---
schema_version: "secwatch.filing_event.v1"
accession: "0001860782-24-000048"
form_type: "8-K"
ticker: null
cik: "0001860782"
company_name: "2seventy bio, Inc."
filed_at: "2024-04-01T23:59:59+00:00"
generated_at: "2026-06-04T04:58:34.469247+00:00"
event_type: "m_and_a"
sentiment: "positive"
materiality_score: 0.8
calibrated_materiality_score: 0.8
confidence: "high"
source: SEC EDGAR
---

# 2seventy bio closes sale of oncology/autoimmune pipeline to Regeneron; focuses on Abecma

## Summary
- Sold oncology/autoimmune R&D programs and clinical manufacturing to Regeneron for $5M upfront; eligible for $10M milestone and royalties.
- Approximately 160 employees hired by Regeneron; 2seventy now ~65 employees, exclusively focused on Abecma commercialization with BMS.
- Pro forma net loss for 2023 adjusted from $217.6M to $135.5M; cash runway extended beyond 2027.
- Amended transition agreement with ex-CEO Nick Leschly clarifies eligibility for benefit plans as Chairman.

## SEC filing metadata
- accession: 0001860782-24-000048
- form_type: 8-K
- cik: 0001860782
- company_name: 2seventy bio, Inc.
- filed_at: 2024-04-01T23:59:59+00:00
- event_type: m_and_a
- sentiment: positive
- materiality_score: 0.8
- calibrated_materiality_score: 0.8
- confidence: high
- sec_items: 2.01, 5.02, 7.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1860782/000186078224000048/0001860782-24-000048-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1860782/000186078224000048/tvst-20240329.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001860782-24-000048
- JSON: https://secwatch.observer/filing/0001860782-24-000048.json
- Plain text: https://secwatch.observer/filing/0001860782-24-000048.txt

## Key facts
- M&A Transactions
  2seventy bio, Inc. completed a disposition involving Regeneron Pharmaceuticals, Inc. for $5 million in cash (closed 2024-04-01).
  - Action: disposition
  - Counterparty: Regeneron Pharmaceuticals, Inc.
  - Consideration: $5 million in cash
  - Closing: 2024-04-01
  source text: On April 1, 2024, the Company completed the transactions contemplated by the Asset Purchase Agreement (the “Asset Sale”) and Regeneron paid the Company $5 million in cash and assumed certain related liabilities.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1860782/000186078224000048/0001860782-24-000048-index.htm

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