SQZ Biotechnologies Presents Preclinical Data for their SQZ Tolerizing Antigen Carrier Platform in Antigen-Specific Immune Tolerance (ASIT) Digital Summit Invited Talk

SQZ Biotechnologies SQZ, a cell therapy company developing novel potential treatments for multiple therapeutic areas, announced today that the Immune Tolerance group leader, Shinu John, PhD, will present new preclinical data from the company's Tolerizing Antigen Carriers (SQZ™ TACs) platform in an invited talk at the Antigen-Specific Immune Tolerance (ASIT) Digital Summit taking place January 26, 2021 through January 28, 2021.

SQZ TACs are a red blood cell (RBC)-derived cell therapy candidate being developed as an antigen-specific immune tolerance platform. This platform is designed to leverage the inherently tolerogenic physiological process of RBC clearance to generate immune tolerance against target antigens. Given the flexibility in cargo that the Cell Squeeze® technology is designed to deliver, this approach is potentially applicable to many autoimmune diseases, such as type 1 diabetes and celiac disease, as well as other applications with unwanted immune responses, such as antibody responses against biologics or gene therapy vectors.

Talk Details
Antigen Specific Immune Tolerance Digital Summit
Cell Squeezing RBCs to Create Therapy for Inducing Antigen-Specific Tolerance
Shinu John, PhD
January 27, 2021 at 4:10pm EST
Slide deck available via SQZ Biotechnologies website publications page

The presentation includes novel preclinical data highlighting SQZ TACs and the reduction of antigen-specific CD4 and CD8 T cell activity and increase antigen specific regulatory T cells (T_regs) seen with such candidates to date.

The data demonstrate that SQZ TACs were observed to:

Trigger deletion, or apoptosis, of antigen-specific CD4 and CD8 T cells
Functionally inactivate, or anergize, the remaining antigen-specific CD4 and CD8 T cells
Induce or expand antigen-specific T_regs
Protect mice in a model for type 1 diabetes with evidence of reduced infiltration of pathogenic T cells, increase in antigen-specific T_regs and preservation of insulin producing pancreatic islets.

Also included in the presentation are preclinical mouse data that show:

The rapid uptake of SQZ TACs
The engulfment of SQZ TACs in lymphoid organs where endogenous antigen presentation is most efficient
Specificity of SQZ TAC immune-tolerance against target antigens without broad immune suppression.

"Our goal for the SQZ TAC platform is to create therapies that can selectively suppress the disease driving immune reaction, while allowing the balance of the immune system to function unencumbered," commented Howard Bernstein, MD, PhD, chief scientific officer of SQZ Biotechnologies. "Current approaches rely on broad, chronic immune-suppression which can compromise a patient and put them at long-term risk for infection and even some cancers. Our preclinical data show how SQZ TACs have specifically induced multiple cellular mechanisms of tolerance, which we believe indicate their potential to be developed into impactful therapeutics for many patients."

About SQZ TACs

SQZ TACs are a red blood cell-derived cell therapy candidate being developed as an antigen-specific immune tolerance platform. The platform is designed to leverage the natural process of RBC clearance by professional antigen presenting cells (APCs) in the lymphoid organs, where they engulf aged RBCs and present their components to helper (CD4) and killer (CD8) T cells. This physiological system is tolerogenic by default, instructing the immune system not to mount an attack on red blood cells. SQZ TACs are generated by squeezing RBCs with disease-specific antigen and are made to appear aged. SQZ TACs are designed to be rapidly engulfed in vivo by patient's professional APCs and to act as a "Trojan horse" to drive high quantities of antigen through the tolerogenic RBC clearance process, inducing tolerization of the patient's T cell and antibody responses against the specific target. Potential applications include autoimmune diseases, such as type 1 diabetes and celiac disease, and other applications with unwanted immune responses, such as antibody responses against biologics or gene therapy vectors.

About SQZ Biotechnologies

SQZ Biotechnologies is a clinical-stage biotechnology company developing transformative cell therapies for patients with cancer, infectious diseases, and other serious conditions. Using its proprietary technology, SQZ Biotechnologies offers the unique ability to deliver multiple materials into many patient cell types to engineer what we believe can be an unprecedented range of potential therapeutics for a variety of diseases. SQZ Biotechnologies has the potential to create well-tolerated cell therapies that can provide therapeutic benefit for patients and to improve the patient experience over existing cell therapy approaches. With accelerated production timelines under 24 hours and the opportunity to eliminate preconditioning and lengthy hospital stays, our goal is to use the SQZ™ approach to establish a new paradigm for cell therapies. Our first therapeutic applications aim to leverage the potential to generate target-specific immune responses, both in activation for the treatment of solid tumors and immune tolerance for the treatment of unwanted immune reactions and autoimmune diseases. For more information please visit www.sqzbiotech.com.

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