---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-25-100859"
form_type: "8-K"
ticker: null
cik: "0002040807"
company_name: "Metsera, Inc."
filed_at: "2025-04-28T23:59:59+00:00"
generated_at: "2026-05-23T05:17:35.112460+00:00"
event_type: "leadership"
sentiment: "neutral"
materiality_score: 0.5
calibrated_materiality_score: 0.5
confidence: "high"
source: SEC EDGAR
---

# Metsera appoints Jon Stonehouse to Board and Matt Lang as Chief Legal Officer

## Summary
- Jon P. Stonehouse appointed to Board (Class III) and Audit Committee effective April 28, 2025.
- Matthew Lang appointed Chief Legal Officer and Secretary; previously CBO/CLO at Lyell Immunopharma.
- Stonehouse receives option award vesting in 36 equal monthly installments under director comp plan.
- Stonehouse is CEO of BioCryst Pharmaceuticals; brings M&A and pharma leadership experience.
- Lang's background includes executive roles at Myovant Sciences and Gilead Sciences.

## SEC filing metadata
- accession: 0001193125-25-100859
- form_type: 8-K
- cik: 0002040807
- company_name: Metsera, Inc.
- filed_at: 2025-04-28T23:59:59+00:00
- event_type: leadership
- sentiment: neutral
- materiality_score: 0.5
- calibrated_materiality_score: 0.5
- confidence: high
- sec_items: 5.02, 7.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/2040807/000119312525100859/0001193125-25-100859-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/2040807/000119312525100859/d116647d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-25-100859
- JSON: https://secwatch.observer/filing/0001193125-25-100859.json
- Plain text: https://secwatch.observer/filing/0001193125-25-100859.txt

## Key facts
- Executive change
  Jon P. Stonehouse was appointed as Director at Metsera, Inc..
  - Action: appointed
  - Role: Director
  source text: On April 28, 2025, the Board of Directors (the “Board”) of Metsera, Inc. (the “Company”) appointed Jon P. Stonehouse to the Company’s Board, effective immediately.
  evidence_url: https://www.sec.gov/Archives/edgar/data/2040807/000119312525100859/0001193125-25-100859-index.htm

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