Satsuma Pharma sinks as migraine drug flunks in Phase III

Satsuma Pharmaceuticals’ (Nasdaq: STSA) shares plunged as much as 84% pre-market and closed down 75.9% at $5.62 yesterday, after it disclosed that its lead product, STS101 (dihydroergotamine [DHE] nasal) powder, has failed in the Phase III EMERGE efficacy trial as an acute treatment for migraine.

Although top-line data showed numerical differences in favor of STS101 3.9mg and 5.2mg versus placebo on the pre-specified co-primary endpoints of freedom from pain and freedom from most bothersome symptom (from among photophobia, phonophobia and nausea) at two hours post-administration, these differences did not achieve statistical significance for either dosage strength. Both dosage strengths of STS101 did, however, demonstrate significant effects on both freedom from pain and most bothersome symptom by three hours post-dose and later time points.

Both STS101 dosage strengths were well-tolerated in the EMERGE trial, with low adverse event rates and no serious adverse events reported.