---
schema_version: "secwatch.filing_event.v1"
accession: "0000950170-23-066112"
form_type: "8-K"
ticker: "STRO"
cik: "0001382101"
company_name: "SUTRO BIOPHARMA, INC."
filed_at: "2023-11-27T23:59:59+00:00"
generated_at: "2026-06-07T21:24:34.604198+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.75
calibrated_materiality_score: 0.75
confidence: "high"
source: SEC EDGAR
---

# Vaxcyte exercises option, pays Sutro $50M; manufacturing rights agreement effective

## Summary
- Vaxcyte exercised option on Nov 21, 2023, paying $50M cash as first installment.
- Vaxcyte must pay an additional $25M within six months of exercise date.
- Up to $60M in additional regulatory milestone payments could be paid to Sutro.
- Manufacturing Rights Agreement grants Vaxcyte exclusive, perpetual, royalty-free license to manufacture extract.
- Sutro can terminate if Vaxcyte breaches confidentiality or fails to pay; Vaxcyte can terminate on 60 days notice.

## SEC filing metadata
- accession: 0000950170-23-066112
- form_type: 8-K
- ticker: STRO
- cik: 0001382101
- company_name: SUTRO BIOPHARMA, INC.
- filed_at: 2023-11-27T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.75
- calibrated_materiality_score: 0.75
- confidence: high
- sec_items: 1.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1382101/000095017023066112/0000950170-23-066112-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1382101/000095017023066112/stro-20231121.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0000950170-23-066112
- JSON: https://secwatch.observer/filing/0000950170-23-066112.json
- Plain text: https://secwatch.observer/filing/0000950170-23-066112.txt

## Key facts
- Material Agreements
  SUTRO BIOPHARMA, INC. entered into Manufacturing Rights Agreement with Vaxcyte, Inc. valued at $50.0 million (effective 2023-11-21).
  - Action: entry
  - Agreement: license
  - Counterparty: Vaxcyte, Inc.
  - Value: $50.0 million
  - Effective: 2023-11-21
  source text: (the “Company”) entered into a letter agreement (the “Option Agreement”) with Vaxcyte, Inc. (“Vaxcyte”), under which the Company granted to Vaxcyte (i) authorization to enter into an agreement with an independent alternate contract manufacturing organization (“CMO”) to source cell-free extract solely for the products it licensed from the Company, allowing Vaxcyte to have direct oversight over financial and operational aspects of the relationship with the CMO; and (ii) a right, but not an obligation, to obtain certain exclusive rights to internally manufacture and/or source extract from certain CMOs and the right to independently develop and make improvements to extract for use in connection with the exploitation of certain vaccine compositions (the “Option”).
  evidence_url: https://www.sec.gov/Archives/edgar/data/1382101/000095017023066112/0000950170-23-066112-index.htm

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