Vistagen (Nasdaq: VTGN) released topline results from an exploratory Phase 2 repeat dose study of fasedienol nasal spray for the acute treatment of social anxiety disorder (SAD), according to a company statement.

The three-arm, multicenter, randomized, double-blind, placebo-controlled study enrolled 61 adult subjects and compared two sequential 3.2 µg doses of fasedienol administered ten minutes apart against a single 3.2 µg dose and placebo. The study was not designed to demonstrate statistically significant differences between treatment groups.

On the primary endpoint, mean change in subjective units of distress (SUDS) score, both active arms showed numerical separation from placebo but did not reach statistical significance. Pooled fasedienol produced a mean change of -15.0 versus -6.8 for placebo (p=0.10). The repeat dose arm showed -15.4 (p=0.17) and the single dose arm showed -14.7 (p=0.14).

In a prespecified subgroup analysis of patients with very severe SAD, defined by a baseline Liebowitz Social Anxiety Scale score of 95 or higher, pooled fasedienol achieved a nominally statistically significant result of -16.2 versus -1.6 for placebo (p=0.04). The single dose arm reached p=0.05, while the repeat dose arm produced p=0.08.

Responder rates on secondary endpoints, the Clinician Global Impression of Improvement and Patient Global Impression of Change, were higher for fasedienol than placebo across the full study population. In the repeat dose arm, responder rates were more than twice those observed with placebo.

The study met its safety objective. A second dose administered within ten minutes of the first produced safety and tolerability data comparable to single-dose administration, with no new safety findings.

"These results will help inform our discussions with the FDA regarding a potential registrational pathway for fasedienol," said Dr. Angel Angelov, Chief Medical Officer of Vistagen.

Because the study was not powered to demonstrate statistical significance, the company noted there is no assurance that the numerical trends observed will be replicated in future adequately powered trials.