---
schema_version: "secwatch.filing_event.v1"
accession: "0001213900-25-044875"
form_type: "8-K"
ticker: "OSTX"
cik: "0001795091"
company_name: "OS Therapies Inc"
filed_at: "2025-05-16T23:59:59+00:00"
generated_at: "2026-05-21T03:30:40.567197+00:00"
event_type: "earnings"
sentiment: "neutral"
materiality_score: 0.75
calibrated_materiality_score: 0.75
confidence: "high"
source: SEC EDGAR
---

# OS Therapies Q1 net op loss $3.876M; OST-HER2 BLA on track for Q3 2025

## Summary
- Net operating loss of $3.876M in Q1 2025 vs $1.490M in Q1 2024, due to trial closeout and regulatory prep costs.
- Net loss per share of $0.18 on 21.249M shares vs $0.25 on 5.991M shares in prior year period.
- Positive Phase 2b data for OST-HER2 in pediatric osteosarcoma; FDA Type D meeting feedback expected mid-June 2025.
- Company on track to file BLA for OST-HER2 in Q3 2025 for accelerated approval in osteosarcoma.
- Acquired three clinical-stage and eight preclinical listeria immunotherapy assets from Ayala Pharmaceuticals.

## SEC filing metadata
- accession: 0001213900-25-044875
- form_type: 8-K
- ticker: OSTX
- cik: 0001795091
- company_name: OS Therapies Inc
- filed_at: 2025-05-16T23:59:59+00:00
- event_type: earnings
- sentiment: neutral
- materiality_score: 0.75
- calibrated_materiality_score: 0.75
- confidence: high
- sec_items: 2.02, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1795091/000121390025044875/0001213900-25-044875-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1795091/000121390025044875/ea0242452-8k_ostherapies.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001213900-25-044875
- JSON: https://secwatch.observer/filing/0001213900-25-044875.json
- Plain text: https://secwatch.observer/filing/0001213900-25-044875.txt

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