Develop AAV9 gene replacement therapy for treating MPS I

项目摘要 NeuroGT，Inc是一家由基因治疗副教授傅海燕博士创立的初创公司 中心位于查佩尔山的北卡罗来纳州大学，其使命是开发和商业化有效的 基因治疗产品来治疗人类罕见的神经遗传性疾病。该项目的目标是开发一个 有效的基因治疗产品针对治疗的根本原因， 粘多糖样沉积症（MPS）I是一种致死性的溶酶体储存病（LSD），由常染色体隐性遗传引起。 α-L-艾杜糖醛酸酶（IDUA）缺陷。重度MPS I（MPS IH，Hurler综合征）代表了大多数 已知病例，通常在10岁之前过早死亡，主要是由于神经系统疾病 恶化和心肺衰竭。没有有效的治疗方法可用于神经适应症， MPS IH。由于全身弥漫性神经病变和血脑屏障（BBB），MPS IH不适用 重组酶替代疗法或骨髓移植，这是标准的 治疗MPS I的躯体症状。针对根本原因的基因替代疗法一直是 被证明是治疗单基因疾病的理想策略。许多研究已经证明 成功地IV或鞘内（IT）递送trans-BBB-亲神经性AAV 9用于治疗神经遗传性疾病。 重要的是，IV和IT rAAV 9递送的功效和安全性特征已被证明是高度有效的。 在不同的神经遗传性疾病（包括LSD）中可重复。 为了获得最佳的治疗潜力，我们已经开发了一种新型的自身互补（sc）AAV载体scAAV。 mCMV-hIDUAop，以递送具有密码子优化的小型化的人IDUA cDNA。当在体外试验时， 在人MPS IH细胞中，该scAAV-hIDUAop载体构建体显示以约100 μ g/ml的浓度表达功能性IDUA蛋白。 水平比单链（ss）rAAV-hIDUAop载体高8倍。重要的是， scAAV-hIDUAop载体也导致rIDUA分泌增加11倍，其可以进入非- 清除MPS I细胞并清除其中的GAG储存。我们的初步数据有力地支持了 进一步发展为人类临床应用。在这个拟议的项目中，为了临床相关性，我们 将使用AAV 9通过IV、鞘内（IT）和IV+IT在MPS I小鼠模型中测试这种新的scAAV-hIDUAop载体 递送，以评估治疗潜力并确定治疗MPS I的最佳方案。的 拟议的项目将使我们能够生成严格的临床前疗效和安全性数据，以支持 随后的临床开发和商业化。

Project Summary NeuroGT, Inc is a start-up company founded by Dr. Haiyan Fu, an associate professor in the Gene Therapy Center at University of North Carolina at Chapel Hill, with the mission of develop and commercialize effective gene therapy products to treat rare neurogenetic diseases in humans. The goal of this project is to develop an effective gene therapy product targeting the root cause for treating Mucopolysaccharidosis (MPS) I is a fatal lysosomal storage disease (LSD) caused by autosomal recessive defects in α-L-iduronidase (IDUA). Severe form of MPS I (MPS IH, Hurler syndrome) represents the majority of known cases, with premature deaths usually before age 10 years, predominantly due to neurological deterioration and cardiorespiratory failure. No effective treatment is available for neurological indications of MPS IH. Because of the global diffuse neuropathy and the blood brain barrier (BBB), MPS IH is not amenable to either recombinant enzyme replacement therapy or bone marrow transplantation, which are the standard of care for treating somatic symptoms of MPS I. Gene replacement therapy targeting the root cause has been demonstrated to be an ideal strategy for treating monogenic diseases. Numerous studies have demonstrated successful in IV or intrathecal (IT) delivery of trans-BBB-neurotropic AAV9 for treating neurogenetic diseases. Importantly, the efficacy and safety profiles of IV and IT rAAV9 delivery have been demonstrated to be highly reproducible across different neurogenetic diseases, including LSDs. For optimal therapeutic potential, we have developed a novel self-complementary (sc) AAV vector, scAAV- mCMV-∆hIDUAop, to deliver a miniaturized human IDUA cDNA with codon-optimization. When tested in vitro in human MPS IH cells, this scAAV-∆hIDUAop vector construct was shown to express functional IDUA protein at a level 8-fold higher, than the single-stranded (ss) rAAV-hIDUAop vector. Importantly, the transduction with scAAV--∆hIDUAop vector also lead to 11-fold increase in the secretion of rIDUA, which can enter non- transduce MPS I cells and clear GAG storage there. Our preliminary data strongly support the potential of further development towards clinical application in humans. In this proposed project, for clinical relevance, we will test this new scAAV-∆hIDUAop vector in MPS I mouse model using AAV9, via IV, intrathecal (IT) and IV+IT delivery, to assess the therapeutic potential and determine the optimal regimen for treating MPS I. The proposed project will allow us to generate rigorous preclinical efficacy and safety data, to support the subsequent clinical development and commercialization.