Anti-angiogenic gene therapy of ocular vascular diseases

项目摘要 新生血管性年龄相关性黄斑变性（nAMD）伴脉络膜新生血管（CNV）是目前最常见的视网膜病变。 发达国家老年人失明的原因。所有目前批准的用于nAMD的抗血管生成药物， 例如雷珠单抗和阿柏西普，靶向血管内皮生长因子（VEGF），但具有有限 疗效对一种抗VEGF药物反应不佳的患者通常会改用另一种VEGF 由于缺乏针对其他血管生成途径的批准药物，此外，重复 抗VEGF耐药患者的玻璃体内注射可能会增加注射相关性眼部疾病的风险。 并发症提高疗效的一个新策略是开发针对VEGF非依赖性的新疗法。 血管生成因子的替代或联合治疗。另一种避免重复玻璃体内注射的策略 注射是开发抗血管生成基因治疗，只需要一个长期持久的注射 功效然而，目前的抗VEGF基因治疗方法对 补充雷珠单抗，可能是因为它们的作用机制相似。为了避免这些问题， 我们最近发现了一种新的血管生成因子，具有高度的疾病选择性和VEGF非依赖性， 机制等我们开发了针对该靶点的单克隆抗体（mAb），并证明了其高效性 用于CNV的抗血管生成治疗。本项目旨在针对这种新型的抗血管生成基因治疗方法 使用腺相关病毒（AAV）载体靶向。 在目标1中，我们将产生AAV载体以表达针对新靶标的抗体Fab片段 和VEGF在组成型或低氧诱导型启动子的指导下表达并表征表达， 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 这些AAV载体减轻动物模型中CNV的安全性。此外，我们还将研究 通过在相同的小鼠模型中同时靶向两种因子以确定可能的协同作用的基因治疗， 功效改善。该项目的成功实施将导致一种新的抗血管生成基因 将提高CNV治疗效果并减少每月玻璃体内注射需求的疗法 抗血管内皮生长因子蛋白质药物。

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.