Magenta Therapeutics : J.P. Morgan 2022 Presentation

J.P. Morgan Healthcare Conference (January 2022)

(NASDAQ:MGTA)

Forward-Looking Statements

This presentation may contain forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995 and other federal securities laws, including express or implied statements regarding Magenta's future expectations, plans and prospects, including, without limitation, statements regarding expectations and plans for presenting pre-clinical and clinical data, projections regarding our long-term growth, cash, cash equivalents and marketable securities, the anticipated timing of our clinical trials and regulatory filings, the development of our product candidates and

advancement of our pre-clinical and clinical programs, the timing, progress and success of our collaborations, as well as other statements containing words such as "may," "will," "could", "should," "expects," "intends," "plans," "anticipates," "believes," "estimates," "predicts," "projects," "seeks," "endeavor," "potential," "engineered," "designed," "vision," "continue" or the negative of such words or other similar expressions that can be used to identify forward- looking statements.

The express or implied forward-looking statements included in this presentation are only predictions and are subject to a number of risks, uncertainties and assumptions, including, without limitation: uncertainties inherent in clinical studies and in the availability and timing of data from ongoing clinical studies; whether interim results from a clinical trial will be predictive of the final results of the trial; whether results from pre-clinical studies or earlier clinical studies will be predictive of the results of future trials; the expected timing of submissions for regulatory approval or review by governmental authorities, including review under accelerated approval processes; orphan drug designation eligibility; regulatory approvals to conduct trials or to market products; whether Magenta's cash resources will be sufficient to fund Magenta's foreseeable and unforeseeable operating expenses and capital expenditure requirements; risks, assumptions and uncertainties regarding the impact of the continuing COVID-19 pandemic on Magenta's business, operations,

strategy, goals and anticipated timelines, Magenta's ongoing and planned pre-clinical activities, Magenta's ability to initiate, enroll, conduct or complete ongoing and planned clinical trials, Magenta's timelines for regulatory submissions and Magenta's financial position; and other risks concerning Magenta's programs and operations set forth under the caption "Risk Factors" in Magenta's Annual Report on Form 10-K filed on March 3, 2020, as updated by Magenta's most recent Quarterly Report on Form 10-Q and its other filings made with the Securities and Exchange Commission from time to time.

In light of these risks, uncertainties and assumptions, the forward-looking statements discussed in this presentation may not occur and actual results could differ materially and adversely from those anticipated or implied in the forward-looking statements. You should not rely upon forward-looking statements as predictions of future events. Although Magenta believes that the expectations reflected in the forward-looking statements are reasonable, it cannot guarantee that the future results, levels of activity, performance or events and circumstances reflected in the forward-looking statements will be achieved or occur. Any forward-looking statement included in this presentation speaks only as of the date on which it was made. Magenta undertakes no obligation to publicly update or revise any forward-looking statement, whether as a result of new information, future events or otherwise, except as required by law.

2 (NASDAQ:MGTA)

Stem Cell Transplant is a Platform for Advancing Cell and Gene Therapies

	Autologous
	Stem Cell
	Gene Therapy
Stem Cell	SCD, Lysosomal
Storage Disorders
Transplant
for Oncology
Heme Oncology

TODAY

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	Emerging Cell and
	Gene Therapies
Stem Cell	In Vivo Gene
Therapy, Allogeneic
Transplant for
Cell Therapies
Autoimmune
Disease

MS, Systemic

Sclerosis

Large Existing Markets with Significant Remaining Unmet Medical Needs

High unmet need to expand eligibility for stem cell transplants and gene therapies

	HSC Gene Therapy	Autoimmune Diseases1
Heme-Oncology	in Sickle Cell Disease	~85k Incident patients / Year
135,000 Incident patients / Year	150,000 Prevalent patients	~1.5M Prevalent patients

100%

68%

Incidence

80%

>99%

Prevalent

Prevalent

10%

22%

20%

<1% receive HSCT today

~10% Incident

0%

Currently transplanted

Current eligible pop

Current eligible pop

Additionally eligible for transplant

Initial eligible for GT

Initial eligible for transplant

Incidence

Future eligible pop with

Future eligible pop with

improved conditioning

improved conditioning

4 Sources: Decision Resources Epidemiology, Magenta Market Research 2020, Transplant Volumes as reported by CIBMTR, EBMT, and APBMT 1 Multiple Sclerosis and Systemic Sclerosis

The Magenta Pipeline

Disease Area

Preclinical

IND-Enabling

Phase 1

Phase 2

Clinical Trial

Product Rights

Partners

Multiple Myeloma

Autologous Transplant

MGTA-145

Leukemias

Allogeneic Transplant

Stem Cell Mobilization

and Collection:

Sickle Cell Disease

Gene Therapy

Leukemias

AML/MDS

MGTA-117

Lysosomal Disorders

Gene Therapy

Targeted Conditioning:

Hemoglobinopathies

Gene Therapy

CD45-ADC

Heme-Oncology

CD$5

Targeted Conditioning:

Autoimmune Disease

Research Platform

Novel Target Conditioning

& Translational Stem Cell

Science

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