---
schema_version: "secwatch.filing_event.v1"
accession: "0001628280-25-045157"
form_type: "8-K"
ticker: "CCCC"
cik: "0001662579"
company_name: "C4 Therapeutics, Inc."
filed_at: "2025-10-16T23:59:59+00:00"
generated_at: "2026-05-17T03:34:18.017555+00:00"
event_type: "other_material"
sentiment: "neutral"
materiality_score: 0.4
calibrated_materiality_score: 0.4
confidence: "low"
source: SEC EDGAR
---

# C4 Therapeutics posts Phase 1 cemsidomide data in RRMM; terminates TD Cowen ATM prospectus

## Summary
- Posted Phase 1 data for cemsidomide + dex in relapsed/refractory multiple myeloma; presentation on IR website.
- Terminated sales agreement prospectus with TD Cowen effective Oct 16, 2025; underlying agreement remains in effect.
- Previously issued 3,769,483 shares under TD Cowen ATM for gross proceeds of $9.6M as of June 30, 2025.

## SEC filing metadata
- accession: 0001628280-25-045157
- form_type: 8-K
- ticker: CCCC
- cik: 0001662579
- company_name: C4 Therapeutics, Inc.
- filed_at: 2025-10-16T23:59:59+00:00
- event_type: other_material
- sentiment: neutral
- materiality_score: 0.4
- calibrated_materiality_score: 0.4
- confidence: low
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1662579/000162828025045157/0001628280-25-045157-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1662579/000162828025045157/cccc-20251016.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001628280-25-045157
- JSON: https://secwatch.observer/filing/0001628280-25-045157.json
- Plain text: https://secwatch.observer/filing/0001628280-25-045157.txt

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