---
schema_version: "secwatch.filing_event.v1"
accession: "0001171843-25-003854"
form_type: "8-K"
ticker: "APTOF"
cik: "0000882361"
company_name: "Aptose Biosciences Inc."
filed_at: "2025-06-12T23:59:59+00:00"
generated_at: "2026-05-19T12:01:44.975853+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.55
calibrated_materiality_score: 0.55
confidence: "high"
source: SEC EDGAR
---

# Aptose reports safety, CRs, MRD negativity in TUSCANY triplet for newly diagnosed AML

## Summary
- Ten newly diagnosed AML patients dosed in TUS+VEN+AZA triplet at 40, 80, 120 mg TUS; no DLTs observed.
- At 40 mg, 3 of 4 patients achieved CRs and MRD negativity, including FLT3-ITD, FLT3-WT, and TP53/CK.
- At 80 mg, all 3 patients achieved composite CRs (CR/CRi); one TP53-mutated/CK patient had early CRi.
- No treatment-related deaths; all 10 subjects remain alive; no prolonged myelosuppression or QT prolongation.
- Data presented at EHA 2025; TUS+VEN+AZA well-tolerated with standard of care dosing; enrollment ongoing.

## SEC filing metadata
- accession: 0001171843-25-003854
- form_type: 8-K
- ticker: APTOF
- cik: 0000882361
- company_name: Aptose Biosciences Inc.
- filed_at: 2025-06-12T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.55
- calibrated_materiality_score: 0.55
- confidence: high
- sec_items: 7.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/882361/000117184325003854/0001171843-25-003854-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/882361/000117184325003854/f8k_061125.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001171843-25-003854
- JSON: https://secwatch.observer/filing/0001171843-25-003854.json
- Plain text: https://secwatch.observer/filing/0001171843-25-003854.txt

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