Sangamo Therapeutics : Corporate Presentation

Pioneering and

Delivering the Future of

Genomic Medicines

November 2023

Forward-Looking Statements

This presentation contains forward-looking statements regarding our current expectations.These forward-looking statements include, without limitation, statements relating to our focus on epigenetic regulation and delivery engineering, the potential to develop, obtain regulatory approvals for and commercialize durable, safe and effective therapies to treat certain diseases and the timing, availability and costs of such therapies, the potential to use ZF, ZF-TR,CAR-Treg, SIFTER and other technologies to develop durable, safe and effective therapies, the potential for us to benefit and earn milestone and royalty payments from our collaborations and the timing of any such benefits and payments, our cell therapy strategy, including expansion to additional indications, plans and timing regarding our financial resources, including the sufficiency thereof and plans to reduce our operating expenses, the impact of our announced restructuring and Brisbane headquarter shutdown and future potential cost reductions, anticipated plans and timelines for us and our collaborators to enroll patients in and conduct clinical trials, dose and screen patients, present clinical data and make regulatory submissions, the anticipated advancement of our product candidates to late-stage development, including potential future Phase 3 trials, execution of our corporate strategy, our pipeline, the identification of additional targets, and the advancement of preclinical programs to the clinic, key milestones and catalysts, and other statements that are not historical fact.These statements are not guarantees of future performance and are subject to certain risks and uncertainties that are difficult to predict. Our actual results may differ materially and adversely from those expressed. Factors that could cause actual results to differ include, without limitation, risks and uncertainties related to the effects of the COVID-19 pandemic and the impacts of the pandemic and other macroeconomic factors, including as a result of ongoing overseas conflicts, disruptions in access to bank deposits and lending commitments due to bank failure, on the global business environment, healthcare systems and business and operations of us and our collaborators, including the initiation and operation of clinical trials; the research and development process; the uncertain timing and unpredictable results of clinical trials, including whether preliminary or initial clinical trial data will be representative of final clinical trial data and whether final clinical trial data will validate the safety, efficacy and durability of product candidates; the impacts of clinical trial delays, pauses and holds on clinical trial timelines and commercialization of product candidates; the unpredictable regulatory approval process for product candidates across multiple regulatory authorities; the manufacturing of products and product candidates; the commercialization of approved products; the potential for technological developments that obviate technologies used by us and our collaborators; the potential for us or our collaborators to breach or terminate collaboration agreements; the potential for us to fail to realize our expected benefits of our collaborations; the uncertainty of our future capital requirements, financial performance and results, our lack of capital resources to fully develop, obtain regulatory approval for and commercialize our product candidates, including our ability to secure the funding required to initiate a potential Phase 3 trial of ST-920 in a timely manner or at all; and our need for substantial additional funding to execute our operating plan and to operate as a going concern.There can be no assurance that we and our collaborators will be able to develop commercially viable products.These risks and uncertainties are described more fully in our Annual Report on Form 10-K for the fiscal year ended December 31, 2022, as supplemented by our Quarterly Report on Form 10-Q for the quarter ended September 30, 2023 to be filed with the Securities and Exchange Commission, or SEC, and future reports filed with the SEC. Forward-looking statements contained in this presentation speak only as of the date hereof, and we undertake no duty to update such information except as required under applicable law.This presentation concerns investigational product candidates that are under preclinical and/or clinical investigation and which have not yet been approved for marketing by any regulatory agency.They are currently limited to investigational use, and no representations are made as to their safety or efficacy for the purposes for which they are being investigated.Any discussions of safety or efficacy are only in reference to the specific results presented here and may not be indicative of an ultimate finding of safety or efficacy by regulatory agencies.

