---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-26-045649"
form_type: "8-K"
ticker: "UPB"
cik: "0002022626"
company_name: "Upstream Bio, Inc."
filed_at: "2026-02-11T23:59:59+00:00"
generated_at: "2026-05-16T03:24:27.073443+00:00"
event_type: "other_material"
sentiment: "neutral"
materiality_score: 0.65
calibrated_materiality_score: 0.65
confidence: "low"
source: SEC EDGAR
---

# Upstream Bio reports preliminary cash of $341.5M; Phase 2 VALIANT top-line data released

## Summary
- Preliminary unaudited cash, cash equivalents and short-term investments of $341.5M as of Dec 31, 2025.
- Top-line results from Phase 2 VALIANT trial of verekitug in severe asthma presented in webcast; details in investor presentation.
- Year-end 2025 financial close not yet completed; full results to be included in Form 10-K.

## SEC filing metadata
- accession: 0001193125-26-045649
- form_type: 8-K
- ticker: UPB
- cik: 0002022626
- company_name: Upstream Bio, Inc.
- filed_at: 2026-02-11T23:59:59+00:00
- event_type: other_material
- sentiment: neutral
- materiality_score: 0.65
- calibrated_materiality_score: 0.65
- confidence: low
- sec_items: 2.02, 7.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/2022626/000119312526045649/0001193125-26-045649-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/2022626/000119312526045649/d103888d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-26-045649
- JSON: https://secwatch.observer/filing/0001193125-26-045649.json
- Plain text: https://secwatch.observer/filing/0001193125-26-045649.txt

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