Company: MBIO
Filing Date: 2025-04-01
Form Type: 424B3
Source: 0001104659-25-030657
Chunk: 19

Company: MUSTANG BIO, INC.
Filing Date: 2025-04-01
Form: 424B3
Chunk 19
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 infect other tumor cells in the vicinity and continue the process of tumor kill. In addition to this direct oncolytic
activity, the virus promotes an immune response against surviving tumor cells, which increases the antitumor effect of the therapy. The
virus expresses a gene from another virus from the same overall virus family, human cytomegalovirus, which allows it to replicate better
in the tumor cells than its first-generation predecessors. However, the virus has also been genetically engineered to minimize the production
of any toxic effects for the patient receiving the therapy.

To improve this virus over its first-generation
predecessors, modifications have focused on improving viral replication and spread within the tumor bed and on enhancing bystander damage
to uninfected tumor cells. These effects cumulatively should result in converting an immunologically cold tumor to an immunologically
hot tumor, which we anticipate will increase the efficacy of our IL13Rα2-directed CAR T for the treatment of GBM and high-grade astrocytoma.

The O’Neal Comprehensive Cancer Center at
the UAB is the single clinical trial site for the first Phase 1 trial of MB-108. This site initiated in 2019 (ClinicalTrials.gov Identifier:
NCT03657576) and, after enrolling 19 patients, has completed the treatment phase, and patients continue to be assessed for long-term safety.
The primary objective of this study is to determine the safety and tolerability of a single dose of MB-108 administered via a stereotactic
intracerebral injection and to determine the maximally tolerated dose (“MTD”) of the oncolytic virus. Secondary objectives
are to obtain preliminary information about the potential benefit of MB-108 in the treatment of patients with recurrent malignant gliomas,
including relevant data on markers of efficacy, including time to tumor progression and patient survival. Results from this trial were
used to determine the dose of MB-108 approved by the FDA for combination with MB-101 in the treatment of patients with IL13Rα2+ recurrent
GBM and high-grade astrocytoma under the originally proposed Mustang IND multicenter trial. We believe that the same doses of both therapies
will be appropriate for the Phase 1 investigator-sponsored single-institution combination trial currently under discussion with COH and
Nationwide.

Also listed on ClinicalTrials.gov are two additional
Phase 1 trials at UAB involving MB-108 administered as a single agent to patients with recurrent malignant glioma: (1)