2区 · 医学
ArticleOA
作者: Jiang, Wenqing ; Jung, Jaeho ; Won, Jonghwa ; Kim, Hyunjoo ; Jeon, Jaehyoung ; Wang, Zhengyi ; Kim, Youngkwang ; Park, Su-Hyung ; Fang, Lei ; Son, Yong-Gyu ; Hwang, Shin ; Shin, Eui-Cheol ; Lim, Yangmi ; Jeon, Minwoo ; Sung, Eunsil ; Jeong, Seongju ; Lee, Shinai ; Lee, Hanbyul ; Hong, Youngeun ; Jung, Ui-Jung ; Park, Eunyoung ; Kim, Hyung-Don
Background:Stimulation of 4-1BB with agonistic antibodies is a promising strategy for improving the therapeutic efficacy of immune checkpoint inhibitors (ICIs) or for overcoming resistance to ICIs. However, dose-dependent hepatotoxicity was observed in clinical trials with monoclonal anti-4-1BB agonistic antibodies due to the activation of 4-1BB signaling in liver resident Kupffer cells.
Methods:To avoid this on-target liver toxicity, we developed a novel bispecific antibody (4-1BB×PD-L1 bispecific antibody, termed “ABL503”) uniquely designed to activate 4-1BB signaling only in the context of PD-L1, while also blocking PD-1/PD-L1 signaling.
Results:Functional evaluation using effector cells expressing both 4-1BB and PD-1 revealed superior biological activity of ABL503 compared with the combination of each monoclonal antibody. ABL503 also augmented T-cell activation in in vitro assays and further enhanced the anti-PD-L1-mediated reinvigoration of tumor-infiltrating CD8+ T cells from patients with cancer. Furthermore, in humanized PD-L1/4-1BB transgenic mice challenged with huPD-L1-expressing tumor cells, ABL503 induced superior anti-tumor activity and maintained an anti-tumor response against tumor rechallenge. ABL503 was well tolerated, with normal liver function in monkeys.
Conclusion:The novel anti-4-1BB×PD-L1 bispecific antibody may exert a strong anti-tumor therapeutic efficacy with a low risk of liver toxicity through the restriction of 4-1BB stimulation in tumors.