Shattuck Labs Presents Updated Preclinical Data on Gamma Delta T Cell Engager (GADLEN) Platform Candidates at the Society for Immunotherapy of Cancer (SITC) Annual Meeting

- Data from two distinct GADLEN product candidates, one targeting CD20 and another targeting B7-H3, enhanced γδT cell killing of tumor cells, demonstrating preclinical proof-of-concept in the treatment of cancer -

AUSTIN, TX and DURHAM, NC, Nov. 07, 2022 (GLOBE NEWSWIRE) -- Shattuck Labs, Inc. (Shattuck) (NASDAQ: STTK), a clinical-stage biotechnology company pioneering the development of bi-functional fusion proteins as a new class of biologic medicine for the treatment of patients with cancer and autoimmune disease, today announced preclinical data from the company’s novel GADLEN platform at the 2022 SITC Annual Meeting.

“The data presented from these two compounds demonstrate the broad utility of the GADLEN platform to direct gamma delta T cells to kill target cells expressing an antigen (or antigens) of our choosing,” said Taylor Schreiber, M.D., Ph.D., Chief Executive Officer of Shattuck. “B7-H3 is an antigen that is broadly expressed by many solid tumors, with limited expression in normal tissues. In our preclinical models, our B7-H3 GADLEN directed human gamma delta T cells to selectively kill B7-H3 expressing human tumor cells, including those that expressed very low density of the B7-H3 antigen. Similarly, in our preclinical models, our CD20 GADLEN directed human gamma delta T cells to selectively kill both CD20 expressing tumor cells, and also CD20 expressing healthy B cells. The latter activity with the CD20 GADLEN may have distinct value in antibody-mediated autoimmunity, where non-Ig, non-CD3 based cell depletion strategies could have a unique therapeutic window.”

Details of the presentation are as follows:

Abstract title: Antigen targeted butyrophilin heterodimer-based bispecific engagers induce T cell-mediated anti-tumor activity

Shattuck presented preclinical data highlighting the potential of GADLENs to direct Vγ9δ2+ T cells to kill tumor cells. The bispecific GADLENs, which contain heterodimeric BTN2A1 and BTN3A1 extracellular domains fused via inert Fc linkers to scFv domains, targeting CD20 or B7-H3 antigens, demonstrated cytotoxic ability in coculture with Vγ9δ2+ T cells. CD20-directed GADLENs enhanced the specific killing of lymphoma cells and healthy B cells that express the antigen, while B7H3-directed GADLEN increased the killing of B7-H3 expressing tumor cells. These studies shed light on the modularity of the GADLEN platform and the tumor cell markers which are important for the therapeutic activity of gamma delta T cell-based engager therapies.

Further information about the Society for Immunotherapy of Cancer Meeting can be found at: . The poster will be available on the  section of the Company’s website shortly after the event.

About Shattuck Labs, Inc.

Shattuck Labs, Inc. (NASDAQ: STTK) is a clinical-stage biotechnology company pioneering the development of bi-functional fusion proteins as a new class of biologic medicine for the treatment of patients with cancer and autoimmune disease. Compounds derived from Shattuck’s proprietary Agonist Redirected Checkpoint, ARC^®, platform simultaneously inhibit checkpoint molecules and activate costimulatory molecules with a single therapeutic. The company’s SL-172154 (SIRPα-Fc-CD40L) program, which is designed to block the CD47 immune checkpoint and simultaneously agonize the CD40 pathway, is being evaluated in multiple Phase 1 trials. A second product candidate, SL-279252 (PD1-Fc-OX40L), is being evaluated in a Phase 1 trial in solid tumors or lymphomas. Additionally, the company is advancing a proprietary Gamma Delta T Cell Engager, GADLEN™, platform, which is designed to bridge gamma delta T cells to tumor antigens for the treatment of patients with cancer. Shattuck has offices in both Austin, Texas and Durham, North Carolina. For more information, please visit: .

The Company intends to use the investor relations portion of its website as a means of disclosing material non-public information and for complying with disclosure obligations under Regulation FD.

Investor Contact:

Conor Richardson

Senior Director, Finance & Investor Relations

Shattuck Labs, Inc.