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We are a genomic medicine company dedicated to translating ground- breaking science into medicines that transform the lives of patients and families afflicted with serious neurological disease

Zinc finger

epigenetic regulation technology, with potent neurology programs advancing towards the clinic

Robust AAV capsid

discovery platform making strong progress expanding delivery beyond currently available intrathecal delivery capsids

Powerful research platform	Value-driving programs show
continually innovates in	technology proof of concept.
new modes of genome	Seeking ways to optimize
modulation to support value	value from Fabry disease
creation for both wholly	and CAR-Tregcell therapy
owned programs and	programs.
potential partners

S H A R P E N E D S T R AT E G I C F O C U S		O P T I M I Z E V A L U E

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Sangamo is advancing a next-generation neurology genomic medicine company by combining our expertise in epigenetic regulation and delivery engineering

Genome-Targeting Cargo

Epigenetic regulation platform

• Highly potent, specific and optimizable
• Easily packaged into AAVs
• Highly flexible - epigenetic gene repression, activation, and multiplexed approaches
• Led by Nav1.7 program in chronic neuropathic pain
  (≥ 43,000 patients in the US.)
• Prion disease program advancing a potential treatment for devastating and fatal disease

Capsid Delivery Engine

AAV capsid delivery platform

• SIFTER platform is advancing discovery of CNS-tropic AAV delivery capsids
• One-timeadministration with durable expression
• Engineered capsids for enhanced intrathecal delivery are already identified and being optimized
• Making strong progress identifying IV-delivered capsids to access previously untouched areas of the nervous system, which would open significant untapped indications

Neurology Genomic Medicines

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3Q23 Key Takeaways

Pipeline prioritization and sharpened strategic focus

Announced progression of strategic transformation to become a neurology-focus genomic medicine company. Focusing resources on proprietary epigenetic regulation programs and novel capsid delivery engine.

Announced planned shutdown of Brisbane headquarters, restructuring of operations, and US workforce reduction of approximately 40% to reduce operating expenses.

Financial Highlights

• Approximately $132 million in cash, cash equivalents, and marketable securities as of September 30, 2023 which, in combination with cost savings from the restructuring, workforce reduction and other potential cost reductions, we believe will be sufficient to fund planned operations into 3Q 2024.
• Restructuring activities and other potential cost reductions expected to reduce our non-GAAPoperating expenses from $240-260 million in 2023 to $115-135million for 2024, a decrease of approximately 50%.
• Continue to actively explore ways to raise additional capital.

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3Q23 Key Takeaways

Processes to unlock program value are underway

Fabry Disease

• Deferring additional investments in Phase 3 planning until collaboration partner or Phase 3 trial funding is secured.
• Expect to complete dosing of the remaining enrolled Phase 1/2 STAAR study patients in the first half of 2024.

CAR-Tregs

• Received necessary approvals for accelerated dosing protocol for Phase 1/2 STEADFAST study from European regulatory authorities.
• Deferring new investments in the CAR-Treg cell therapy programs until collaboration partner or external investment is secured.

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Prioritized Pipeline and Delivery Platform

Prioritized Neurology Pipeline

Indication	Technology	Preclinical	Phase 1/2	Pivotal
Chronic Neuropathic Pain (Nav1.7)	ZF Genome Engineering	Data presented at ASGCT 2023
Prion Disease	ZF Genome Engineering	Data presented at Prion 2023
Neurology (undisclosed)	ZF Genome Engineering

Partnered Programs

Indication	Technology
Hemophilia A (Giroctogene fitelparvovec)	Gene Therapy
Oncology	Cell Therapy
ALS/FTD	ZF Genome Engineering
Huntington's Disease	ZF Genome Engineering
Other Pipeline
Indication	Technology
Fabry Disease	Gene Therapy
Renal Transplant (TX200; Auto)	Treg Cell Therapy
Inflammatory Bowel Disease	Treg Cell Therapy
Multiple Sclerosis	Treg Cell Therapy

Preclinical	Phase 1/2	Pivotal

Preclinical	Phase 1/2	Pivotal

Anticipate presenting updated Phase 1/2 data in early 2024

Four patients dosed in Phase 1/2

Data presented at ESGCT 2023

Data presented at ESGCT 2023

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Recent

Business

Updates

CORPORATE UPDATES

• Announced progression of strategic transformation to become a neurology-focused genomic medicine company.
• Announced planned shutdown of Brisbane headquarters, restructuring of operations, and US workforce reduction of approximately 40% to reduce operating expenses.

