Sangamo Therapeutics : Corporate Presentation

Pioneering and

Delivering the Future of

Genomic Medicines

August 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 key strategic priorities, 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, 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 the ongoing conflict between Russia and Ukraine, 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; and the uncertainty of our future capital requirements, financial performance and results.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 June 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 medicines company dedicated to translating ground-breaking science into medicines that transform the lives of patients and families afflicted with serious disease

First wave of value-driving

programs advancing to/through late-stage development

Second wave of potentially transformative neurology and autoimmune programs advancing into the clinic

Powerful research platform

continually innovates to support value creation, including in delivery

Demonstrated track record of partnerships results in non dilutive funding, expands the portfolio, and offsets cost

2 0 2 3 V A L U E T H E S I S

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2Q23

Key Takeaways

Clinical Momentum Continues

Strong clinical momentum continues in Phase 1/2 STAAR study in Fabry disease with 22 patients dosed in total. Received Fast Track Designation from the FDA. Received productive written FDA feedback on proposed Phase 3 trial strategy. Expect to submit a Phase 3 protocol to the FDA as early as YE2023.

Safety Monitoring Committee endorsed advancing to cohort two of

Phase 1/2 CAR-Treg STEADFAST study for TX200 in HLA A2

mismatched kidney transplantation. Completed manufacturing of dose for first patient in second cohort, and dosing expected in 3Q23. Protocol amendment to accelerate dose escalation has been submitted to regulatory authorities, with first full country approval received.

Presented first preclinical data from Nav1.7 program for chronic neuropathic pain, demonstrating potent and specific repression of Nav1.7 expression. IND submission is expected in 2024.

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2Q23

Key Takeaways

Announced three strategic partnerships which create additional value, validate our own technology, and help advance our pipeline.

Business development to drive value

Evaluation and option agreement with Prevail Therapeutics granting rights to evaluate

Sangamo's novel

engineered CSF- administered AAV capsids with enhanced nervous system delivery.

Evaluation and option agreement with Chroma Medicine granting rights to evaluate Sangamo's zinc

finger proteins for

epigenetic editing in targets outside of the central nervous system (CNS).

License agreement with

Voyager Therapeutics

for access to Voyager's IV-

administered AAV

capsid with specific CNS coverage required for our

prion disease program.

Financial Highlights

• Approximately $182 million in cash, cash equivalents, and marketable securities as of June 30, 2023 which, in combination with other potential cost reductions, we believe will be sufficient to fund planned operations for at least the next 12 months.
• Reiterated expected 2023 non-GAAP operating expense range of $240-260 million for 2023.
• Continue to assess ways to raise additional capital and further focus our annual operating expenses consistent with the prioritized objectives and progress of the company.

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