Company: MBIO
Filing Date: 2025-04-01
Form Type: 424B3
Source: 0001104659-25-030657
Chunk: 119

Company: MUSTANG BIO, INC.
Filing Date: 2025-04-01
Form: 424B3
Chunk 119
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109 (Combination of MB-101 CAR T Therapy with MB-108 Oncolytic Virus Therapy for Malignant Brain Tumors)

In October 2023, we received a safe-to-proceed
“approval” from the FDA for our MB-109 IND application allowing us to initiate a Phase 1, open-label, non-randomized, multicenter
study of MB-109 in patients with IL13Rα2+ recurrent GBM and high-grade astrocytoma. This Phase 1 clinical study was designed to evaluate
the combination of CAR-T cells (MB-101) and the herpes simplex virus type 1 oncolytic virus (MB-108) in patients with IL13Rα2+ high-grade
gliomas. As originally written and approved by the FDA, the study involved first a lead-in cohort, wherein patients would have been treated
with MB-101 alone without prior MB-108 administration. This lead-in cohort was required by the FDA due to the change in cell processing
site from COH to Mustang Bio, which would have involved methodological changes as well as the obvious change in equipment and personnel.
After successful confirmation of the safety profile of MB-101 alone, the study would have then investigated increasing doses of intratumorally
administered MB-108 followed by dual intratumoral (ICT) and intraventricular (ICV) administration of MB-101.

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On November 7, 2024, we announced that the FDA
granted Orphan Drug Designation to Mustang for MB-108, a herpes simplex virus type 1 (“HSV-1”) oncolytic virus, for the treatment
of malignant glioma. The Orphan Drug Designation provides certain incentives, such as tax credits toward the cost of clinical trials upon
approval and prescription drug user fee waivers. If a product receives Orphan Drug Status from the FDA, that product is entitled to seven
years of market exclusivity for the disease in which it has Orphan Drug designation, which is independent from intellectual property protection.

We are currently exploring with COH and Nationwide
the possibility of conducting an investigator-sponsored single-institution trial under the COH IND to treat patients with IL13Rα2+
recurrent GBM and high-grade astrocytoma with MB-109 that could potentially be initiated in the fourth quarter of 2025. Because cell processing
for MB-101 will revert back to CO