---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-24-003972"
form_type: "8-K"
ticker: "PRTA"
cik: "0001559053"
company_name: "PROTHENA CORP PUBLIC LTD CO"
filed_at: "2024-01-08T23:59:59+00:00"
generated_at: "2026-06-07T02:16:02.809942+00:00"
event_type: "other_material"
sentiment: "neutral"
materiality_score: 0.6
calibrated_materiality_score: 0.6
confidence: "high"
source: SEC EDGAR
---

# Prothena reports $621M cash at year-end 2023; pipeline updates on PRX012, PRX123, birtamimab

## Summary
- Cash, cash equivalents, and restricted cash ~$621M as of Dec 31, 2023; sufficient capital beyond ongoing trials.
- PRX012 (Alzheimer's): Phase 1 data supports once-monthly dosing; dose escalation to 200-400mg underway.
- PRX123 (Alzheimer's vaccine): IND cleared and Fast Track designation; Phase 1 timeline update expected in 2024.
- Birtamimab (AL amyloidosis): Phase 3 AFFIRM-AL enrollment on track; topline results expected 4Q24-2Q25.
- Partnered programs with BMS, Roche, Novo Nordisk remain on track; BMS-986446 moving to Phase 2 in 1H24.

## SEC filing metadata
- accession: 0001193125-24-003972
- form_type: 8-K
- ticker: PRTA
- cik: 0001559053
- company_name: PROTHENA CORP PUBLIC LTD CO
- filed_at: 2024-01-08T23:59:59+00:00
- event_type: other_material
- sentiment: neutral
- materiality_score: 0.6
- calibrated_materiality_score: 0.6
- confidence: high
- sec_items: 2.02, 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1559053/000119312524003972/0001193125-24-003972-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1559053/000119312524003972/d707357d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-24-003972
- JSON: https://secwatch.observer/filing/0001193125-24-003972.json
- Plain text: https://secwatch.observer/filing/0001193125-24-003972.txt

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