---
schema_version: "secwatch.filing_event.v1"
accession: "0001628280-25-047322"
form_type: "8-K"
ticker: "FHTX"
cik: "0001822462"
company_name: "Foghorn Therapeutics Inc."
filed_at: "2025-10-30T23:59:59+00:00"
generated_at: "2026-05-17T01:24:13.831691+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.6
calibrated_materiality_score: 0.6
confidence: "high"
source: SEC EDGAR
---

# Foghorn Therapeutics advances three degrader programs; ARID1B degrader selectively degrades ARID1B

## Summary
- Selective ARID1B degrader shows selective binding and degradation, potentially relevant in up to 5% of solid tumors (endometrial, gastric, bladder, NSCLC).
- Selective CBP degrader CBPd-171 advancing to non-GLP toxicology studies in Q4 2025; IND-ready in 2026 for EP300-mutant cancers and ER+ breast cancer.
- Selective EP300 degrader demonstrates efficacy in >70% of hematological malignancies and IMiD-resistant multiple myeloma without thrombocytopenia.
- All three programs leverage novel degrader technology to overcome historical challenges of high homology with ARID1A, CBP/EP300.
- Company hosting virtual investor event on October 30, 2025 at 12 p.m. ET to present data.

## SEC filing metadata
- accession: 0001628280-25-047322
- form_type: 8-K
- ticker: FHTX
- cik: 0001822462
- company_name: Foghorn Therapeutics Inc.
- filed_at: 2025-10-30T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.6
- calibrated_materiality_score: 0.6
- confidence: high
- sec_items: 7.01, 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1822462/000162828025047322/0001628280-25-047322-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1822462/000162828025047322/fhtx-20251030.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001628280-25-047322
- JSON: https://secwatch.observer/filing/0001628280-25-047322.json
- Plain text: https://secwatch.observer/filing/0001628280-25-047322.txt

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