NEUROLOGY EPIGENETIC REGULATION

• Progressed IND-enabling activities for Nav1.7 program for chronic neuropathic pain.
• Presented updated preclinical data fromprion disease programat the Prion 2023 Conference.
• Presented preclinical data showing zinc finger activators inSCN2Aand Shank3programs at ESGCT 2023.

FABRY DISEASE

• Dosed an additional three patients in Phase 1/2 STAAR study to achieve a total of 25 patients dosed.
• All patients dosed to date continue to demonstrate sustained, elevated α-Gal levels for up to 3 years-follow up.
• Received U.S. FDA Regenerative Medicine Advanced Therapy (RMAT) Designation.
• Deferring additional investments in Phase 3 planning until collaboration partner or Phase 3 trial funding is secured.

CAR TREG IMMUNE REGULATION

• Received necessary approvals for accelerated dose escalation protocol for Phase 1/2 STEADFAST study.
• Dosed first patient in second dose cohort. Manufactured dose for cohort three and four patients.
• Presented preclinical data onMOG-CAR-Tregsin multiple sclerosis, and IL23Rin Crohn's disease at ESGCT 2023.
• Deferring new investments in CAR-Treg programs until collaboration partner or external investment is secured.

HEMOPHILIA A (PFIZER)

• Dosing complete in Phase 3 AFFINE trial.
• Pivotal data read-out expected in mid-2024.
• BLA and MAA submissions anticipated in second half of 2024.

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Looking

Ahead:

Anticipated

Milestones

Neurology Epigenetic Regulation Programs

• IND submission for Nav1.7 expected in 2024.
• Anticipate sharing nonhuman primate data from our engineered AAV capsid development efforts in early 2024.

Fabry Disease

• Expect to complete dosing of the remaining enrolled Phase 1/2 STAAR study patients in the first half of 2024.
• Anticipate presenting updated Phase 1/2 data at a medical meeting in early 2024.
• Update on Phase 3 potential collaboration or financing options when appropriate.

CAR-Treg in Immune Regulation

• Expect to dose patient in third cohort in 4Q 2023.
• Expect to dose first patient in fourth cohort in January 2024.
• Plan to provide an update on discussions with potential investors in 1Q 2024.
• Plan to share Phase 1/2 clinical data by the middle of 2024.

Hemophilia A (Pfizer)

• Pivotal data readout estimated mid-2024.
• BLA and MAA submissions anticipated in 2H 2024.
• Eligible to receive up to $220m in potential milestones and 14-20% royalties.
• Updated Phase 1/2 ALTA data presentation at ASH, December 11, 2023.

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Our current financial resources are focused on pipeline progression and value creation

Key Financial Metrics		2023 Financial Guidance

	~$132m		$817m		$9.4m		$64.8m*
	Cash and Marketable		Cash Received from		Revenues - Q3 2023		Non-GAAP OpEx - Q3 2023
	Securities Balance as of 9/30/23		Partners to date
	Up to $1.9bn		Up to $220m		$240 - $260m
	In potential future milestones and		in potential milestone payments		Reiterated Non-GAAP OpEx Guidance excludes certain non-cash
	exercise fees, assuming exercise		from Hemophilia A† plus 14-20%
	of all options and targets		in potential sales royalties		charges as noted below**
	Our resources are tightly allocated in line with our business priorities

* Non-GAAP opex of $64.8 million excludes impairment of long-lived asset of $44.8 million, and stock-based compensation expense of $6.2 million.

** On a GAAP basis we expect our 2023 operating expenses to be in the range of $422 - $442 million, including non-cash charges consisting of impairment of goodwill of $38.1 million, impairment of indefinite-lived intangible assets of	10
$51.3 million, impairment of long-lived assets of $65.2 million, and stock-based compensation expense of $28 million.
† Currently in Phase 3 trial with Pfizer