---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-24-153625"
form_type: "8-K"
ticker: "ANNX"
cik: "0001528115"
company_name: "Annexon, Inc."
filed_at: "2024-06-04T23:59:59+00:00"
generated_at: "2026-06-01T06:31:42.839330+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.85
calibrated_materiality_score: 0.85
confidence: "high"
source: SEC EDGAR
---

# Annexon Phase 3 GBS trial meets primary endpoint; ANX005 shows 2.4-fold improvement on GBS-DS at week 8

## Summary
- Phase 3 trial met primary endpoint: single infusion of ANX005 30 mg/kg achieved 2.4-fold improvement on GBS-DS at week 8 (p=0.0058).
- Key secondary endpoints met: 28 fewer days on ventilation (p=0.0356), 31-day reduction in time to walk independently (p=0.0211), and early muscle strength gains.
- ANX005 was generally well-tolerated; most adverse events mild-to-moderate, no drug-related deaths or serious infections.
- RWE comparability protocol initiated with IGOS; BLA submission and RWE data expected first half 2025.
- GBS affects >22,000 hospitalized annually in U.S./Europe; no FDA-approved treatments currently.

## SEC filing metadata
- accession: 0001193125-24-153625
- form_type: 8-K
- ticker: ANNX
- cik: 0001528115
- company_name: Annexon, Inc.
- filed_at: 2024-06-04T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.85
- calibrated_materiality_score: 0.85
- confidence: high
- sec_items: 7.01, 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1528115/000119312524153625/0001193125-24-153625-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1528115/000119312524153625/d838099d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-24-153625
- JSON: https://secwatch.observer/filing/0001193125-24-153625.json
- Plain text: https://secwatch.observer/filing/0001193125-24-153625.txt

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