Vistagen reports preliminary open-label data from PALISADE-4 extension for fasedienol

Vistagen announced on September 22, 2026 preliminary data from the open-label extension portion of its Phase 3 "PALISADE-4" study evaluating fasedienol nasal spray for the acute treatment of social anxiety disorder, according to an 8-K filed the same day.

In a recent analysis of subjects who elected to participate in the extension (safety population of 322), fasedienol dosed at 3.2 µg and taken as needed up to six times per day for up to 12 months was well tolerated, with no new drug-related safety findings.¹ The discontinuation rate due to adverse events was 1.6 percent (5 of 322 patients), with none attributed to fasedienol, and more than 95 percent of treatment-emergent adverse events were mild or moderate in severity.¹ Adverse events occurring in more than 5 percent of subjects included headache (18.0 percent), upper respiratory tract infection (9.9 percent), rhinorrhoea (7.1 percent), and oropharyngeal pain (5.3 percent).¹ There were no serious adverse events tied to fasedienol, and no safety signals were identified in laboratory values, ECGs, physical exams, or vital signs.¹

On efficacy measures, baseline mean scores on the Liebowitz Social Anxiety Scale indicated very severe social anxiety at study entry (99.3, n=320)¹, and mean improvement grew from 20.2 points at Month 1 to 31.4 points by Month 4, with the share of patients achieving at least a 20-point gain rising from 44 percent to 65 percent over that period.¹ On the Social Phobia Inventory, mean improvement rose from 10.5 points at Month 1 to 14.9 points at Month 4.¹

Notably, the company closed the extension study in July 2026 for business reasons before the data cutoff, so not all participants reached the four-month mark.¹ Vistagen said it is preparing to meet with the FDA during the current quarter to discuss a proposed new registrational Phase 3 trial of fasedienol in social anxiety disorder.¹