Abstract LB342: Potent Anti-Tumor Activity Demonstrated by Anti-AXL CAR T Cell Therapy and AXL-ADC in Lung Cancer and Breast Cancer Models

Abstract AXL is over-expressed in various cancers. Its signaling pathway is related to tumor progress. We created a novel a novel AXL-ADC (Hu002-MMAE) based on humanized AXL-targeted antibody (Hu002). We also developed anti-AXL CAR T cells and AXL-CAR iNKT to evaluate anti-tumor effect. Methods: 1) Evaluate the cytotoxicity of Hu002-MMAE in 5 AXL-high-expressing cells. 2) in vivo efficacy validation of Hu002-MMAE into LCLC-103H-bearing Nude mice and U87MG-bearing nude mice. 3) Evaluate the cytotoxicity of anti-AXL CAR-T and AXL CAR-iNKT cells in cell lines with different AXL expression levels to validate the selectivity. 4) in vivo efficacy validation of anti-AXL CAR T cells into MDA-MB-231-bearing mice.Results: Hu002 demonstrates potent binding affinity significantly inhibited the migration of AXL-high tumor cells. The Hu002-MMAE showed potent cytotoxicity against AXL-high tumor cells (IC50 < 0.1 nmol/L) and had a longer-term therapeutic effect in a variety of NSCLC and glioma tumors in vivo (MED < 0.5 mg/kg). Anti-AXL CAR-T cells and AXL CAR-iNKT exhibited strong killing activity to AXL-high-expressed cell lines LCLC-103H and MDA-MB-231 in vitro, while shows minimum effect of anti-tumor effect in AXL-low-expressed cell lines H460 and MDA-MB-453. In in vivo models of MDA-MB-231, we observed increased infiltration of T cells in primary tumor and reduced lung metastasis after AXL CAR-T treamtment.Conclusion: Anti-AXL CAR T and AXL-ADC cells showed strong and selective killing activity, improved TME in primary tumor and mitigate lung metastasis, which makes it a potential strategy for cancers. Citation Format: Zhongen Wu, Yang Gao, Jingpeng Pei, Enfeng Zhao, Shenglin Mei, Yuxiong Feng, Di Zhu. Potent Anti-Tumor Activity Demonstrated by Anti-AXL CAR T Cell Therapy and AXL-ADC in Lung Cancer and Breast Cancer Models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB342.