---
schema_version: "secwatch.filing_event.v1"
accession: "0000950170-22-013078"
form_type: "8-K"
ticker: "STRO"
cik: "0001382101"
company_name: "SUTRO BIOPHARMA, INC."
filed_at: "2022-07-26T23:59:59+00:00"
generated_at: "2026-06-24T08:38:45.576983+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.55
calibrated_materiality_score: 0.55
confidence: "high"
source: SEC EDGAR
---

# Sutro Biopharma receives $10M milestone from Merck after first patient dosed in Phase 1 collaboration study

## Summary
- Merck pays Sutro $10.0 million milestone following first patient dosing in Phase 1 study of a collaboration candidate.
- No other financial terms or guidance disclosed; collaboration continues.
- Specific investigational candidate not named in the filing.
- Milestone payment triggers positive cash inflow for Sutro's development programs.

## SEC filing metadata
- accession: 0000950170-22-013078
- form_type: 8-K
- ticker: STRO
- cik: 0001382101
- company_name: SUTRO BIOPHARMA, INC.
- filed_at: 2022-07-26T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.55
- calibrated_materiality_score: 0.55
- confidence: high
- sec_items: 8.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1382101/000095017022013078/0000950170-22-013078-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1382101/000095017022013078/stro-20220726.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0000950170-22-013078
- JSON: https://secwatch.observer/filing/0000950170-22-013078.json
- Plain text: https://secwatch.observer/filing/0000950170-22-013078.txt

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