An Fc-muted bispecific antibody targeting PD-L1 and 4-1BB induces antitumor immune activity in colorectal cancer without systemic toxicity

Cellular & Molecular Biology Letters

Research

Wu Yin¹  Guodong Shen¹  Lian-sheng Cheng²  Qing Fang³  Wen-ting Liu³  Xiaoli Zeng³  Fengrong Wang³  Pengfei Zhou³  Dayan Zhang³  Qun Zhao³  Yan Zhang⁴  Zhongliang Zhu⁵  Yan Gao⁵  Liwen Niu⁵  Min Zhu⁵ 

[1] Department of Geriatrics, The First Affiliated Hospital of University of Science and Technology of China, Gerontology Institute of Anhui Province, Division of Life Sciences and Medicine, University of Science and Technology of China, 230001, Hefei, Anhui, China;Anhui Provincial Key Laboratory of Tumor Immunotherapy and Nutrition Therapy, 230001, Hefei, Anhui, China;Department of Geriatrics, The First Affiliated Hospital of University of Science and Technology of China, Gerontology Institute of Anhui Province, Division of Life Sciences and Medicine, University of Science and Technology of China, 230001, Hefei, Anhui, China;Hefei HankeMab Biotechnology Limited, 230088, Hefei, Anhui, China;Anhui Provincial Key Laboratory of Tumor Immunotherapy and Nutrition Therapy, 230001, Hefei, Anhui, China;Anhui Province Key Laboratory of Gene Engineering Pharmaceutical, Biomedicine Technology Innovation Center of Hefei, Anhui Anke Biotechnology (Group) Co., Ltd., 230088, Hefei, Anhui, China;Hefei HankeMab Biotechnology Limited, 230088, Hefei, Anhui, China;School of Health Service Management, Anhui Medical University, 230032, Hefei, Anhui, China;School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, 230026, Hefei, Anhui, China;

关键词: Colorectal cancer;    Cancer immunotherapy;    4-1BB/CD137;    PD-1/PD-L1;    Immune checkpoint inhibitor;    Antitumor immunity;   

DOI  :  10.1186/s11658-023-00461-w

 received in 2023-01-12, accepted in 2023-05-15,  发布年份 2023

来源: Springer

【 摘 要 】

BackgroundResistance to immune checkpoint inhibitor (ICI) therapy narrows the efficacy of cancer immunotherapy. Although 4-1BB is a promising drug target as a costimulatory molecule of immune cells, no 4-1BB agonist has been given clinical approval because of severe liver toxicity or limited efficacy. Therefore, a safe and efficient immunostimulatory molecule is urgently needed for cancer immunotherapy.MethodsHK010 was generated by antibody engineering, and the Fab/antigen complex structure was analyzed using crystallography. The affinity and activity of HK010 were detected by multiple in vitro bioassays, including enzyme-linked immunosorbent assay (ELISA), surface plasmon resonance (SPR), flow cytometry, and luciferase-reporter assays. Humanized mice bearing human PD-L1-expressing MC38 (MC38/hPDL1) or CT26 (CT26/hPDL1) tumor transplants were established to assess the in vivo antitumor activity of HK010. The pharmacokinetics (PK) and toxicity of HK010 were evaluated in cynomolgus monkeys.ResultsHK010 was generated as an Fc-muted immunoglobulin (Ig)G4 PD-L1x4-1BB bispecific antibody (BsAb) with a distinguished Fab/antigen complex structure, and maintained a high affinity for human PD-L1 (KD: 2.27 nM) and low affinity for human 4-1BB (KD: 493 nM) to achieve potent PD-1/PD-L1 blockade and appropriate 4-1BB agonism. HK010 exhibited synergistic antitumor activity by blocking the PD-1/PD-L1 signaling pathway and stimulating the 4-1BB signaling pathway simultaneously, and being strictly dependent on the PD-L1 receptor in vitro and in vivo. In particular, when the dose was decreased to 0.3 mg/kg, HK010 still showed a strong antitumor effect in a humanized mouse model bearing MC38/hPDL1 tumors. Strikingly, HK010 treatment enhanced antitumor immunity and induced durable antigen-specific immune memory to prevent rechallenged tumor growth by recruiting CD8+ T cells and other lymphocytes into tumor tissue and activating tumor-infiltrating lymphocytes. Moreover, HK010 not only did not induce nonspecific production of proinflammatory cytokines but was also observed to be well tolerated in cynomolgus monkeys in 5 week repeated-dose (5, 15, or 50 mg/kg) and single-dose (75 or 150 mg/kg) toxicity studies.ConclusionWe generated an Fc-muted anti-PD-L1x4-1BB BsAb, HK010, with a distinguished structural interaction with PD-L1 and 4-1BB that exhibits a synergistic antitumor effect by blocking the PD-1/PD-L1 signaling pathway and stimulating the 4-1BB signaling pathway simultaneously. It is strictly dependent on the PD-L1 receptor with no systemic toxicity, which may offer a new option for cancer immunotherapy.

【 授权许可】

CC BY   
© The Author(s) 2023

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