Abstract 1888: IAE0972, A novel EGFR/IL10 immunocytokine of monovalent anti-EGFR antibody fused with IL10 homodimer

Abstract Exhaustion of immune cells in the tumor microenvironment has been found and confirmed in many tumor cases, accounting for the major problems of current PD1/L1-oriented immunotherapy. There are two types of exhausted T cells present in the tumor microenvironment: progenitor exhausted T cells and terminally exhausted T cells. Data from various mouse syngeneic tumor models suggest that the dominance of progenitor exhausted T cells will be replaced by terminally exhausted T cells as the tumor progresses. The PD1/PDL1 antibodies mainly act on progenitor exhausted T cells and can develop acquired resistance as terminally exhausted T cells become the dominant cells in the tumor microenvironment. Recently, there are studies demonstrating that IL10 can restore the oxidative phosphorylation metabolism of terminally exhausted T cells and restore their potent killing activities of tumor cells. We therefore designed IAE0972, a novel EGFR/IL10 immunocytokine to solve the problems of immune cell exhaustion in current immunotherapy. It is a monovalent anti-EGFR antibody fused with IL10 homodimer. The anti-EGFR antibody can specifically enrich IAE0972 in tumor microenvironment, so that IL10 can reinvigorate antigen specific CD8+ T cells and facilitate its proliferation, while preserving the tumor cell proliferation inhibition activities of EGFR antibody. The design of monovalent form anti-EGFR antibody can also avoid the skin toxicity problem. In this study, we studied the target binding activity, CD8+ T cell activation activity and cancer cell proliferation inhibition activity of IAE0972. We also observed a much higher anti-tumor efficacy of IAE0972 in a MC38 syngeneic tumor model compared with that of Cetuximab. In addition, the molecule has a very good safety profile with MTD over 6 mg/kg and no skin toxicities, which is about 300-fold higher than that of cytokine drugs. In summary, IAE0972 is an innovative EGFR/IL10 immunocytokine with robust preclinical anti-tumor efficacy and favorable safety profile, which has the potential to address acquired resistance of current immunotherapy. IAE0972 is the first EGFR/IL10 immunocytokine with IND approval from both FDA and NMPA. The indications of IAE0972 include colorectal cancer, head and neck squamous cell carcinoma, squamous non-small cell lung cancer, and other EGFR positive tumors. A Phase I/IIa clinical trial to evaluate the safety, tolerability and preliminary efficacy of IAE0972 in patients with locally advanced or metastatic malignant tumors is on-going (NCT05396339). Citation Format: Liusong Yin, Xiaoling Jiang, Chongbing Wu, Zi Chen. IAE0972, A novel EGFR/IL10 immunocytokine of monovalent anti-EGFR antibody fused with IL10 homodimer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1888.