---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-22-308821"
form_type: "8-K"
ticker: "DNTH"
cik: "0001690585"
company_name: "Dianthus Therapeutics, Inc. /DE/"
filed_at: "2022-12-20T23:59:59+00:00"
generated_at: "2026-06-21T01:49:02.081994+00:00"
event_type: "other_material"
sentiment: "negative"
materiality_score: 0.8
calibrated_materiality_score: 0.8
confidence: "high"
source: SEC EDGAR
---

# Magenta stops MGTA-117 Cohort 4 dosing after two DLTs; to continue at Cohort 3

## Summary
- Three participants dosed in Cohort 4 (0.13 mg/kg); two had dose-limiting toxicities (respiratory SAEs).
- First DLT was Grade 4 respiratory SAE; second DLT triggered pre-specified stopping rules.
- No DLTs observed in fifteen participants across first three cohorts.
- Three of four Cohort 3 participants with paired samples showed cancer blast depletion in blood and bone marrow.
- Magenta reported first DLT to FDA; plans to enroll more patients at Cohort 3 (0.08 mg/kg).

## SEC filing metadata
- accession: 0001193125-22-308821
- form_type: 8-K
- ticker: DNTH
- cik: 0001690585
- company_name: Dianthus Therapeutics, Inc. /DE/
- filed_at: 2022-12-20T23:59:59+00:00
- event_type: other_material
- sentiment: negative
- materiality_score: 0.8
- calibrated_materiality_score: 0.8
- confidence: high
- sec_items: 7.01, 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1690585/000119312522308821/0001193125-22-308821-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1690585/000119312522308821/d434259d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-22-308821
- JSON: https://secwatch.observer/filing/0001193125-22-308821.json
- Plain text: https://secwatch.observer/filing/0001193125-22-308821.txt

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