---
schema_version: "secwatch.filing_event.v1"
accession: "0001104659-22-028113"
form_type: "8-K"
ticker: "PTGX"
cik: "0001377121"
company_name: "Protagonist Therapeutics, Inc"
filed_at: "2022-02-28T23:59:59+00:00"
generated_at: "2026-06-27T03:31:05.884877+00:00"
event_type: "earnings"
sentiment: "neutral"
materiality_score: 0.65
calibrated_materiality_score: 0.65
confidence: "high"
source: SEC EDGAR
---

# Protagonist reports Q4 2021 net loss $36.9M; cash $326.9M; rusfertide Phase 3 to start Q1 2022

## Summary
- Net loss Q4 2021 $36.9M ($0.77/share) vs $18.9M ($0.48/share) in Q4 2020; full year loss $125.6M ($2.71/share) vs $66.2M ($1.92/share).
- Cash, equivalents and marketable securities $326.9M as of Dec 31, 2021; expected to fund operations through 2024.
- Phase 3 VERIFY study of rusfertide in polycythemia vera to initiate Q1 2022; topline PN-943 Phase 2 UC data expected Q2 2022.
- Phase 2b FRONTIER 1 study of PN-235 in plaque psoriasis initiated; $25M milestone due upon dosing third patient.
- R&D expenses Q4 2021 $38.4M (vs $19.5M); full year $126.0M (vs $74.5M) on advancing pipeline and employee costs.

## SEC filing metadata
- accession: 0001104659-22-028113
- form_type: 8-K
- ticker: PTGX
- cik: 0001377121
- company_name: Protagonist Therapeutics, Inc
- filed_at: 2022-02-28T23:59:59+00:00
- event_type: earnings
- sentiment: neutral
- materiality_score: 0.65
- calibrated_materiality_score: 0.65
- confidence: high
- sec_items: 2.02, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1377121/000110465922028113/0001104659-22-028113-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1377121/000110465922028113/tm227855d1_8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001104659-22-028113
- JSON: https://secwatch.observer/filing/0001104659-22-028113.json
- Plain text: https://secwatch.observer/filing/0001104659-22-028113.txt

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