Company: MBIO
Filing Date: 2025-04-01
Form Type: 424B3
Source: 0001104659-25-030657
Chunk: 13

Company: MUSTANG BIO, INC.
Filing Date: 2025-04-01
Form: 424B3
Chunk 13
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 patients with grade 1 and four
patients with grade 2. One patient experienced grade 1 ICANS. No grade 3 or 4 CRS or grade 2, 3 or 4 ICANS was observed, despite dose
escalation.

In May 2024, we informed the clinical sites participating
in the Mustang-sponsored Phase 1/2 study in non-Hodgkin lymphoma and chronic lymphocytic leukemia, MB106-CD20-001, that we had decided
to close the trial. In June 2024, we similarly informed the clinical sites participating in the Mustang-sponsored Long-term Follow-up
Study in Patients Previously Treated with Mustang Bio, Inc. CAR-T Cell Investigational Products, MB100-OBS-001, that we had decided to
close that trial. As a result, further clinical development of MB-106 is

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currently focused solely on autoimmune diseases
unless funding and resources become available to restart the program for hematologic malignancies. Planning for the aforementioned Phase
1 investigator-sponsored clinical trial in autoimmune diseases is in progress, with initiation of the trial planned for 2025.

To date, we have not received approval for the
sale of any of our product candidates in any market and, therefore, have not generated any product sales from our product candidates.
In addition, we have incurred substantial operating losses since our inception and expect to continue to incur significant operating losses
for the foreseeable future and may never become profitable. As of December 31, 2024, we had an accumulated deficit of $396.7
million.

We are a majority-controlled subsidiary of Fortress
Biotech, Inc. (“Fortress”).

CORPORATE INFORMATION

We were incorporated in Delaware on March 13,
2015. Our executive offices are located at 95 Sawyer Road, Suite 110, Waltham, Massachusetts 02453. Our telephone number is (781) 652-4500,
and our email address is .

Our website address is www.mustangbio.com. The
information set forth on our website is not a part of this Form 10-K. We will make available free of charge through our website our annual
reports on Form 10-K, quarterly reports on Form 10-Q and current reports on Form 8-K, and any amendments to these reports,
as soon as reasonably practicable after we electronically file such material with, or furnish such material to, the SEC. We