---
schema_version: "secwatch.filing_event.v1"
accession: "0001104659-25-066520"
form_type: "8-K"
ticker: "MBIO"
cik: "0001680048"
company_name: "MUSTANG BIO, INC."
filed_at: "2025-07-09T23:59:59+00:00"
generated_at: "2026-05-18T08:53:59.113257+00:00"
event_type: "regulatory"
sentiment: "positive"
materiality_score: 0.65
calibrated_materiality_score: 0.65
confidence: "high"
source: SEC EDGAR
---

# Mustang Bio gets FDA Orphan Drug Designation for MB-101 CAR T-cell therapy in astrocytomas and glioblastoma

## Summary
- FDA granted Orphan Drug Designation to MB-101 for recurrent diffuse/anaplastic astrocytoma and glioblastoma.
- Designation provides tax credits, fee waivers, and potential 7-year market exclusivity upon approval.
- Phase 1 trial showed 50% stable disease or better; two complete responses lasting 7.5 and 66+ months.
- Preclinical data support combining MB-101 with oncolytic virus MB-108 to improve efficacy.
- Company notes development of MB-109 program is contingent on raising additional funding.

## SEC filing metadata
- accession: 0001104659-25-066520
- form_type: 8-K
- ticker: MBIO
- cik: 0001680048
- company_name: MUSTANG BIO, INC.
- filed_at: 2025-07-09T23:59:59+00:00
- event_type: regulatory
- sentiment: positive
- materiality_score: 0.65
- calibrated_materiality_score: 0.65
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1680048/000110465925066520/0001104659-25-066520-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1680048/000110465925066520/tm2520081d1_8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001104659-25-066520
- JSON: https://secwatch.observer/filing/0001104659-25-066520.json
- Plain text: https://secwatch.observer/filing/0001104659-25-066520.txt

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