---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-25-311276"
form_type: "8-K"
ticker: "ACLX"
cik: "0001786205"
company_name: "Arcellx, Inc."
filed_at: "2025-12-08T23:59:59+00:00"
generated_at: "2026-05-16T14:00:51.335800+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.85
calibrated_materiality_score: 0.85
confidence: "high"
source: SEC EDGAR
---

# Arcellx: anito-cel achieves 96% ORR, 74% CR/sCR in pivotal RRMM study

## Summary
- 96% ORR (112/117) and 74% CR/sCR (86/117); 95% MRD negativity (91/96) at 10^-5 sensitivity.
- 12-month PFS 82.1%, OS 94.0%; 24-month PFS 61.7%, OS 83.0% in 4L+ triple/penta-refractory patients.
- No delayed neurotoxicities (Parkinsonism, cranial nerve palsies, Guillain-Barré) observed; all patients dosed >12 months.
- Company reiterates planned 2026 commercial launch; building commercial and medical affairs organization.
- Data presented at ASH; BLA submission underway with Oct 2025 data cutoff.

## SEC filing metadata
- accession: 0001193125-25-311276
- form_type: 8-K
- ticker: ACLX
- cik: 0001786205
- company_name: Arcellx, Inc.
- filed_at: 2025-12-08T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.85
- calibrated_materiality_score: 0.85
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1786205/000119312525311276/0001193125-25-311276-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1786205/000119312525311276/d89813d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-25-311276
- JSON: https://secwatch.observer/filing/0001193125-25-311276.json
- Plain text: https://secwatch.observer/filing/0001193125-25-311276.txt

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