• ADI-270 includes Adicet’s proprietary armoring technology and enhancements designed for improved persistence and durability within a solid tumor microenvironment (TME)
• ADI-270 demonstrated potent anti-tumor activity in CD70+ cancers and improved resilience to clearance from host immune targeting

REDWOOD CITY, Calif. & BOSTON / May 18, 2023 / Business Wire / Adicet Bio, Inc. (Nasdaq: ACET), a clinical stage biotechnology company discovering and developing allogeneic gamma delta T cell therapies for cancer, today announced preclinical data highlighting ADI-270, an armored allogeneic “off-the-shelf” gamma delta CAR (chimeric antigen receptor) T cell therapy candidate targeting CD70+ cancers, at the 26th Annual Meeting of the American Society of Gene & Cell Therapy (ASGCT) taking place from May 16-20, 2023, in Los Angeles, CA.

“We believe that ADI-270, combined with a third generation CAR and armoring technologies designed to improve persistence and resilience within the TME, may be able to overcome multiple barriers for realizing efficacy for cell therapies in solid tumors. Together with both innate and adaptive immune targeting and tumor infiltration, we believe ADI-270 can potentially improve clinical outcomes for patients,” said Dr. Blake Aftab, Ph.D., Chief Scientific Officer of Adicet. “These findings provide critical groundwork to support the continued clinical development of ADI-270 as a potentially meaningful therapeutic option.”

In this study, gamma delta T cells modified to express CD70 CAR were successfully generated and expanded without evident hindrances from CD70-mediated fratricide in the process. Data being presented included the following findings:

• ADI-270 demonstrated preclinical proof-of-concept as an armored allogeneic gamma delta CAR T cell therapy candidate utilizing the CD27 natural receptor in a third generation CAR format for targeting CD70-positive cancers.
• ADI-270 gamma delta 1 CAR T cells expressed a predominant naïve-like memory phenotype with potent in vitro cytotoxicity and production of proinflammatory cytokines against CD70+ tumor cell lines via multiple mechanisms.
• ADI-270 showed significant inhibition of tumor growth in CD70+ tumor cell lines, which was maintained in the presence of TGF beta inhibitory factor, and exhibited improved resistance to killing by host T cell rejection.
• ADI-270 also demonstrated marked biodistribution and infiltration into solid tumor models of renal cell carcinoma.

Details for the poster presentations are as follows:

Title: ADI-270: An Armored Allogeneic “Off-the-Shelf” CAR gamma delta T Cell therapy Targeting CD70+ Cancers

Abstract Number: 1023
Poster Session: Thursday Poster Session
Date & Time: May 18, 2023 at noon

About Adicet Bio, Inc.

Adicet Bio, Inc. is a clinical stage biotechnology company discovering and developing allogeneic gamma delta T cell therapies for cancer. Adicet is advancing a pipeline of “off-the-shelf” gamma delta T cells, engineered with chimeric antigen receptors (CARs) and chimeric antigen adaptors (CAds), to enhance selective tumor targeting and facilitate innate and adaptive anti-tumor immune response for durable activity in patients. For more information, please visit our website at https://www.adicetbio.com.

Forward-Looking Statements

This press release contains "forward-looking statements" of Adicet within the meaning of the Private Securities Litigation Reform Act of 1995 relating to the business and operations of Adicet. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “would” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. These forward-looking statements include, but are not limited to, express or implied statements regarding: preclinical and clinical development of Adicet’s product candidates, including future plans or expectations for ADI-270.

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