Novel Migraine Treatment Shows Mixed Results in Phase 3 Efficacy Trial

Investigational migraine drug produces significant effects on both freedom-from-pain and MBS-free endpoints at 3 hours post administration and at additional efficacy measurement timepoints of 4, 6, 12, 24 and 48 hours.

STS101 (dihydroergotamine [DHE] nasal powder; Satsuma Pharmaceuticals, Inc), an investigational drug candidate for the acute treatment of migraine, showed mixed results in a phase 3 efficacy trial.

Topline data from the STS101 SUMMIT trial showed numerical differences favoring STS101 5.2 mg over placebo on the pre-specified co-primary endpoints of freedom from pain and freedom from the most bothersome symptom out of photophobia, phonophobia, and nausea (MBS-free) at 2 hours post-administration. These differences were not deemed statistically significant (p-value <0.05).

However, the novel drug did produce significant effects on both freedom-from-pain and MBS-free endpoints at 3 hours after dose administration and at additional efficacy measurement timepoints of 4, 6, 12, 24 and 48 hours.

“We are surprised and disappointed that STS101 did not demonstrate statistically significant superiority over placebo at 2-hours post treatment on the SUMMIT study co-primary endpoints,” said John Kollins, Satsuma president and chief executive officer, in a press release. “However, based on our interactions to date with the FDA, we believe the results from the STS101 phase 1 pharmacokinetic and ASCEND phase 3 open-label, long-term safety trials will support the STS101 NDA filing and marketing approval.”

STS101 was found statistically superior to placebo on multiple key secondary endpoints that are clinically relevant and recommended for assessment in the acute-treatment-of-migraine efficacy trials in the FDA’s current industry guidance document and/or the International Headache Society’s guidelines for controlled trials.

These endpoints included proportion of patients with pain relief at 2 hours post-dose (p=0.0017) and at all timepoints thereafter; proportion of patients requiring rescue medication within 24 and 48 hours post-treatment (p<0.0001 and p=0.0001, respectively); and proportion of patients with 24-hour sustained freedom from pain, for example, the number of patients with no headache pain at 2 hours post-dose who remained free from pain at all subsequent timepoints through 24 hours (p=0.0479).

STS101 showed a favorable safety and tolerability profile in SUMMIT, which is consistent with clinical trial findings to date. The only treatment-emergent adverse event (TRAE) reported by more than 5% of patients in the SUMMIT trial self-administering STS101 was nasal discomfort, which was reported by 8.3% of patients. No TRAEs or cardiovascular events were reported.

Satsuma said it does not plan to invest in commercializing STS101 and will pursue alternatives to maximize value for shareholders and minimize cash expenditures.

“A large proportion of people with migraine do not achieve sufficient and sustained relief with current treatments, and we believe that in total, the data from the STS101 clinical program, in which more than 1600 subjects treated more than 8500 migraine attacks with more than 10,000 doses of STS101, demonstrate that STS101 has a differentiated profile and may address the unmet needs of many patients,” Kollins added.

Reference

Satsuma Pharmaceuticals Announces Topline Results from SUMMIT Phase 3 Trial of STS101 for the Acute Treatment of Migraine. Satsuma Pharmaceuticals. News release. November 14, 2022. https://www.globenewswire.com/news-release/2022/11/14/2554800/0/en/Satsuma-Pharmaceuticals-Announces-Topline-Results-from-SUMMIT-Phase-3-Trial-of-STS101-for-the-Acute-Treatment-of-Migraine.html