Mustang Bio : Corporate Presentation

Corporate Presentation

March 2024

Cautionary Statement

This presentation contains "forward-looking statements" within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. For such forward-looking statements, we claim the protection of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995. Such statements include, but are not limited to, any statements relating to our growth strategy, products and product development programs , including the timing of and our ability to make regulatory filings such as INDs and other applications and to obtain regulatory approvals for our product candidates, statements concerning the potential of therapies and product candidates, statements regarding the potential addressable market of our therapies and any other statements that are not descriptions of fact. Forward-looking statements are based on management's current expectations and are subject to risks and uncertainties that could negatively affect our business, operating results, financial condition and stock price. Factors that could cause actual results to differ materially from those currently anticipated include , among other things, risks related to whether the Company's third-party manufacturer is able to successfully perform its obligation to produce the Company's products under the manufacturing services agreement on a timely basis and to acceptable standards, disruption from the sale of the Company's manufacturing facility making it more difficult to maintain business and operational relationships, negative effects of the announcement of the consummation of the sale of the Company's manufacturing facility on the market price of the Company's common stock, significant transaction costs, the development stage of the Company's primary product candidates, our ability to obtain, perform under, and maintain financing and strategic agreements and relationships, risks relating to the results of research and development activities, risks relating to the timing of starting and completing clinical trials, uncertainties relating to preclinical and clinical testing; our dependence on third-party suppliers, our ability to attract, integrate and retain key personnel, the early stage of products under development, our need for substantial additional funds, government regulation, patent and intellectual property matters, competition, as well as other risks described in Part I, Item 1A, "Risk Factors," in our Annual Report on Form 10-K filed on March 30, 2023, subsequent Reports on Form 10-Q, and our other filings we make with the SEC. We expressly disclaim any obligation or undertaking to release publicly any updates or revisions to any forward-looking statements contained herein to reflect any change in our expectations or any changes in events, conditions or circumstances on which any such statement is based, except as may be required by law. The information contained herein is intended to be reviewed in its totality, and any stipulations, conditions or provisos that apply to a given piece of information in one part of this presentation should be read as applying mutatis mutandis to every other instance of such information appearing herein, as required by law.

This presentation also contains estimates and other statistical data made by independent parties and by us relating to market size and other data about our industry. These data involve a number of assumptions and limitations, and you are cautioned not to give undue weight to such data and estimates. In addition, projections, assumptions and estimates of our future performance and the future performance of the markets in which we operate are necessarily subject to a high degree of uncertainty and risk. Neither we nor our affiliates, advisors or representatives makes any representation as to the accuracy or completeness of that data or undertake to update such data after the date of this presentation.

Certain information contained in this presentation relates to or is based on studies, publications, surveys and other data obtained by third-party sources and the Company's own internal estimates and research. While the Company believes these third-party sources to be reliable as of the date of this presentation, it has not independently verified and makes not representation as to the adequacy, fairness, accuracy or completeness of, any information obtained from third- party sources.

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Mustang Bio is Pioneering Innovative CAR-T Therapies for Cancer and Gene Therapies for Primary Immunodeficiencies

Milestones

over next 12

months

• Expect additional disclosure of data from MB-106 indolent lymphoma Arm of Mustang-sponsored trial, with start of first pivotal trial in Waldenstrom macroglobulinemia mid-2024
• Expect to treat 1st pt on groundbreaking combination Ph 1 trial of CAR-T + oncolytic virus in malignant brain tumors
• Expect to publish proof-of-concept data in a murine cancer model for in vivo CAR-T program

Key Programs

	▪ First-in-classCD20-targetedCAR-T for non-Hodgkin lymphoma & chronic lymphocytic leukemia
MB-106	- First multicenter Mustang data presented at ASH in December 2023 provide early confirmation of Phase 1 Fred
Hutch trial across multiple institutions & multiple indolent histologies
	- Expect to treat 1st pt in pivotal Ph 2 trial for Waldenstrom macroglobulinemia mid-2024;top-line data mid-2026
MB-101 +	▪ First-in-class combination of CAR-T therapy + an oncolytic virus for malignant brain tumors
MB-108	▪ FDA granted safe-to-proceed for phase 1 trial October 2023; expect to treat first patient in 2024
In vivo	▪ Novel platform to make CAR-Ts in the patient's own body - i.e., not in a manufacturing facility
CAR-T	▪ Expect to publish first proof-of-concept data in 2024
MB-117 /	▪ Transformational gene therapies for XSCID* (rare genetic disease)
MB-217	▪ Phase 1 investigator IND trials with modified lentiviral vector expected to start in 2024

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* XSCID = X-linked severe combined immunodeficiency

Robust Pipeline of Therapies Addressing Highly Challenging Diseases

Therapeutic	Product (Target)		Pre-IND	Phase 1	Registrational
Modality		Phase 2
Hematologic CAR-T	MB-106 for NHL (including WM) & CLL (CD20)	Expect to start pivotal Waldenstrom
macroglobulinemia (WM) trial in 2024
Combination CAR-T	MB-101CAR-T for GBM		COH first-in-human (FIH) MB-101 Phase 1 complete
(IL13Rα2)	Combination	Expect to treat first
+
	= MB-109	patient in 2024
oncolytic virus (OV)
MB-108 OV for GBM
		UAB FIH MB-108 Phase 1 ongoing*
In vivo CAR-Ts	TBD		Publication expected
	2024
Ex-vivoGene	MB-117 (modified vector) for newborn XSCID
(IL2RG)		Investigator IND trials
Therapy
MB-217 (modified vector) for previously	expected to start 2024
	transplanted XSCID (IL2RG)

