with migraines don’t want to have to go into hospital or even an infusion center if they can help it,” he said.
The study was one of a number of presentations at the AHS meeting that focused on novel delivery methods for established drugs. “The idea of taking things that we know work and improving upon them, both in terms of formulation and then delivery, that’s a common theme. My impression is that this will be an interesting arrow to have in our sling,” said Andrew Charles, MD, professor of neurology and director of the UCLA Goldberg Migraine Program, who was not involved in the study.
Open-label trial results
The STOP 301 phase 3 open-label safety and tolerability trial treated over 5,650 migraine attacks in 354 patients who self-administered INP104 for up to 52 weeks. They were provided up to three doses per week (1.45 mg in a dose of two puffs, one per nostril). Maximum doses included two per day and three per week.
There were no new safety signals or concern trends in nasal safety findings. 15.0% of patients experienced nasal congestion, 6.8% nausea, 5.1% nasal discomfort, and 5.1% unpleasant taste.
A total of 66.3% of participants reported pain relief by 2 hours (severe or moderate pain reduced to mild or none, or mild pain reduced to none) following a dose, and 38% had freedom from pain. 16.3% reported pain relief onset at 15 minutes, with continued improvement over time. During weeks 21-24 of the study, 98.4% and 95% of patients reporting no recurrence of their migraine or use of rescue medications during the 24- and 48-hour periods after using INP104. “Once they got rid of the pain, it didn’t come back, and that’s been one of the shortcomings of many of the available oral therapies – although some of them can be quite effective, that effect can wear off and people can find their migraine comes back within a 24- or 48-hour period,” said Dr. Shrewsbury.
The drug was also rated as convenient, with 83.6% of participants strongly agreeing (50%) or agreeing (33.6%) that it is easy to use.
“It certainly looks like compliance will be good. The possibility is that this will be quite useful,” said Dr. Charles, who is also enthusiastic about some of the other drug formulations announced at the meeting. “It really is just fun times for us as clinicians to be able to have so many different options for patients,” he said.
Dr. Shrewsbury is an employee of Impel NeuroPharma, which funded the study.* Dr. Charles consults for Amgen, BioHaven, Eli Lilly, Novartis, and Lundbeck.
SOURCE: Shrewsbury S, et al. AHS 2020. Abstract 832509.
*Correction, 6/19/20: An earlier version of this article misstated the name of Impel NeuroPharma.