Anti-angiogenic gene therapy of ocular vascular diseases

项目摘要 新生血管性老年性黄斑变性(NAMD)合并脉络膜新生血管(CNV)是一种主要的 发达国家老年人致盲的原因。所有目前批准用于NAMD的抗血管生成药物， 如雷尼比珠单抗和阿普利赛特，靶向血管内皮生长因子(VEGF)，但有限 治疗效果。对一种抗血管内皮生长因子药物反应差的患者通常会改用另一种血管内皮生长因子药物 由于缺乏针对其他血管生成途径的批准药物而导致的抑制剂。此外，重复 抗血管内皮生长因子耐药患者玻璃体内注射可能增加眼部注射相关风险 并发症。提高疗效的新策略是开发抗血管内皮生长因子非依赖性的新疗法。 用于替代或联合治疗的血管生成因子。避开重复性玻璃体内的另一种策略 注射疗法是开发一种只需一次注射即可长效的抗血管生成基因疗法 功效。然而，目前的抗血管内皮生长因子基因治疗方法对 补充雷尼比珠单抗，可能是因为它们的作用机制相似。为了绕过这些问题， 我们最近发现了一种新的血管生成因子，具有高的疾病选择性和血管内皮生长因子非依赖性 机械装置。我们研制了一种针对该靶点的单抗，并证明了它的高效性。 用于CNV的抗血管生成治疗。本项目的目的是针对这一新的基因疗法开发抗血管生成的药物。 使用腺相关病毒(AAV)载体进行靶向。 在目标1中，我们将生成AAV载体来表达针对新靶点的抗体Fab片段 和血管内皮生长因子在组成性或低氧诱导启动子的指导下进行鉴定表达， Fab片段的体外结合和中和活性。在目标2中，我们将确定治疗效果 以及这些AAV载体在动物模型中缓解CNV的安全性。此外，我们将调查组合 通过在同一小鼠模型中同时靶向这两种因子进行基因治疗，以确定可能的协同作用和 药效提升。该项目的成功实施将带来一种新的抗血管生成基因 治疗将提高CNV的治疗效果并减少每月玻璃体内注射的要求 抗血管内皮生长因子蛋白药物。

Project Summary Neovascular age-related macular degeneration (nAMD) with choroidal neovascularization (CNV) is a leading cause of blindness in the elderly in developed countries. All currently approved anti-angiogenic drugs for nAMD, such as ranibizumab and aflibercept, target vascular endothelial growth factor (VEGF) but have limited therapeutic efficacy. Patients with poor response to one anti-VEGF drug are often switched to another VEGF inhibitors due to the lack of approved drugs against other angiogenic pathways. Furthermore, repeated intravitreal injections in anti-VEGF-resistant patients may increase the risk of injection-related ocular complications. A new strategy is to improve the efficacy is to develop novel therapies against VEGF-independent angiogenic factors for alternative or combination therapy. Another strategy to circumvent repetitive intravitreal injections is to develop anti-angiogenesis gene therapy that requires only a single injection for long-lasting efficacy. However, current approach of anti-VEGF gene therapy yielded marginal treatment benefit to complement ranibizumab, possibly because of their similar mechanisms of action. To circumvent these problems, we recently discovered a novel angiogenic factor with high disease selectivity and VEGF-independent mechanisms. We developed a monoclonal antibody (mAb) against this target and demonstrated its high efficacy for anti-angiogenic therapy of CNV. This project is to develop anti-angiogenesis gene therapy against this novel target using an adeno-associated viral (AAV) vector. In Aim 1, we will generate AAV vectors to express an antibody Fab fragments against the novel target and VEGF under the direction of constitutive or hypoxia-inducible promoters and characterize expression, binding and neutralizing activity of Fab fragments in vitro. In Aim 2, we will determine the therapeutic efficacy and safety of these AAV vectors to alleviate CNV in animal models. Additionally, we will investigate combination gene therapy by simultaneously targeting both factors in the same mouse models to define possible synergy and efficacy improvement. Successful implementation of this project will lead to a novel anti-angiogenesis gene therapy that will improve treatment efficacy of CNV and reduce the requirement for monthly intravitreal injection of anti-VEGF protein drugs.