Precision BioSciences to Highlight Capabilities of ARCUS Gene Editing for Allogeneic CAR T Cell Immunotherapies at The Society for Immunotherapy of Cancer 36th Annual Meeting

Precision BioSciences, Inc. (Nasdaq: DTIL), a clinical stage biotechnology company using its ARCUS® genome editing platform to develop allogeneic CAR T and in vivo gene editing therapies, today announced that the abstract titled, “Allogeneic CAR T cells with Deoxycytidine Kinase Knockdown Demonstrate Resistance to Fludarabine” has been accepted for poster presentation at the Society for Immunotherapy of Cancer (SITC) 36^th Annual Meeting taking place November 10 – 14, 2021 in Washington, D.C.

Abstract/Poster Details:

Abstract Number & Title: Abstract #140. Allogeneic CAR T cells with Deoxycytidine Kinase Knockdown Demonstrate Resistance to Fludarabine

Category: Cellular Therapies

Authors: Michelle B. Pires, M.S., and Aaron J. Martin, Ph.D., both of Precision BioSciences

Abstracts for the SITC 36^th Annual Meeting are now available on the SITC Annual Meeting website and in the Journal for ImmunoTherapy of Cancer (JITC). This abstract will be presented as an electronic poster that will be displayed on the SITC 2021 virtual meeting platform from 7 AM EST on Friday, November 12, 2021 until the virtual meeting platform is closed on January 9, 2022.

In this preclinical study, ARCUS gene editing was used to disrupt the endogenous T cell receptor by inserting a transgene carrying a CD19-specific CAR and an RNAi sequence designed to specifically knockdown deoxycytidine kinase (dCK), a protein that converts fludarabine from its prodrug form to an active compound. This single-step approach generated allogeneic, fludarabine-resistant (FluR) CAR T cells. In these cells, the dCK RNAi sequence produced a 70% reduction in dCK mRNA abundance, and resistance to fludarabine was confirmed in vitro. Additionally, treatment of tumor-bearing mice with fludarabine and FluR CAR T cells resulted in enhanced tumor clearance and survival compared to mice receiving control CAR T cells alone or control CAR T cells and fludarabine.

About Precision BioSciences, Inc.

Precision BioSciences, Inc. is a clinical stage biotechnology company dedicated to improving life (DTIL) with its novel and proprietary ARCUS® genome editing platform. ARCUS is a highly specific and versatile genome editing platform designed with therapeutic safety, delivery, and control in mind. Using ARCUS, the Company’s pipeline consists of multiple “off-the-shelf” CAR T immunotherapy clinical candidates and several in vivo gene editing candidates designed to cure genetic and infectious diseases where no adequate treatments exist. For more information about Precision BioSciences, please visit www.precisionbiosciences.com.

Forward-Looking Statements

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