---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-22-153616"
form_type: "8-K"
ticker: "TECX"
cik: "0001681087"
company_name: "Tectonic Therapeutic, Inc."
filed_at: "2022-05-18T23:59:59+00:00"
generated_at: "2026-06-25T10:00:50.314924+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.65
calibrated_materiality_score: 0.65
confidence: "high"
source: SEC EDGAR
---

# AVROBIO reports preclinical Pompe gene therapy data; >99% glycogen reduction in heart; trial start 2023

## Summary
- Median GAA enzyme activity in bone marrow reached 300-534 nmol/h/mg (p<0.005) vs 4-6 in normal mice eight months post-infusion.
- >99% glycogen reduction in heart with reversal of cardiac hypertrophy; >97% reduction in diaphragm, >85% in quadriceps.
- >95% glycogen reduction in brain and >99% in spinal cord; improved locomotor function and blood-brain barrier crossing.
- Stable engraftment at eight months with median vector copy numbers 1.9-3.6 per diploid genome; no clonal dominance observed.
- AVROBIO plans to engage regulators in 2022 and initiate a clinical trial for AVR-RD-03 in 2023.

## SEC filing metadata
- accession: 0001193125-22-153616
- form_type: 8-K
- ticker: TECX
- cik: 0001681087
- company_name: Tectonic Therapeutic, Inc.
- filed_at: 2022-05-18T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.65
- calibrated_materiality_score: 0.65
- confidence: high
- sec_items: 7.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1681087/000119312522153616/0001193125-22-153616-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1681087/000119312522153616/d322523d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-22-153616
- JSON: https://secwatch.observer/filing/0001193125-22-153616.json
- Plain text: https://secwatch.observer/filing/0001193125-22-153616.txt

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