---
schema_version: "secwatch.filing_event.v1"
accession: "0000950170-24-106614"
form_type: "8-K"
ticker: "APVO"
cik: "0001671584"
company_name: "Aptevo Therapeutics Inc."
filed_at: "2024-09-16T23:59:59+00:00"
generated_at: "2026-05-31T04:37:21.529531+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.6
calibrated_materiality_score: 0.6
confidence: "high"
source: SEC EDGAR
---

# Aptevo/Alligator Phase 1 ALG.APV-527 trial: 60% stable disease, 11+ month duration in breast cancer

## Summary
- Phase 1 data presented at ESMO: 9 of 15 evaluable patients (60%) achieved stable disease across solid tumors.
- Breast cancer patient with progressive disease at entry achieved SD for >11 months and dose-escalated twice.
- Colon cancer patient with sustained SD remains on study for over 4 months.
- No maximum tolerated dose identified; safety profile positive across all cohorts.
- Serum concentrations consistent with dose and preclinical predictions; biomarker analyses confirm biological activity.

## SEC filing metadata
- accession: 0000950170-24-106614
- form_type: 8-K
- ticker: APVO
- cik: 0001671584
- company_name: Aptevo Therapeutics Inc.
- filed_at: 2024-09-16T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.6
- calibrated_materiality_score: 0.6
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1671584/000095017024106614/0000950170-24-106614-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1671584/000095017024106614/apvo-20240916.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0000950170-24-106614
- JSON: https://secwatch.observer/filing/0000950170-24-106614.json
- Plain text: https://secwatch.observer/filing/0000950170-24-106614.txt

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