---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-25-142725"
form_type: "8-K"
ticker: "PRTA"
cik: "0001559053"
company_name: "PROTHENA CORP PUBLIC LTD CO"
filed_at: "2025-06-18T23:59:59+00:00"
generated_at: "2026-05-19T02:55:08.877359+00:00"
event_type: "leadership"
sentiment: "negative"
materiality_score: 0.78
calibrated_materiality_score: 0.78
confidence: "high"
source: SEC EDGAR
---

# Prothena cuts 63% of workforce, expects $16-20M severance costs; two C-suite execs to leave Aug 1

## Summary
- Workforce reduction of ~63% to cut operating costs; substantially complete by Q4 2025.
- Expected severance and benefits $16-20M plus non-cash stock option acceleration.
- Chief Regulatory Officer Carol D. Karp and Chief People Officer David A. Ford to depart Aug 1, 2025.
- Follows May 23 decision to discontinue birtamimab development.

## SEC filing metadata
- accession: 0001193125-25-142725
- form_type: 8-K
- ticker: PRTA
- cik: 0001559053
- company_name: PROTHENA CORP PUBLIC LTD CO
- filed_at: 2025-06-18T23:59:59+00:00
- event_type: leadership
- sentiment: negative
- materiality_score: 0.78
- calibrated_materiality_score: 0.78
- confidence: high
- sec_items: 2.05, 5.02
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1559053/000119312525142725/0001193125-25-142725-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1559053/000119312525142725/d945146d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-25-142725
- JSON: https://secwatch.observer/filing/0001193125-25-142725.json
- Plain text: https://secwatch.observer/filing/0001193125-25-142725.txt

## Key facts
- Executive change
  Carol D. Karp was terminated as Chief Regulatory Officer at PROTHENA CORP PUBLIC LTD CO.
  - Action: terminated
  - Role: Chief Regulatory Officer
  source text: On June 18, 2025, the Company announced that in connection with the workforce reduction, the employment of Carol D. Karp, the Company’s Chief Regulatory Officer, and David A. Ford, the Company’s Chief People Officer, will terminate effective August 1, 2025.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1559053/000119312525142725/0001193125-25-142725-index.htm
- Executive change
  David A. Ford was terminated as Chief People Officer at PROTHENA CORP PUBLIC LTD CO.
  - Action: terminated
  - Role: Chief People Officer
  source text: On June 18, 2025, the Company announced that in connection with the workforce reduction, the employment of Carol D. Karp, the Company’s Chief Regulatory Officer, and David A. Ford, the Company’s Chief People Officer, will terminate effective August 1, 2025.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1559053/000119312525142725/0001193125-25-142725-index.htm
- Restructurings & Charges
  PROTHENA CORP PUBLIC LTD CO announced a restructuring with charges of approximately $16 to $20 million (approximate 63% reduction in its workforce).
  - Type: restructuring
  - Charge: approximately $16 to $20 million
  - Headcount: approximate 63% reduction in its workforce
  source text: periods will be extended, pursuant to the terms of the option award agreements under which those stock options were granted. The Company expects to recognize approximately $16 to $20 million in total for severance and related benefits for employees laid off under the reduction in workforce and non-cash share-based compensation expense related to the
  evidence_url: https://www.sec.gov/Archives/edgar/data/1559053/000119312525142725/0001193125-25-142725-index.htm

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