---
schema_version: "secwatch.filing_event.v1"
accession: "0001559053-25-000003"
form_type: "8-K"
ticker: "PRTA"
cik: "0001559053"
company_name: "PROTHENA CORP PUBLIC LTD CO"
filed_at: "2025-02-20T23:59:59+00:00"
generated_at: "2026-05-26T08:44:31.690074+00:00"
event_type: "earnings"
sentiment: "neutral"
materiality_score: 0.7
calibrated_materiality_score: 0.7
confidence: "high"
source: SEC EDGAR
---

# Prothena reports FY2024 net loss $122.3M; cash $472.2M; AFFIRM-AL topline expected Q2 2025

## Summary
- Net loss per share Q4 $1.08, FY2024 $2.27; total revenue FY2024 $135.2M (up from $91.4M prior year).
- Cash $472.2M at Dec 31, 2024, no debt; 2025 guidance: net cash burn $168-175M, year-end cash ≈$301M.
- Confirmatory Phase 3 AFFIRM-AL (birtamimab) topline results expected Q2 2025; SPA with FDA, primary endpoint all-cause mortality.
- PRX012 Phase 1 ASCENT readouts starting mid-2025; BMS started Phase 2 for BMS-986446; $80M received for PRX019 license.
- Roche's prasinezumab Phase 2b PADOVA missed primary endpoint but showed trends; Roche to discuss next steps with health authorities.

## SEC filing metadata
- accession: 0001559053-25-000003
- form_type: 8-K
- ticker: PRTA
- cik: 0001559053
- company_name: PROTHENA CORP PUBLIC LTD CO
- filed_at: 2025-02-20T23:59:59+00:00
- event_type: earnings
- sentiment: neutral
- materiality_score: 0.7
- calibrated_materiality_score: 0.7
- confidence: high
- sec_items: 2.02, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1559053/000155905325000003/0001559053-25-000003-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1559053/000155905325000003/prta-20250220.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001559053-25-000003
- JSON: https://secwatch.observer/filing/0001559053-25-000003.json
- Plain text: https://secwatch.observer/filing/0001559053-25-000003.txt

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