---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-26-249763"
form_type: "8-K"
ticker: "JBIO"
cik: "0001798749"
company_name: "Jade Biosciences, Inc."
filed_at: "2026-06-01T11:55:09+00:00"
generated_at: "2026-06-01T12:00:52.710902+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.75
calibrated_materiality_score: 0.75
confidence: "high"
source: SEC EDGAR
---

# Jade Biosciences reports Phase 1 interim data: JADE101 shows ~70% IgA reduction, favorable safety, differentiated PK

## Summary
- Mean IgA reduction ~70% from baseline, sustained at 12 weeks with single 700 mg dose; steady-state simulation supports Q12W dosing.
- JADE101 estimated 379-fold more potent than sibeprenlimab and 26-fold more potent than povetacicept in IgA-lowering.
- Favorable safety: no serious AEs, no discontinuations, no hypogammaglobulinemia; most common AEs were headache (25%), URTI (21.9%).
- Half-life at steady state ~8.7x longer than povetacicept and ~2.6x longer than sibeprenlimab, supporting convenient dosing (4 injections/year).
- Phase 2 JUNIPER trial ongoing; registrational Phase 3 planned for H1 2027.

## SEC filing metadata
- accession: 0001193125-26-249763
- form_type: 8-K
- ticker: JBIO
- cik: 0001798749
- company_name: Jade Biosciences, Inc.
- filed_at: 2026-06-01T11:55:09+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.75
- calibrated_materiality_score: 0.75
- confidence: high
- sec_items: 7.01, 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1798749/000119312526249763/0001193125-26-249763-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1798749/000119312526249763/d124589d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-26-249763
- JSON: https://secwatch.observer/filing/0001193125-26-249763.json
- Plain text: https://secwatch.observer/filing/0001193125-26-249763.txt

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