---
schema_version: "secwatch.filing_event.v1"
accession: "0001628280-26-027930"
form_type: "8-K"
ticker: "VTGN"
cik: "0001411685"
company_name: "Vistagen Therapeutics, Inc."
filed_at: "2026-04-28T23:59:59+00:00"
generated_at: "2026-05-15T02:48:01.960191+00:00"
event_type: "regulatory"
sentiment: "positive"
materiality_score: 0.65
calibrated_materiality_score: 0.65
confidence: "high"
source: SEC EDGAR
---

# Vistagen gets FDA 'Study May Proceed' letter for refisolone nasal spray in menopausal hot flashes

## Summary
- FDA allows Vistagen to pursue further Phase 2 clinical development of refisolone in U.S. for vasomotor symptoms due to menopause.
- Exploratory Phase 2a study (N=36): refisolone reduced hot flash frequency by 80% vs 36% placebo; effect seen by week 1 (p<.001).
- Refisolone was well-tolerated with no serious drug-related adverse events in the Phase 2a study conducted in Mexico.
- Company cites large unmet need: ~75% of women in America experience hot flashes during menopausal transition.

## SEC filing metadata
- accession: 0001628280-26-027930
- form_type: 8-K
- ticker: VTGN
- cik: 0001411685
- company_name: Vistagen Therapeutics, Inc.
- filed_at: 2026-04-28T23:59:59+00:00
- event_type: regulatory
- sentiment: positive
- materiality_score: 0.65
- calibrated_materiality_score: 0.65
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1411685/000162828026027930/0001628280-26-027930-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1411685/000162828026027930/vtgn-20260422.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001628280-26-027930
- JSON: https://secwatch.observer/filing/0001628280-26-027930.json
- Plain text: https://secwatch.observer/filing/0001628280-26-027930.txt

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.