---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-23-160348"
form_type: "8-K"
ticker: "TSHA"
cik: "0001806310"
company_name: "Taysha Gene Therapies, Inc."
filed_at: "2023-06-05T23:59:59+00:00"
generated_at: "2026-06-14T07:29:52.901827+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.75
calibrated_materiality_score: 0.75
confidence: "high"
source: SEC EDGAR
---

# Taysha doses first patient with TSHA-102 in Phase 1/2 REVEAL trial for Rett syndrome

## Summary
- First adult patient received TSHA-102, an AAV9 gene therapy using miRARE technology to regulate MECP2.
- Phase 1/2 REVEAL trial: open-label, dose-escalation (5x10^14 vg then 1x10^15 vg) and dose-expansion in adult females.
- Initial safety data from first patient expected at R&D Day on June 28, 2023.
- Study conducted at CHU Sainte-Justine in Montreal, Canada; independent data monitoring committee will review safety at ~6 weeks.
- First time a gene therapy is evaluated clinically for Rett syndrome, per Taysha management.

## SEC filing metadata
- accession: 0001193125-23-160348
- form_type: 8-K
- ticker: TSHA
- cik: 0001806310
- company_name: Taysha Gene Therapies, Inc.
- filed_at: 2023-06-05T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.75
- calibrated_materiality_score: 0.75
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1806310/000119312523160348/0001193125-23-160348-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1806310/000119312523160348/d513071d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-23-160348
- JSON: https://secwatch.observer/filing/0001193125-23-160348.json
- Plain text: https://secwatch.observer/filing/0001193125-23-160348.txt

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