Satsuma heads back to phase 3 after tweaking delivery device

Top-line data from Satsuma Pharmaceuticals' phase 3 are due in the second half of next year. (CC0 Creative Commons)

Satsuma Pharmaceuticals has presented phase 1 data on its second-generation nasal delivery device. The readout positions Satsuma to start a phase 3 clinical trial designed to enable it to bounce back from a pivotal failure last year.

In September, Satsuma reported the failure of its dry-powder formulation of dihydroergotamine (DHE) as an acute treatment for migraine in the phase 3 EMERGE study. The setback happened despite early-phase data suggesting the candidate, STS101, has lower pharmacokinetic variability than an existing nasal spray that administers the same active ingredient.

Satsuma identified variability in the amount of DHE patients were administering as a potential cause of the failure, leading it to study a second-generation nasal spray and trial higher doses. John Kollins, CEO of Satsuma, thinks the changes will improve the efficacy of STS101.

“With the second-generation STS101 device and improved instructions-for-use, we expect subjects in SUMMIT will consistently self-administer the full DHE dose with less variability than in the previous EMERGE phase 3 trial,” Kollins said in a statement.

Kollins said the changes, coupled to “adjustments to the conduct of the trial,” should result in STS101 demonstrating “robust anti-migraine activity” in the new phase 3. Satsuma is looking to the phase 3 study to generate data that “support product approval with differentiated labeling,” Kollins said.

The second-generation nasal spray requires no assembly or priming by patients and is designed to be easier to use than its predecessor. Satsuma said the disposable device is smaller than available DHE nasal sprays and delivers a full dose in seconds. The device is designed to get DHE to the surface of respiratory mucosa and into systemic circulation. 

Having generated data to suggest the changes have increased the proportion of dose administered on first use and reduced variability, Satsuma is now starting the phase 3 SUMMIT study. Top-line data from the trial, which will test a 5.2-mg dose, are due in the second half of next year.