---
schema_version: "secwatch.filing_event.v1"
accession: "0001370053-25-000052"
form_type: "8-K"
ticker: "ANAB"
cik: "0001370053"
company_name: "ANAPTYSBIO, INC"
filed_at: "2025-06-03T23:59:59+00:00"
generated_at: "2026-05-20T01:12:37.839159+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.9
calibrated_materiality_score: 0.9
confidence: "high"
source: SEC EDGAR
---

# AnaptysBio rosnilimab Phase 2b RA data shows best-in-disease profile with JAK-like efficacy

## Summary
- 424-patient Phase 2b trial: rosnilimab achieved JAK-like efficacy on CDAI LDA, remission, and ACR70 through six months.
- Favorable safety: no treatment-related SAEs, <2% discontinuation due to AEs, low injection site reactions.
- Responses durable for at least 2 months off drug; pain VAS improved ~50 points from baseline ~65 to ~15.
- 69% of patients achieved CDAI LDA by Week 14; max response rates not yet observed due to strict continuation criteria.

## SEC filing metadata
- accession: 0001370053-25-000052
- form_type: 8-K
- ticker: ANAB
- cik: 0001370053
- company_name: ANAPTYSBIO, INC
- filed_at: 2025-06-03T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.9
- calibrated_materiality_score: 0.9
- confidence: high
- sec_items: 7.01, 8.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1370053/000137005325000052/0001370053-25-000052-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1370053/000137005325000052/anab-20250603.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001370053-25-000052
- JSON: https://secwatch.observer/filing/0001370053-25-000052.json
- Plain text: https://secwatch.observer/filing/0001370053-25-000052.txt

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