---
schema_version: "secwatch.filing_event.v1"
accession: "0000950170-23-015323"
form_type: "8-K"
ticker: "STRO"
cik: "0001382101"
company_name: "SUTRO BIOPHARMA, INC."
filed_at: "2023-04-27T23:59:59+00:00"
generated_at: "2026-06-16T08:40:25.982467+00:00"
event_type: "leadership"
sentiment: "neutral"
materiality_score: 0.5
calibrated_materiality_score: 0.5
confidence: "high"
source: SEC EDGAR
---

# Sutro Biopharma CSO Dr. Trevor Hallam resigns, effective May 31, 2023

## Summary
- Dr. Trevor Hallam resigns as President of Research and Chief Scientific Officer effective May 31, 2023.
- Resignation is not due to any disagreement with management or the board.
- No successor has been announced.

## SEC filing metadata
- accession: 0000950170-23-015323
- form_type: 8-K
- ticker: STRO
- cik: 0001382101
- company_name: SUTRO BIOPHARMA, INC.
- filed_at: 2023-04-27T23:59:59+00:00
- event_type: leadership
- sentiment: neutral
- materiality_score: 0.5
- calibrated_materiality_score: 0.5
- confidence: high
- sec_items: 5.02
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1382101/000095017023015323/0000950170-23-015323-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1382101/000095017023015323/stro-20230424.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0000950170-23-015323
- JSON: https://secwatch.observer/filing/0000950170-23-015323.json
- Plain text: https://secwatch.observer/filing/0000950170-23-015323.txt

## Key facts
- Executive change
  Trevor Hallam resigned as President of Research and Chief Scientific Officer at SUTRO BIOPHARMA, INC..
  - Action: resigned
  - Role: President of Research and Chief Scientific Officer
  source text: On April 24, 2023, Dr. Trevor Hallam notified Sutro Biopharma, Inc. (the “ Company ”) that he will resign from his role as President of Research and Chief Scientific Officer of the Company, effective May 31, 2023.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1382101/000095017023015323/0000950170-23-015323-index.htm

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