Multi-receptor Targeting of Glioblastoma

胶质母细胞瘤（GBM）的治疗代表了医学上未满足的需求。我们一直在寻找 使用对流增强递送递送有效的靶向和特异性细胞毒素的治疗方法 （CED）。我们和其他人发现GBM患者过度表达白细胞介素13受体α 2（IL-13 RA 2）， EphA 2、EphA 3和EphB 2受体。这些受体存在于不同的病理生理区室 GBM和所有四种都在肿瘤核心的肿瘤细胞和局部浸润的肿瘤细胞中表达， EphA 2也存在于肿瘤新生血管中。此外，IL-13 RA 2、EphA 2和EphA 3与以下相关，并且 在神经胶质瘤干细胞样细胞（GSC）的病理生物学中起关键作用。最后，EphA 3受体可以是 在M2肿瘤相关巨噬细胞（TMA）中容易检测到。因此，IL-13 RA 2、EphA 2、EphA 3 和EphB 2在显示参与肿瘤进展的主要GBM区室中过表达 和/或对治疗的抗性。Eph受体配体之一ephrinA 5（eA 5）结合EphA 2、EphA 3和EphA 4。 EphB 2受体。在目前的项目中，我们将追求用一种靶向所有四种受体的新想法。 使用监测的和有效的CED递送药物化合物。我们已经设计了一个 基于eA 5和IL-13突变体的试剂，使用IgG 1支架靶向所有四种受体，并将其缀合至 修饰细菌毒素以形成QUAD 3.0-PE 38 QQR。该缀合物在GBM肿瘤中是安全有效的。我们 将通过三个具体目标继续这一令人兴奋的研究路线。在具体目标1中，我们将评估 QUAD 3.0-PE 38 QQR治疗犬高级别胶质瘤的分布、安全性和抗肿瘤活性， 代表了最接近人类疾病的模型。在具体目标2中，我们将开发QUAD 3.0-PE 38 QQR， 在复发性GBM患者中进行的首次人体I期临床试验。我们将使QUAD 3.0-PE 38 QQR下 良好生产规范（GMP）条件。QUAD-CTX将进行临床前动物研究， 基于与FDA的IND前讨论。研究将按照药物非临床研究质量管理规范（GLP）进行 申请新药研究申请（IND）。在第三个具体目标中，我们将执行 QUAD 3.0-PE 38 QQR在复发性GBM患者中的I期临床试验。重点将是获得 CED给药药物的最佳分布容积、其安全性、初始疗效和诱导证据 免疫反应。因此，用一种治疗剂和改进的递送系统，我们将 清除肿瘤细胞和促进其生长的肿瘤微环境的异常细胞。这 这种方法还解决了肿瘤间和肿瘤内异质性的关键问题， 原位接种或所谓的“肿瘤发炎”效应。我们设想这场被我们称为 “分子切除”将使GBM的治疗更加有效。

Treatment of glioblastoma (GBM) represents an unmet need in medicine. We have been pursuing a therapeutic approach of delivering potent targeted and specific cytotoxins using convection-enhanced delivery (CED). We and others found that patients with GBM over-express interleukin 13 receptor alpha 2 (IL-13RA2), EphA2, EphA3 and EphB2 receptors. These receptors are present in various pathophysiological compartments of GBM and all four are expressed in tumor cells of the core of tumor and in locally-infiltrating tumor cells, while EphA2 is also found in tumor neovasculature. Further, IL-13RA2, EphA2, and EphA3 are associated with, and play crucial roles in, the pathobiology of glioma stem-like cells (GSC). Finally, the EphA3 receptor can be readily detected in M2 tumor-associated macrophages (TMA). Thus, collectively, IL-13RA2, EphA2, EphA3 and EphB2 are over-expressed in principal GBM compartments shown to be involved in tumor progression and/or resistance to therapies. One of the Eph receptor ligands, ephrinA5 (eA5), binds EphA2, EphA3 and EphB2 receptors. In the current project, we will pursue the novel idea of targeting all four receptors with one pharmaceutical compound delivered using monitored and effective CED. We have already engineered an agent based on eA5 and IL-13 mutants targeting all four receptors using an IgG1 scaffold and conjugated it to a modified bacterial toxin to form QUAD 3.0-PE38QQR. The conjugate is safe and effective in GBM tumors. We will continue this exciting line of research through three Specific Aims. In Specific Aim 1, we will evaluate QUAD 3.0-PE38QQR distribution, safety and anti-tumor activity in treating canine high-grade gliomas, which represents the closest model of human disease. In Specific Aim 2, we will develop QUAD 3.0-PE38QQR for first-in-human Phase I clinical trial in patients with recurrent GBM. We will make QUAD 3.0-PE38QQR under Good Manufacturing Practices (GMP) conditions. The QUAD-CTX will undergo pre-clinical animal studies, based on pre-IND discussions with the FDA. Studies will be performed under Good Laboratory Practices (GLP) conditions in order to obtain an Investigational New Drug (IND). In the third Specific Aim, we will perform Phase I clinical trial with QUAD 3.0-PE38QQR in patients with recurrent GBM. The focus will be on obtaining optimal volume of distribution of the CED-administered drug, its safety, initial efficacy and evidence of inducing immune responses. Thus, with one therapeutic agent and improved delivery system, we will be eliminating tumor cells and abnormal cells of the tumor microenvironment promoting its growth. This approach also addresses crucial issues of inter- and intra-tumoral heterogeneity and is also expected to evoke an in situ vaccination or so called “tumor inflaming” effect. We envision that this all-out assault, termed by us “molecular resection”, will result in a more effective management of GBM.