{
  "abstract": "Background OX40, a key co-stimulatory receptor that amplifies T cell-mediated anti-tumor immunity, is a promising immunotherapeutic target. Despite most reported OX40 agonists in clinical trials having high affinity, the relationship between affinity and agonistic activity remains complex, necessitating further clarification of affinity’s impact on OX40-based immunotherapy efficacy and its underlying mechanisms.Methods We generated the different affinity OX40 agonist antibodies were generated by phage display. Antibody-receptor interactions were modeled using AI-based prediction and validated by hydrogen-deuterium exchange. We assessed the receptor clustering, T cell activation, and regulatory T cell (Treg) depletion effect of OX40 antibodies with different affinities by confocal microscopy and reporter cell assays. We further evaluated the anti-tumor efficacy in multiple murine tumor models. The effects of HFB301001 treatment on tumor-infiltrating T cells, safety in cynomolgus monkeys, and immune activation in clinical samples were investigated using single-cell RNA sequencing (scRNA-seq), flow cytometry, ELISpot, and immunofluorescence.Results We identified the low-affinity OX40 agonist antibody HFB301001 and generated variants with different affinities via phage display. Compared with its high-affinity mutant, HFB301001 induced stronger receptor clustering, enhanced T cell activation, and mediated more potent natural killer-mediated antibody-dependent cell-mediated cytotoxicity for Treg depletion than its high-affinity mutant in vitro. Consistently, HFB301001 outperformed the high-affinity mutant by boosting intratumoral T cell infiltration/activation and Treg clearance in vivo. Additionally, HFB301001 exhibited favorable safety in cynomolgus monkeys and effectively activated tumor-infiltrating T cells in a clinically relevant tumor slice culture system.Conclusions The reduced-affinity strategy represents a promising framework for the clinical development of OX40-targeted cancer immunotherapies. Currently, HFB301001 is concluding in a phase I clinical study involving patients with advanced solid tumors ( NCT05229601).",
  "authors": [
    {
      "affiliations": [
        "State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences and Frontiers Science Center for Cell Responses, Academy for Advanced Interdisciplinary Studies, Nankai University, Tianjin, China"
      ],
      "name": "Jiliang Zhao"
    },
    {
      "affiliations": [
        "State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences and Frontiers Science Center for Cell Responses, Academy for Advanced Interdisciplinary Studies, Nankai University, Tianjin, China"
      ],
      "name": "Dongping Zhang"
    },
    {
      "affiliations": [
        "HiFiBiO Therapeutics, Cambridge, Massachusetts, USA"
      ],
      "name": "Yun-Yueh Lu"
    },
    {
      "affiliations": [
        "Central Laboratory, Affiliated Hospital of Changzhi Medical College, Changzhi People’s Hospital, Changzhi, Shanxi, China"
      ],
      "name": "Ruina Jin"
    },
    {
      "affiliations": [
        "State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences and Frontiers Science Center for Cell Responses, Academy for Advanced Interdisciplinary Studies, Nankai University, Tianjin, China"
      ],
      "name": "Fan Li"
    },
    {
      "affiliations": [
        "State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences and Frontiers Science Center for Cell Responses, Academy for Advanced Interdisciplinary Studies, Nankai University, Tianjin, China"
      ],
      "name": "Zhaoyuan Zhang"
    },
    {
      "affiliations": [
        "NITFID, School of Statistics and Data Science, AAIS, LPMC and KLMDASR, Nankai University, Tianjin, China"
      ],
      "name": "Wentao Ni"
    },
    {
      "affiliations": [
        "State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences and Frontiers Science Center for Cell Responses, Academy for Advanced Interdisciplinary Studies, Nankai University, Tianjin, China"
      ],
      "name": "Nanxin Gong"
    },
    {
      "affiliations": [
        "State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences and Frontiers Science Center for Cell Responses, Academy for Advanced Interdisciplinary Studies, Nankai University, Tianjin, China"
      ],
      "name": "Yi Wang"
    },
    {
      "affiliations": [
        "State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences and Frontiers Science Center for Cell Responses, Academy for Advanced Interdisciplinary Studies, Nankai University, Tianjin, China"
      ],
      "name": "Zhongqian Yin"
    },
    {
      "affiliations": [
        "State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences and Frontiers Science Center for Cell Responses, Academy for Advanced Interdisciplinary Studies, Nankai University, Tianjin, China"
      ],
      "name": "Yazhuo Du"
    },
    {
      "affiliations": [
        "State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences and Frontiers Science Center for Cell Responses, Academy for Advanced Interdisciplinary Studies, Nankai University, Tianjin, China"
      ],
      "name": "Wenxuan Ma"
    },
    {
      "affiliations": [
