---
schema_version: "secwatch.filing_event.v1"
accession: "0001171843-25-006472"
form_type: "8-K"
ticker: "APTOF"
cik: "0000882361"
company_name: "Aptose Biosciences Inc."
filed_at: "2025-10-16T23:59:59+00:00"
generated_at: "2026-05-17T03:39:06.192216+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.75
calibrated_materiality_score: 0.75
confidence: "high"
source: SEC EDGAR
---

# Aptose tuspetinib combo achieves 100% CR/CRh at higher doses in newly diagnosed AML trial

## Summary
- TUS+VEN+AZA achieved 100% CR/CRh (6/6) at 80mg and 120mg doses, exceeding 66% expected from VEN+AZA alone.
- CR/CRh in 7/8 (88%) FLT3 wildtype AML; responses across TP53, RAS, FLT3-ITD mutations.
- No dose-limiting toxicities, QTc prolongation, differentiation syndrome, or prolonged myelosuppression seen.
- Dosing at 160mg TUS level now ongoing; trial enrolling 18-24 patients by end of 2025.

## SEC filing metadata
- accession: 0001171843-25-006472
- form_type: 8-K
- ticker: APTOF
- cik: 0000882361
- company_name: Aptose Biosciences Inc.
- filed_at: 2025-10-16T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.75
- calibrated_materiality_score: 0.75
- confidence: high
- sec_items: 7.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/882361/000117184325006472/0001171843-25-006472-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/882361/000117184325006472/f8k_101525.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001171843-25-006472
- JSON: https://secwatch.observer/filing/0001171843-25-006472.json
- Plain text: https://secwatch.observer/filing/0001171843-25-006472.txt

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