SQZ Biotechnologies Publishes Preclinical Research Demonstrating SQZ® AAC Platform’s Potential as an Effective Red Blood Cell-Derived Immunotherapy

On October 3, 2022 SQZ Biotechnologies Company (NYSE: SQZ), focused on unlocking the full potential of cell therapies for multiple therapeutic areas, reported the publication of preclinical research on the SQZ Activating Antigen Carrier (AAC) platform (Press release, SQZ Biotech, OCT 3, 2022, View Source [SID1234621644]). The data, published in Frontiers in Immunology, demonstrated that the company’s Cell Squeeze platform can be used to generate AACs by engineering red blood cells (RBCs) with antigen and adjuvant that can drive antigen-specific activation of T cells both in mouse in vivo and human in vitro systems. The study also used a mouse tumor model to show that the efficacy of the AAC therapy could be further enhanced by combining with the chemotherapeutic agent, Cisplatin.

Schedule your 30 min Free 1stOncology Demo!
Discover why more than 1,500 members use 1stOncology™ to excel in:

Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing

                  Schedule Your 30 min Free Demo!

"This paper demonstrates the potential of our technology to generate an effective red blood cell-derived cancer immunotherapy," said Howard Bernstein, M.D., Ph.D., Chief Scientific Officer at SQZ Biotechnologies. "The ability of the Cell Squeeze platform to engineer RBCs to leverage the natural process of RBC clearance for T cell activation represents a promising new therapeutic approach to cancer treatment. We look forward to building on these preclinical results in our ongoing Phase 1/2 clinical trial."

The company’s engineered RBCs are designed to transport their cargo of antigen and adjuvant to professional antigen presenting cells (APCs) in the body. The published data demonstrate that when these professional APCs process the engineered RBC, they present the desired antigen to endogenous T cells and drive their activation. This approach to generate RBC therapeutics could be tailored to deliver a variety of antigen and adjuvant materials, and other possible agents, to potentially enhance different aspects of anti-tumor immunity.

"We are excited about the preclinical findings of our AAC program, which has shown potential in both monotherapy settings and in combination with chemotherapy," said Scott Loughhead, Ph.D., VP of Translational Research at SQZ Biotechnologies. "AACs represent a truly differentiated approach that offers the opportunity for broad applicability across solid tumor types."

Study Findings:

Generation of AACs: Investigators used the Cell Squeeze technology to engineer RBCs with E6 and E7 antigens and the adjuvant, poly I:C. This process generates AACs that resemble aged RBCs which triggers rapid clearance by professional APCs.
Effective Delivery to APCs: The method leverages the natural process of RBC clearance to deliver tumor antigens to endogenous professional APCs without the use of chemical or viral vectors.
Antigen-Specific Activation of T cells: AAC uptake, antigen processing, and presentation by APCs drove antigen-specific activation of T cells in mouse in vivo and human in vitro systems. In a mouse model of HPV16+ tumors, AAC therapy demonstrated significant anti-tumor effects including 12-fold improvement in CD8+ T cell infiltration and 900-fold improvement in E7 antigen-specific CD8+ T cell infiltration compared to untreated animals.
Enhanced Efficacy with Addition of Cisplatin: The combination of AAC therapy and the chemotherapeutic agent Cisplatin, a common treatment for HPV-driven tumors, increased the efficacy of the treatment in a preclinical tumor model.
About SQZ-AAC-HPV
SQZ AACs are generated by squeezing red blood cells (RBCs) with antigens and activating adjuvant. The process is tuned to make the engineered RBCs appear aged. Once administered to patients, SQZ AACs aim to be rapidly taken up by professional antigen presenting cells through a natural process to destroy aged RBCs in the body known as eryptosis. After being taken up, the encapsulated antigen and adjuvant within SQZ AACs is released, allowing for antigen processing and maturation of professional, endogenous antigen presenting cells in the lymphoid organs, and drives subsequent activation of HPV-specific T cells. SQZ-AAC-HPV is the first product candidate from the SQZ AAC platform.

About Human Papillomavirus Positive Cancers
Human papillomavirus (HPV) is one of the most common viruses worldwide and certain strains persist for many years, often leading to cancer. According to the Centers for Disease Control (CDC), in the United States HPV+ tumors represent 3% of all cancers in women and 2% of all cancers in men, resulting in over 39,000 new cases of HPV+ tumors every year. HPV infection is larger outside of the U.S., and according to the International Journal of Cancer, HPV+ tumors account for 4.5% of all cancers worldwide resulting in approximately 630,000 new cases every year. According to the CDC, HPV infection plays a significant role in the formation of more than 90% of anal and cervical cancers, and most cases of vaginal (75%), oropharyngeal (70%), vulval (70%) and penile (60%) cancers.