        "State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences and Frontiers Science Center for Cell Responses, Academy for Advanced Interdisciplinary Studies, Nankai University, Tianjin, China"
      ],
      "name": "Xiaoqian Wang"
    },
    {
      "affiliations": [
        "Department of Lung Cancer Surgery, Tianjin Key Laboratory of Lung Cancer Metastasis and Tumor Microenvironment, Lung Cancer Institute, Tianjin Medical University General Hospital, Tianjin, Tianjin, China"
      ],
      "name": "Lingling Zu"
    },
    {
      "affiliations": [
        "State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences and Frontiers Science Center for Cell Responses, Academy for Advanced Interdisciplinary Studies, Nankai University, Tianjin, China",
        "Institute of Transplantation Medicine, Nankai University, Tianjin First Central Hospital, Tianjin, China"
      ],
      "name": "Shiyu Liu"
    },
    {
      "affiliations": [
        "State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences and Frontiers Science Center for Cell Responses, Academy for Advanced Interdisciplinary Studies, Nankai University, Tianjin, China"
      ],
      "name": "Kailu Yang"
    },
    {
      "affiliations": [
        "State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences and Frontiers Science Center for Cell Responses, Academy for Advanced Interdisciplinary Studies, Nankai University, Tianjin, China"
      ],
      "name": "Yiyang Bai"
    },
    {
      "affiliations": [
        "HiFiBiO Therapeutics, Cambridge, Massachusetts, USA"
      ],
      "name": "Jinping Gan"
    },
    {
      "affiliations": [
        "HiFiBiO Therapeutics, Cambridge, Massachusetts, USA"
      ],
      "name": "Francisco Adrian"
    },
    {
      "affiliations": [
        "State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences and Frontiers Science Center for Cell Responses, Academy for Advanced Interdisciplinary Studies, Nankai University, Tianjin, China"
      ],
      "name": "Zhangyong Hong"
    },
    {
      "affiliations": [
        "State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences and Frontiers Science Center for Cell Responses, Academy for Advanced Interdisciplinary Studies, Nankai University, Tianjin, China"
      ],
      "name": "Sihe Zhang"
    },
    {
      "affiliations": [
        "Jecho Biopharmaceuticals Co., Ltd, Tianjin, China"
      ],
      "name": "Yunsong Chang"
    },
    {
      "affiliations": [
        "Jecho Biopharmaceuticals Co., Ltd, Tianjin, China"
      ],
      "name": "Zhenyu Wang"
    },
    {
      "affiliations": [
        "Department of Lung Cancer Surgery, Tianjin Key Laboratory of Lung Cancer Metastasis and Tumor Microenvironment, Lung Cancer Institute, Tianjin Medical University General Hospital, Tianjin, Tianjin, China"
      ],
      "name": "Xin Jin"
    },
    {
      "affiliations": [
        "Department of Lung Cancer Surgery, Tianjin Key Laboratory of Lung Cancer Metastasis and Tumor Microenvironment, Lung Cancer Institute, Tianjin Medical University General Hospital, Tianjin, Tianjin, China"
      ],
      "name": "Jianguo Zhong"
    },
    {
      "affiliations": [
        "Department of Lung Cancer Surgery, Tianjin Key Laboratory of Lung Cancer Metastasis and Tumor Microenvironment, Lung Cancer Institute, Tianjin Medical University General Hospital, Tianjin, Tianjin, China"
      ],
      "name": "Kunkun Ge"
    },
    {
      "affiliations": [
        "Department of Lung Cancer Surgery, Tianjin Key Laboratory of Lung Cancer Metastasis and Tumor Microenvironment, Lung Cancer Institute, Tianjin Medical University General Hospital, Tianjin, Tianjin, China"
      ],
      "name": "Sibo Peng"
    },
    {
      "affiliations": [
        "State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences and Frontiers Science Center for Cell Responses, Academy for Advanced Interdisciplinary Studies, Nankai University, Tianjin, China"
      ],
      "name": "Dan Ding"
    },
    {
      "affiliations": [
        "NITFID, School of Statistics and Data Science, AAIS, LPMC and KLMDASR, Nankai University, Tianjin, China"
      ],
      "name": "Wei Zheng"
    },
    {
      "affiliations": [
        "Department of Lung Cancer Surgery, Tianjin Key Laboratory of Lung Cancer Metastasis and Tumor Microenvironment, Lung Cancer Institute, Tianjin Medical University General Hospital, Tianjin, Tianjin, China"
      ],
      "name": "Song Xu"
    },
    {
      "affiliations": [
        "Shanghai Institute for Advanced Immunochemical Studies, ShanghaiTech University, Shanghai, China"
      ],
      "name": "Wei Wang"
    },
    {
      "affiliations": [
        "HiFiBiO Therapeutics, Cambridge, Massachusetts, USA"
      ],
      "name": "Liang Schweizer"
    },
    {
      "affiliations": [
        "State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences and Frontiers Science Center for Cell Responses, Academy for Advanced Interdisciplinary Studies, Nankai University, Tianjin, China"
      ],
      "name": "Hongkai Zhang"
    }
  ],
  "title": "HFB301001, an OX40-based immunotherapy, drives Treg clearance and CTL activation through optimized OX40 receptor clustering",
  "uid": "93cc3192-11a1-5e38-9d8a-373173a0993e"
}