SaefCAR: Regulatable CAR-T cells for safe and effective immunotherapy

SaefCAR：可调节的 CAR-T 细胞用于安全有效的免疫治疗

基本信息

批准号：
10759600
负责人：
Yemi Onakunle
金额：
$ 40万
依托单位：
MABSWITCH, INC.
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-09-19 至 2024-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10759600
关键词：
Address Adverse event Affinity Animal Model Antibodies Antigen Targeting Antigens Architecture Binding Biological Products CAR T cell therapy CD19 gene Calmodulin Cell Line Cells Clinical DNA Discrimination Disease Dose Engineering Equilibrium FDA approved Flow Cytometry Future Hematologic Neoplasms Human Immunoglobulin Fragments Immunotherapy In Vitro Letters Libraries Ligands Modality Patients Peptides Phase Physiological Proteins Reaction Time Regulation Reporter Retroviral Vector Risk Safety Serious Adverse Event Signal Transduction Signal Transduction Induction Small Business Innovation Research Grant Solid Neoplasm Specificity T-Cell Activation T-Lymphocyte Technology Tissues Toxic effect Tumor Antigens Tumor Lysis Syndrome Variant Work Writing antigen binding cancer immunotherapy cancer type chimeric antigen receptor chimeric antigen receptor T cells clinical translation cytokine cytokine release syndrome delivery vehicle design engineered T cells exhaustion experience improved in vivo neurotoxicity preclinical development premature prevent screening small molecule success systemic toxicity tumor

项目摘要

Project Summary: Despite the remarkable success in the treatment of some hematological cancers, the risk of serious adverse events and loss of potency remain major problems that threaten to curtail widespread application of chimeric antigen receptor (CAR) T-cell therapies to other cancer types including solid tumors. These problems, all of which are influenced by the binding affinity of the CAR targeting domain, result from the propensity for unpredictable hyperactivation that can lead to potentially fatal systemic toxicities such as cytokine release syndrome (CRS), tumor lysis syndrome (TLS) and neurotoxicity. Furthermore, on-target off-tumor toxicities can result from the indiscriminate binding of constitutively expressed CARs to tumor antigens on healthy tissues, whilst disease relapses can occur due to antigen escape and/or T cell exhaustion. Current and emerging CAR- T cell strategies and designs to address these problems are often too slow in terms of response times and onset of action. Furthermore, they prematurely and permanently eliminate the “high value” cells and often require the expression of additional proteins which may constrain the DNA payload capacity of current lenti- and retro- virus vectors. There is thus an urgent unmet need for in-vivo regulatable CAR-T cell platforms that are rapid, reversible and don’t exert a substantial DNA burden on the CAR delivery vector. The objective of this proposal is to assess the feasibility to regulate the activation, effector functions and cytokine release of CAR T-cells using an exogenously administered ligand that modulates the affinity of the CAR T-cell targeting domain. To this end we will utilize our proprietary universal allosteric-linker and switch module for antibodies (UNASMA) technology to incorporate an ON/OFF affinity switch into a well characterized antibody single chain variable fragment (scFv) against a clinically validated hematological cancer target which will subsequently be formatted as a switchable affinity chimeric antigen receptor (SaefCAR). We postulate that the resulting SaefCAR following transduction into a T-cell, will enable the in-vivo regulation of the SaefCAR T-cells’ activity via exogenous administration of a small molecule or peptide ligand, potentially solving several of the problems of current CAR-T cell therapies by: 1) Ameliorating intrinsic toxicities via enablement of a slow start to T-cell activation, 2) Preventing on-target off- tumor toxicities by switching off the CAR-T cell without eliminating it 3) Preventing exhaustion of tumor-specific CAR T cells caused by tonic signaling and other mechanisms via intermittent ON/OFF switching of the CAR. Specifically in Aim 1 we will develop switchable forms of the scFv which will subsequently be formatted into a CAR and transduced into a T-cell in Aim 2. In Aim 3 we will validate proof-of-concept of the regulated SaefCAR T-cells in in-vitro and in-vivo studies. We aim to demonstrate that a ligand-controllable affinity switch in the binding domain of SaefCAR T-cells can regulate it’s activation and effector functions against a tumor. Importantly due to the universal character of our approach, it provides a blueprint to improve any scFv-based CAR T-cell therapy in the future by adding a capability to regulate the CAR affinity for the tumor antigen.

项目概要：尽管在治疗一些血液癌症方面取得了显着的成功，但严重不良反应的风险事件和效力丧失仍然是威胁限制嵌合体广泛应用的主要问题抗原受体 (CAR) T 细胞疗法治疗包括实体瘤在内的其他癌症类型。其受到 CAR 靶向结构域的结合亲和力的影响，是由于倾向于不可预测的过度激活，可能导致潜在致命的全身毒性，例如细胞因子释放综合征（CRS）、肿瘤溶解综合征（TLS）和神经毒性此外，靶向肿瘤外毒性也可能发生。由于组成型表达的 CAR 与健康组织上的肿瘤抗原不加区别地结合，而由于抗原逃逸和/或 T 细胞耗竭，当前和新兴的 CAR- 可能会导致疾病复发。解决这些问题的 T 细胞策略和设计在响应时间和起效方面往往太慢此外，它们会过早且永久地消除“高价值”细胞，并且通常需要额外蛋白质的表达可能会限制当前慢病毒和逆转录病毒的 DNA 负载能力因此，对快速、可逆的体内可调节 CAR-T 细胞平台的迫切需求尚未得到满足。并且不要对 CAR 递送载体施加大量 DNA 负担该提案的目的是评估。使用调节 CAR T 细胞的激活、效应功能和细胞因子释放的可行性外源施用的配体调节 CAR T 细胞靶向结构域的亲和力。将利用我们专有的抗体通用变构连接器和开关模块 (UNASMA) 技术将 ON/OFF 亲和开关整合到已充分表征的抗体单链可变片段 (scFv) 中针对经过临床验证的血液癌症目标，该目标随后将被格式化为可切换的我们假设转导后产生的 SaefCAR。进入 T 细胞，将能够通过外源性施用对 SaefCAR T 细胞的活性进行体内调节小分子或肽配体，可能通过以下方式解决当前 CAR-T 细胞疗法的几个问题： 1) 通过缓慢启动 T 细胞激活来改善内在毒性，2) 防止脱靶通过关闭 CAR-T 细胞而不消除它来消除肿瘤毒性 3) 防止肿瘤特异性耗尽 CAR T 细胞由强直信号传导和其他机制通过 CAR 的间歇性开/关切换引起。在目标 1 中，我们将开发 scFv 的可切换形式，随后将其格式化为在目标 2 中将 CAR 转导到 T 细胞中。在目标 3 中，我们将验证受监管的 SaefCAR 的概念验证我们的目标是证明 T 细胞在体外和体内研究中存在配体可控的亲和开关。重要的是，SaefCAR T 细胞的结合域可以调节其针对肿瘤的激活和效应功能。由于我们方法的通用性，它提供了改进任何基于 scFv 的 CAR T 细胞的蓝图通过添加调节 CAR 对肿瘤抗原亲和力的能力，可以在未来的治疗中发挥作用。