Abstract 4655: Targeting FAK improves the tumor penetration of antibody-drug conjugates to strengthen the anti-cancer responses

Abstract Antibody-drug conjugates (ADCs) such as HER2 ADC Enhertu and TROP2 ADC Trodelvy have been proved to be the promising therapeutic agents in portion of cancer diseases. However, there are still numerous patients refractory to the therapy, indicating that the efficacy of ADCs may need to be further optimized. Here, we report that the excessive cancer-associated fibroblasts (CAFs) can serve as a fibrotic barrier, to the detriment of anti-tumor effects from ADCs by alleviating their tissue penetration. Mechanistically, the cancer cells can transform the normal fibrotic cells into CAFs which are featured by the hyperactivated focal adhesion kinase (FAK) signaling. The fast-growing CAFs would decrease the tumor uptake of the big molecules, conferring drug resistance of ADCs to the cancer cells. Targeting FAK with a small molecule inhibitor IN10018 is capable to reduce CAFs associated tumor barrier, elevating the tissue penetration of different types of ADCs regardless their respective targets. The combination regimen comprising IN10018 and the ADCs targeting either HER2 or TROP2 outperformed each monotherapy with respect to antitumor outcomes in different animal experiments. The preclinical evidence for the dual regimen of IN10018 and ADCs warrants a further validation in clinical settings. Citation Format: Baoyuan Zhang, Zhixiang Zhang, Jiaming Gao, Shiqiang Lu, Ran Pang, Dongfang Li, Xun Huang, Natasha Qin, Leo Liu, Zaiqi Wang. Targeting FAK improves the tumor penetration of antibody-drug conjugates to strengthen the anti-cancer responses abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts) ; 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84 (6Suppl): Abstract nr 4655.