---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-24-279038"
form_type: "8-K"
ticker: "ANNX"
cik: "0001528115"
company_name: "Annexon, Inc."
filed_at: "2024-12-16T23:59:59+00:00"
generated_at: "2026-05-29T02:53:34.327613+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.75
calibrated_materiality_score: 0.75
confidence: "high"
source: SEC EDGAR
---

# Annexon positive real-world evidence study of ANX005 in Guillain-Barré Syndrome shows benefit over IVIg/PE

## Summary
- ANX005 30 mg/kg showed faster improvement in muscle strength vs matched IVIg/PE cohort at week 1 (p<0.0001).
- Patients on ANX005 ~2x more likely to be in better health on GBS-Disability Scale at week 8 (p=0.0459).
- Fewer ANX005 patients required mechanical ventilation (15/79 vs 32/79, p=0.022); 12 fewer median days on ventilation and in ICU.
- Planned U.S. Biologics License Application submission for ANX005 in GBS in first half 2025.
- Study used propensity-score matching between Phase 3 patients (n=79) and IGOS global registry patients (n=79).

## SEC filing metadata
- accession: 0001193125-24-279038
- form_type: 8-K
- ticker: ANNX
- cik: 0001528115
- company_name: Annexon, Inc.
- filed_at: 2024-12-16T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.75
- calibrated_materiality_score: 0.75
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1528115/000119312524279038/0001193125-24-279038-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1528115/000119312524279038/d909577d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-24-279038
- JSON: https://secwatch.observer/filing/0001193125-24-279038.json
- Plain text: https://secwatch.observer/filing/0001193125-24-279038.txt

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