Company: MBIO
Filing Date: 2025-04-01
Form Type: 424B3
Source: 0001104659-25-030657
Chunk: 39

Company: MUSTANG BIO, INC.
Filing Date: 2025-04-01
Form: 424B3
Chunk 39
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 final marketing approval depends on the results of efficacy, the adverse event profile and
an evaluation of the benefit/risk of treatment demonstrated in the pivotal clinical trial. Once approved, the SPA may only be changed
through a written agreement between the sponsor and the FDA, or in rare cases if the FDA becomes aware of a substantial scientific issue
essential to product safety or efficacy the SPA can be rescinded.

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Table of Contents

The FDA has established the Office of Tissues
and Advanced Therapies, formerly called the Office of Therapeutic Proteins, which is a super office within the Center for Biologics Evaluation
and Research, or CBER, to consolidate the review of cell and gene therapies and related products. and has established the Cellular, Tissue
and Gene Therapies Advisory Committee to advise CBER in its review, if requested by FDA. The FDA is not bound by the recommendations of
an Advisory Committee, but it considers them carefully when making decisions. There are a number of additional requirements that apply
exclusively to clinical trials involving this class of products. The FDA has issued various guidance documents regarding gene therapies,
which outline additional factors that the FDA will consider at each of the above stages of development. These guidelines relate to, among
other things: preclinical evaluation of gene therapies, design of clinical studies, and the chemistry, manufacturing and control information
that should be included in an initial IND application and throughout clinical development to support an NDA or BLA application. Measures
to observe for delayed adverse effects in subjects who have been exposed to investigational gene therapies are required. Per the guidelines,
FDA requires that sponsors observe subjects for potential gene therapy-related delayed adverse events which can be, dependent upon various
factors, up to a period of 15 years post treatment.

FDA Review and Approval

Before receiving FDA approval to market a product,
we must demonstrate that the product is safe and effective for its intended use by submitting to the FDA an NDA or BLA containing the
preclinical and clinical data that have been accumulated, together with chemistry and manufacturing and controls specifications and information,
and proposed labeling, among other things. The FDA may refuse to accept an NDA or BLA for filing if certain content criteria are not met
and, even after accepting an NDA or BLA, the FDA may require additional information, including clinical data, before approval for marketing
a product.

Although uncommon, the FDA may request a Risk
Evaluation and Mitigation