---
schema_version: "secwatch.filing_event.v1"
accession: "0000950170-25-035482"
form_type: "8-K"
ticker: "ATRA"
cik: "0001604464"
company_name: "Atara Biotherapeutics, Inc."
filed_at: "2025-03-07T23:59:59+00:00"
generated_at: "2026-05-25T03:42:36.808707+00:00"
event_type: "earnings"
sentiment: "negative"
materiality_score: 0.85
calibrated_materiality_score: 0.85
confidence: "high"
source: SEC EDGAR
---

# Atara Q4 2024 net loss $12.7M; workforce cut 50%; pauses CAR-T programs; EBVALLO BLA resubmission ongoing

## Summary
- Net loss of $12.7M ($1.19/share) for Q4 2024 vs $60.5M loss in Q4 2023; full year loss $85.4M.
- Cash and equivalents $42.5M at Dec 31, 2024; entered non-binding term sheet for up to $15M equity line with Redmile Group.
- Workforce reduced ~50%, retaining ~35 personnel to focus on EBVALLO BLA resubmission and CAR-T wind-down.
- Paused ATA3219 and ATA3431 CAR-T programs; discontinued Phase 1 NHL study for ATA3219.
- FDA CRL in Jan 2025 cited third-party manufacturing issues; clinical hold on EBVALLO; regulatory update expected in Q2 2025.

## SEC filing metadata
- accession: 0000950170-25-035482
- form_type: 8-K
- ticker: ATRA
- cik: 0001604464
- company_name: Atara Biotherapeutics, Inc.
- filed_at: 2025-03-07T23:59:59+00:00
- event_type: earnings
- sentiment: negative
- materiality_score: 0.85
- calibrated_materiality_score: 0.85
- confidence: high
- sec_items: 2.02, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1604464/000095017025035482/0000950170-25-035482-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1604464/000095017025035482/atra-20250307.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0000950170-25-035482
- JSON: https://secwatch.observer/filing/0000950170-25-035482.json
- Plain text: https://secwatch.observer/filing/0000950170-25-035482.txt

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