SANGAMO THERAPEUTICS REPORTS FIRST QUARTER 2019 FINANCIAL RESULTS Conference Call and Webcast Scheduled for 5:00 p.m. Eastern Time Brisbane, California

SANGAMO THERAPEUTICS REPORTS FIRST QUARTER 2019 FINANCIAL RESULTS

Conference Call and Webcast Scheduled for 5:00 p.m. Eastern Time

Brisbane, California, May 8, 2019 Sangamo Therapeutics, Inc. (NASDAQ: SGMO), a genomic medicine company, today

reported first quarter 2019 financial results and recent business highlights.

With recent encouraging clinical data in hemophilia A gene therapy

and ex vivo gene-edited cell therapy for beta thalassemia, we are moving closer to achieving our vision for Sangamo as an integrated genomic medicine company, said Sandy Macrae, CEO of Sangamo. Our capabilities in gene therapy,

ex vivo gene-edited cell therapy, in vivo genome editing and gene regulation enable us to address genetic diseases with appropriate technologies. We are investing in a diverse pipeline of products where we believe this suite of

proprietary technologies is clinically relevant, where the underlying biology is well-characterized, and where there is a defined high unmet medical need.

First Quarter 2019 Financial Results

quarter ended March 31, 2019, Sangamo reported a consolidated net loss of $42.2 million, or $0.41 per share, compared to a net loss of $20.2 million, or $0.23 per share, for the same period in 2018. As of March 31, 2019, the

Company had cash, cash equivalents, and investments of $351.6 million.

Revenues for the first quarter ended March 31, 2019 were

$8.1 million, compared to $12.6 million for the same period in 2018. The decrease was primarily due to a decline of $10.6 million in revenues related to our agreement with Pfizer due to a change in estimate driven by an increase

in project scope of the hemophilia A collaboration and the corresponding decrease in the measure of the proportional performance, and also a $2.4 million decrease in revenues related to our agreement with Sanofi (formerly Bioverativ). These

decreases were partially offset by an increase of $8.3 million in revenue related to our agreement with Kite Pharma, which took effect in April 2018. First quarter 2019 revenues were primarily generated from Sangamo s collaboration

agreements with Kite, Sanofi and Pfizer.

As anticipated, operating expenses increased in the first quarter ended March 31, 2019, reflecting the

Company s growth through the acquisition of TxCell, increased U.S. headcount in support of growth of the preclinical pipeline and clinical development programs, and manufacturing-related activities. Total operating expenses for the first

quarter ended March 31, 2019 were $52.0 million, compared to $33.6 million for the same period in 2018. Research and development expenses were $34.9 million for the first quarter of 2019, compared to $23.5 million for the

same period in 2018. The increase was primarily due to manufacturing and clinical trial expenses related to the progress of the Company s clinical development programs. General and administrative expenses were $17.1 million for the first

quarter of 2019, compared to $10.1 million for the same period in 2018.

Financial Guidance for 2019

Sangamo will host a conference call today, May 8, 2019, at 5:00 p.m. Eastern Time, which will be open to the public. The call will also be

webcast live and can be accessed via a link on the Sangamo Therapeutics website in the Investors and Media section under Events and Presentations.

The conference call dial-in numbers are (877) 377-7553 for domestic callers

and (678) 894-3968 for international callers. The conference ID number for the call is 7577586. For those unable to listen in at the designated time, a conference call replay will be available for one week

following the conference call, from approximately 8:00 p.m. ET on May 8, 2019 to 11:59 p.m. ET on May 15, 2019. The conference call replay numbers for domestic and international callers are (855)

859-2056 and (404) 537-3406, respectively. The conference ID number for the replay is 7577586.

About Sangamo Therapeutics

Sangamo Therapeutics, Inc. is focused on translating ground-breaking science into genomic medicines with the potential to transform patients lives

using gene therapy, ex vivo gene-edited cell therapy, in vivo genome editing, and gene regulation. For more information about Sangamo, visit www.sangamo.com.

Forward-Looking Statements

contains forward-looking statements regarding Sangamo s current expectations. These forward-looking statements include, without limitation, statements regarding the Company s vision to become an integrated genomic medicines company, the

Company s ability to develop and commercialize product candidates to address genetic diseases with the Company s proprietary technologies, the anticipated benefit from investing in a diverse pipeline of products, and Sangamo s 2019

financial guidance related to cash, cash equivalents, and investments, anticipated operating expenses and cash runway. These statements are not guarantees of future performance and are subject to certain risks, uncertainties and assumptions that are

difficult to predict. Factors that could cause actual results to differ include, but are not limited to, the dependence on the success of clinical trials, the lengthy and uncertain regulatory approval process, uncertainties related to the

initiation, enrollment and completion of clinical trials, whether the final results from a study will validate and support interim safety and efficacy data, Sangamo s reliance on partners and other third-parties to meet their clinical and

manufacturing obligations, and the ability to maintain strategic partnerships. Further, there can be no assurance that the necessary regulatory approvals will be obtained or that Sangamo and its partners will be able to develop commercially viable

product candidates. Actual results may differ from those projected in forward-looking statements due to risks and uncertainties that exist in Sangamo s operations and business environments. These risks and uncertainties are described more fully

in Sangamo s Annual Report on Form 10-K for the year ended December 31, 2018 as filed with the Securities and Exchange Commission and Sangamo s Quarterly Report on Form 10-Q for the quarter ended March 31, 2019 that it intends to file this week. Forward-looking statements contained in this announcement are made as of this date, and Sangamo undertakes no duty to update such

information except as required under applicable law.

Investor Relations United States

Media Inquiries United

Investor Relations and Media Inquiries European Union

SELECTED CONSOLIDATED FINANCIAL DATA

(unaudited; in thousands, except per share data)

SELECTED BALANCE SHEET DATA