	CLL = Chronic lymphocytic leukemia	OV = Oncolytic virus
	COH = City of Hope National Medical Center	UAB = University of Alabama at Birmingham
	FIH = First-in-human	WM = Waldenstrom macroglobulinemia
	GBM = Glioblastoma	XSCID = X-linked severe combined immunodeficiency
	NIH = National Institutes of Health	* Partially or totally supported by grants`
4	NHL = Non-Hodgkin lymphoma

Leadership Team with Extensive Cell, Gene & Rare Disease Therapy Experience

Lynn E. Bayless, MS

VP & Head,

Regulatory Affairs

Greg Furrow, MS,

FRQA

Chief Quality Officer

Kerry Biron, BBA

VP & Head,

Clinical Operations

Manuel Litchman, MD

President & Chief Executive Officer

Richard Bodmer, MS	Bruce Dezube, MD
Head of CMC	Chief Medical Officer
Development

Debra Manning, SPHR	James Murphy, BA
Senior VP & Head,	Ad interim Chief
Human Resources	Financial Officer

James Edinger, PhD

Chief Scientific

Officer

Robert Sexton, MS,

MBA

VP & Head, Program &

Alliance Leadership

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R&D Collaborators: World Class Team of Scientific Experts

• Technology licensed from City of Hope (COH), Fred Hutch Cancer Center (FHCC), Nationwide Children's Hospital, St. Jude Children's Research Hospital, & Mayo Clinic
• Research based on pioneering work by:

Dr. Stephen Forman	Dr. Christine Brown	Dr. Brian Till	Dr. Kevin Cassady	Dr. Brian Sorrentino	Dr. Larry Pease
City of Hope	City of Hope	FHCC	Nationwide	St. Jude (1958-2018)	Mayo Clinic

MB-101

MB-106

MB-108

MB-117,MB-217

In vivo CAR-Ts

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We Engineer Patients' Cells with Goal of Long-Term Benefit

Editing T cells harnesses the immune system for precise targeting of the patient's tumor

Editing blood stem cells restores the patient's immune system crippled by genetic defect

1. Infuse cells back into patient

5. Cyclophosphamide & fludarabine

1. Cryopreservation

CAR-T therapy

(MB-101,MB-106)

1. Leukapheresis & T cell enrichment

2. Engineer T cells to express CAR

1. Bone marrow harvest or leukapheresis

Gene therapy

(MB-117,MB-217,MB-110*)

	Stem	Stem
Stem	cell Stem	cell
cell
cell
	Stem
	Stem	cell
	cell
	2. Engineer stem cells to
		express normal gene

3. Expand the modified T cells

3. Cryopreservation

5. Infuse cells back into patient

7 Source: Duan Q, et al. Trends in Cancer. 2020;6:605-618

4. Low-dose busulfan

*MB-110 = RAG1-SCID gene therapy in-licensed from Leiden Univ. Medical Centre

Asset Purchase Agreement Closed July 28, 2023, with uBriGene - US Division of Highly Experienced Chinese CDMO*; Cell Processing Has Continued Seamlessly

	▪	27,000 square foot potential commercial launch site
		currently owned by Mustang - will retain Mustang
Cleanroom space		personnel & support our clinical trials
	▪	Comprehensive cell processing capabilities, including
		sterility testing of final product

Office	Labs	▪ Lentiviral vectors to carry genetic payload are
(Quality Control, Process Devt,		produced at academic partners & CDMOs
	Analytical Devt & Research)	▪	Successful manufacturing of MB-106 product for all
			pts enrolled to date on Mustang-sponsored trial

Mustang has developed a universal platform process for autologous CAR-Ts

Day -1	Day 0 Day 2 Day 3	Day 7	Day 15+ Day 19+
			8-day sterility

Leukapheresis

Enrichment

Transduction

Expansion

Fill

Shipment

Infusion

CoA

Shipment

Activation

Wash

Harvest

Cryopreservation

Thawing

8	* Details of this Agreement may be found in our SEC filings

MB-106 Overview

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MB-106:CAR-T for Non-Hodgkin Lymphoma (NHL) & Chronic Lymphocytic Leukemia (CLL)

MB-106

MB-106

First-in-classCD20-targetedCAR-T cell therapy for treatment of relapsed/refractory NHL & CLL

• Competitive safety & efficacy profile vis-à-vis approved & investigational cell therapies & bispecific antibodies
• Clear regulatory pathway for autologous CAR-Ts based on FDA approval to date of 6 autologous CAR-Ts
• Currently enrolling multicenter Phase 1 Mustang- sponsored trial
• BLA strategy is to pursue indications where there are no approved CAR-Ts:
• 1. Waldenstrom macroglobulinemia (WM)
  2. DLBCL relapsed from CD19 CAR-Ts
  3. CLL

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Clinical development: 2 trials in progress

1. Ongoing Fred Hutch IND study: Plan to continue enrollment; expect publication of follicular lymphoma data in 2024
2. Mustang IND 6-center Phase 1/2 trial: Currently enrolling*
3. • 3-armstudy targeting relapsed/refractory disease
   • • Aggressive NHL
     • Indolent NHL
     • CLL
   • Relapses from CD19 CAR-Ts eligible in all arms
   • Indolent NHL arm includes Waldenstrom (fast-to-marketstrategy)
   • Since Mustang IND trial is using same lentiviral vector as Fred Hutch trial, FDA has allowed dose escalation to start higher than initial FHCC dose
   • Additional data disclosures from indolent NHL arm expected in 2024; expect to start pivotal WM Ph 2 trial mid-2024

• https://clinicaltrials.gov/ct2/show/NCT05360238