Departments of Ophthalmology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
Departments of Medicine and Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, PA, USA.
Mol Ther. 2018 Feb 7;26(2):542-549. doi: 10.1016/j.ymthe.2017.12.002. Epub 2017 Dec 8.
Sustained suppression of VEGF is needed in many patients with neovascular age-related macular degeneration (NVAMD), and gene transfer of a VEGF-neutralizing protein is a promising approach to achieve it. Initial clinical trials testing this approach have shown encouraging signals, but evidence of robust transgene expression and consistent antiangiogenic and antipermeability activity has been lacking. In this study, we demonstrate expression of an anti-human VEGF antibody fragment (antiVEGFfab) after subretinal injection of AAV8-antiVEGFfab. In transgenic mice expressing human VEGF in retina (rho/VEGF mice), a model of type 3 choroidal neovascularization (NV), eyes injected with ≥1 × 10 gene copies (GC) of AAV8-antiVEGFfab had significantly less mean area of NV than null vector-injected eyes. A dose-dependent response was observed with modest reduction of NV with ≤3 × 10, >50% reduction with ≥1 × 10 GC and almost complete elimination of NV with 3 × 10 or 1 × 10 GC. In Tet/opsin/VEGF mice, in which doxycycline-induced high expression of VEGF leads to severe vascular leakage and exudative retinal detachment (RD), reduction of total RD by 70%-80% occurred with 3 × 10 or 1 × 10 GC of AAV8-antiVEGFfab, an effect that was sustained for at least a month. These data strongly support initiating clinical trials testing subretinal injection of AAV8-antiVEGFfab in patients with NVAMD.
许多新生血管性年龄相关性黄斑变性（NVAMD）患者需要持续抑制 VEGF，而基因转移 VEGF 中和蛋白是实现这一目标的有前途的方法。最初的临床试验测试了这种方法，显示出了令人鼓舞的信号，但缺乏稳健的转基因表达以及一致的抗血管生成和抗渗透活性的证据。在这项研究中，我们证明了抗人 VEGF 抗体片段（antiVEGFfab）在视网膜下注射 AAV8-antiVEGFfab 后表达。在视网膜表达人 VEGF 的转基因小鼠（rho/VEGF 小鼠）中，作为 3 型脉络膜新生血管化（NV）的模型，与空载体注射的眼睛相比，注射≥1×10 基因拷贝（GC）的 AAV8-antiVEGFfab 的眼睛 NV 的平均面积明显较小。观察到剂量依赖性反应，用≤3×10 适度减少 NV，用≥1×10 GC 减少>50%，用 3×10 或 1×10 GC 几乎完全消除 NV。在 Tet/opsin/VEGF 小鼠中，强力霉素诱导的 VEGF 高表达导致严重的血管渗漏和渗出性视网膜脱离（RD），用 3×10 或 1×10 GC 的 AAV8-antiVEGFfab 可减少总 RD 70%-80%，效果至少持续一个月。这些数据强烈支持启动临床试验，测试 NVAMD 患者的视网膜下注射 AAV8-antiVEGFfab。
