Abstract B034: A novel immunomodulatory strategy of targeting glyco-immune checkpoints with EAGLE technology

Abstract

Cancer therapy has been revolutionized by inhibiting immune checkpoints to harness the power of the immune system in fighting cancer. However, the majority of patients are resistant to the current immuno-oncology drugs. There is a strong need to identify novel mechanisms of cancer immune evasion and explore novel therapeutic modalities. Glyco-immune checkpoint axis plays a critical role in modulating innate and adaptive immune responses against cancer. However, this pathway is underexplored for therapeutic interventions of cancer, because the complexity and heterogeneity of glycan-ligands on tumor cells pose grand challenges for conventional therapeutic modalities. Here we described a novel multifunctional antibody-like therapeutic modality, named EAGLE (Enzyme-Antibody Glyco-Ligand Editing), which can overcome the heterogeneity and complexity problems and specifically edit tumor-specific glycans. We evaluated the efficacy of an EAGLE molecule and studied its mechanism of actions in a breast cancer EMT6 syngeneic tumor model. Systematic delivery of the EAGLE molecule decreased the expression levels of immunosuppressive glycan-ligands on tumor cell surfaces, and increased T-cell infiltration and activation in the syngeneic tumor models. EAGLE treatment led to 50% complete regressions of established tumors as a monotherapy and 100% cures in combination with an anti-PD1 mAb. Furthermore, cured mice from EAGLE treatment completely rejected the rechallenge of tumor cells, suggesting that EAGLE induced anti-tumor immunologic memory. In summary, the novel therapeutic modality, EAGLE, blocked the glyco-immune checkpoint pathway in the tumor microenvironment and potentiated innate and adaptive antitumor immunity, which offers a novel immunomodulatory strategy to treat cancer. Citation Format: Li Peng. A novel immunomodulatory strategy of targeting glyco-immune checkpoints with EAGLE technology [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr B034.