---
schema_version: "secwatch.filing_event.v1"
accession: "0001104659-26-019658"
form_type: "8-K"
ticker: "PTGX"
cik: "0001377121"
company_name: "Protagonist Therapeutics, Inc"
filed_at: "2026-02-25T23:59:59+00:00"
generated_at: "2026-05-16T00:11:31.776988+00:00"
event_type: "earnings"
sentiment: "negative"
materiality_score: 0.75
calibrated_materiality_score: 0.75
confidence: "high"
source: SEC EDGAR
---

# Protagonist Q4 net loss $44.4M ($0.69/share); rusfertide opt-out expected Q2 2026

## Summary
- Q4 2025 net loss $44.4M ($0.69 per share) vs Q4 2024 net income $131.7M ($2.11 per share); FY2025 loss $130.1M ($2.05) vs FY2024 income $275.2M ($4.47).
- License revenue fell to $7.4M in Q4 2025 from $170.6M in Q4 2024; FY2025 revenue $46.0M from $434.4M, due to lower milestones.
- Cash, equivalents and marketable securities $646M as of Dec 31, 2025; provides runway through at least end of 2028.
- Rusfertide NDA filed; company expects to opt out of the 50:50 profit/loss sharing with Takeda in a 90-day window opening in Q2 2026.
- ICOTYDE regulatory decision anticipated in 2026 with potential launch this year; PN-881 Phase 1 completion by mid-2026; new preclinical candidates added.

## SEC filing metadata
- accession: 0001104659-26-019658
- form_type: 8-K
- ticker: PTGX
- cik: 0001377121
- company_name: Protagonist Therapeutics, Inc
- filed_at: 2026-02-25T23:59:59+00:00
- event_type: earnings
- sentiment: negative
- materiality_score: 0.75
- calibrated_materiality_score: 0.75
- confidence: high
- sec_items: 2.02, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1377121/000110465926019658/0001104659-26-019658-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1377121/000110465926019658/tm267184d1_8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001104659-26-019658
- JSON: https://secwatch.observer/filing/0001104659-26-019658.json
- Plain text: https://secwatch.observer/filing/0001104659-26-019658.txt

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