Dystrophin Restoration

目前，原理验证研究已经证实，基因替代疗法代表着一种很有前途的 杜氏肌营养不良症(DMD)的治疗方法。我们已经在临床I期取得进展 肌肉注射rAAV-mini-dystrophin基因对该病的安全性基因治疗试验。它是 整个领域都承认，血管输送，到达许多肌肉群，是我们最大的希望 改善患者功能。在与FDA为U54做准备的初步讨论中，我们 鼓励通过循环进行基因传递，注意潜在的安全性 担忧。我们目前的项目考虑到了这些因素。我们在初步调查中发现 研究表明，rAAVS可以有效地将微肌营养不良蛋白输送到mdx小鼠的肌肉中。此外，我们还拥有 数据预测，这种AAV血清型可以跨越物种界限，将转基因传递到 动物物种。这为我们目前的提案奠定了基础，将安全性和有效性问题整合在一起 血管输送。我们计划将其引入IND，并进行血管分娩的I期安全性试验，具体如下： 这个项目(AIM1)的第一个目标是建立我们设计的微肌营养不良蛋白转基因 (根据文献中的最佳信息)可以从功能上改善营养不良的肌肉。为我们的 目前，我们在MDX小鼠身上使用了一块分离的肌肉来证明功能有效性，我们将遵循这一点 此提案中的示例。对于我们的第二个目标(目标2)，我们将把rAAV.microdystrophin交付给 恒河猴。关于AAV和AAV的免疫原性，人们提出了许多问题 它运载的货物。恒河猴允许我们在这样一个环境中解决所有这些问题 近距离模拟临床试验。两个问题迫在眉睫，病毒的安全通过实现转导 以及对患者的安全性，避免病毒的不良传播。因此，我们将提供我们的病毒构建 通过放置在股动脉的气囊导管。我们还将测试 使用一些对AAV和AAV具有预先存在免疫力的猴子进行基因传递的免疫抑制方案 其他人则不会感染病毒。在最终的目标3中，我们将按照以下规定进行毒理学/生物分布研究 我们与FDA的讨论。从这个项目获得的信息将允许我们提交IND申请 DMD男孩的I期安全性试验。

Currently, proof-of-principle studies have established that gene replacement therapy represents a promising means of treatment for Duchenne muscular dystrophy (DMD). We have moved forward in a clinical phase I safety gene therapy trial for this disease by intramuscular delivery of an rAAV mini-dystrophin gene. It is acknowledged throughout the field that vascular delivery, reaching many muscle groups, is our best hope for improving patient function. In preliminary discussions with the FDA in preparation for this U54, we were encouraged to move forward with gene delivery through the circulation, being mindful of potential safety concerns. Our current project takes these considerations into account. We have found in preliminary studies that rAAVS can deliver micro-dystrophin efficiently to muscle in the mdx mouse. Further, we have data that predicts that this AAV serotype can cross species lines with delivery of a transgene to a large animal species. This sets the stage for our current proposal, integrating safety and efficacy concerns of vascular delivery. Our plan to bring this to IND and a phase I safety trial for vascular delivery is as follows: The first goal for this project (AIM1) is to establish that the micro-dystrophin transgene that we designed (based on the best information from the literature) can functionally improve dystrophic muscle. For our current IND we used an isolated muscle in the mdx mouse to prove functional efficacy and we will follow this example in this proposal. For our second goal (AIM 2) we will deliver the rAAVS.micro-dystrophin to the rhesus macaque. There have been many issues raised regarding the immunogenicity of both AAV and the cargo it carries. The rhesus macaque permits us to address all of these issues in an environment that closely simulates a clinical trial. Two concerns are at hand, safe passage of virus to achieve transduction and safety to the patient avoiding undesirable spread of virus. Thus, we will deliver our viral construct through a balloon catheter placed in the femoral artery. We will also test appropriateness of immunosuppression regimens for gene delivery using some monkeys with pre-existing immunity to AAV and others naTve to the virus. In the final AIM 3, we will do the toxicology/biodistribution studies in accordance with our discussions with FDA. The information derived from this project will permit us to submit an IND for a phase I safety trial in DMD boys.