Proj 4 - Enhancing the Potency and Durability of Immunotherapies

最近的进展已经证明免疫疗法是一种有效的抗癌治疗方式。但随着 除了高危神经母细胞瘤（NB），免疫治疗尚未显示出改善预后， 患有实体瘤的儿童。对于接受清髓性治疗和自体移植的NB患者， 造血干细胞移植，随后用dinutuximab治疗，其靶向 二唾液酸神经节苷脂（GD 2）对NB细胞的作用，将2年无事件生存率从46±5%提高到66± 5%。然而，在这方面， 40%的患者在接受dinutuximab治疗期间或之后复发;方案相关毒性较高; 15%的患者在接受dinutuximab治疗期间或之后复发。 患者具有早期疾病进展并且不接受该疗法。其他免疫疗法包括 使用嵌合抗原受体（CAR）修饰的T细胞的过继性细胞疗法和使用 单克隆抗体（mAb）。CAR T细胞对小儿急性淋巴细胞白血病具有有效的活性 白血病，但尚未显示出抗实体瘤的活性。单独的检查点抑制（例如，反对 PD-1 mAb）可能不具有显著的抗NB活性，因为其功效与频繁的肿瘤细胞凋亡相关。 突变和NB中突变的缺乏。我们的战略重点是基于细胞和mAb的 用于NB的免疫疗法不需要高水平的固有免疫原性， 我们对肿瘤细胞认识的进展：免疫系统界面。我们假设， 如果策略既能增强CAR T细胞的细胞内在功能，又能激活NK（aNK）， 细胞，并克服肿瘤微环境（TME）中的细胞外源性免疫抑制。我们的具体 目的是增强CAR T细胞和aNK细胞的效力和耐久性，并开发出 将增强的细胞疗法与免疫抑制性TME的调节联合收割机组合。我们的研究 策略/方法是1）使用GD 2-CAR的靶向诱变增强GD 2-CAR的效力和耐久性， scFv以防止源自scFv的抗原非依赖性紧张性信号传导和耗竭; 具有已证实活性的B7-H3-CAR;并添加PD-1阻断剂以增强效力并限制耗竭; 2） 通过将aNK细胞与抗GD 2和抗B7-H3组合，增加aNK细胞的运输、持久性和效力 mAb和超激动剂IL-15;和3）用抗-CD 105克服TME中的免疫抑制 mAb抑制/消除间充质基质和内皮细胞，CSF 1 R抑制剂消除 抑制性MDSC和TAM（与项目4合作），使用TGFBR 1抑制剂，以防止 TGFβ1，并用FAK/ALK抑制剂克服基于FAK诱导的T细胞抑制和耗竭 （项目1）。总之，本发明提供了增强本发明化合物的效力和耐久性的新方法。 将开发过继性T细胞和NK细胞疗法，用于核心B开展的临床试验 (NANT财团）的高风险NB患者。

Recent advances have credentialed immunotherapy as a potent anti-cancer treatment modality. However, with exception of high-risk neuroblastoma (NB), immunotherapy has not yet been shown to improve outcomes for children with solid tumors. For patients with NB undergoing myeloablative therapy and autologous hematopoietic stem cell transplantation, subsequent treatment with dinutuximab, which targets disialoganglioside (GD2) on NB cells, improves 2-year event-free survival from 46±5% to 66±5%. However, 40% of patients relapse during or after receiving dinutuximab; regimen-related toxicity is high; and 15% of patients have early disease progression and do not receive this therapy. Other immunotherapies include adoptive cell therapy with chimeric antigen receptor (CAR) modified T cells and checkpoint inhibition with monoclonal antibodies (mAbs). CAR T cells have potent activity against pediatric acute lymphoblastic leukemia but have not yet demonstrated activity against solid tumors. Checkpoint inhibition alone (e.g., anti- PD-1 mAb) may not have significant anti-NB activity due to its efficacy correlating with the frequent tumor cell mutations and to the paucity of mutations in NB. Our strategy focuses on cell and mAb based immunotherapies for NB that does not require high-level inherent immunogenicity and builds upon recent advances in our understanding of the tumor cell:immune system interface. We hypothesize that therapeutic gains will be greatest if strategies both enhance cell intrinsic functions of CAR T cells and activated NK (aNK) cells, and overcome cell extrinsic immunosuppression in the tumor microenvironment (TME). Our Specific Aims are to enhance the potency and durability of CAR T cells and aNK cells and to develop regimens that combine enhanced cell therapies with modulation of the immunosuppressive TME. Our Research Strategy/Approach is 1) to enhance the potency and durability of GD2-CARs using targeted mutagenesis of the scFv to prevent antigen-independent tonic signaling and exhaustion originating from the scFv; to test a novel B7-H3-CAR with demonstrated activity; and to add PD-1 blockade to enhance potency and limit exhaustion; 2) to increase trafficking, persistence and potency of aNK cells by combining them with anti-GD2 and anti-B7-H3 mAbs and with a superagonist IL-15; and 3) to overcome immune suppression in the TME with an anti-CD105 mAb to suppress/eliminate mesenchymal stroma and endothelial cells, with a CSF1R inhibitor to eliminate suppressive MDSC and TAMs (collaboration with Project 4), with a TGFBR1 inhibitor to prevent suppression by TGFβ1, and with a FAK/ALK inhibitor to overcome FAK-based induction of T cell suppression and exhaustion (collaboration with Project 1). In summary, novel approaches to enhance the potency and durability of adoptive T cell and NK cell therapies will be developed for translation into clinical trials conducted by Core B (NANT consortium) for patients with high-risk NB.