A Novel RNA Therapeutics Platform to Treat Facioscapulohumeral Muscular Dystrophy and other Neuromuscular Disorders

摘要： 在这个Fast Track SBIR应用程序中，miRecule建议开发一个肌肉专用平台(Muscle-NAVTM) 用于治疗遗传性神经肌肉疾病的治疗性寡核苷酸。超过50人继承 包括肌病、肌营养不良和代谢性肌肉疾病在内的神经肌肉疾病 被鉴定为单基因支持，由单基因突变引起。寡核苷酸 治疗学提供了通过专门针对突变疾病来纠正其中许多疾病的可能性- 导致基因。仍然存在的一个主要限制因素是能否提供有效剂量的这些大亲水性 分子进入受影响的肌肉细胞。肌肉-NAV将直接由miRecule的抗体技术组成 与治疗性寡核苷酸结合。该抗体将针对肌肉表达的受体，该受体 结合时通过内吞作用诱导摄取。曾经吞噬了我们的新蛋白质和连接化学 艾滋病在胞体内逃逸到细胞质中。 第三种最常见的遗传性肌肉疾病是面部肩周型肌营养不良症(FSHD) 这是美国的一种孤立症状，约有2万名患者。FSHD是由遗传突变导致的 双同源盒4基因的不适当表达。DUX4基因异常表达严重 对肌肉组织有毒，导致氧化应激和肌肉细胞凋亡，降低肌肉功能。 DUX4是一种转录因子，不能被传统的小分子或生物直接“下药” 治疗学。多项研究表明，反义寡核苷酸(ASO)疗法有可能 直接抑制DUX4，逆转临床前模型中的肌肉病理。然而，一个重大的障碍是 发展是一种有效的交付手段。为了验证我们的肌肉导航平台，我们建议交付我们的 (ASO)靶向DUX4(miRecule候选MC-DX4)治疗FSHD。 在快速通道SBIR的第一阶段，我们将首先发现针对十种受体的新抗体，这些抗体具有选择性 通过噬菌体展示筛选获得肌肉表达(AIM 1)。我们将演示选择性交付和 在体外肌肉细胞中的基因敲除(AIM 2)。然后筛选出五种结合物用于肌肉的特定生物分布， 在FSHD小鼠模型中的有效传递和击倒，以及在小鼠中选择单一铅抗体的安全性 肌肉-NAV结合物(AIM 3)。在Fast Track SBIR的第二阶段，我们将优化纵向扩展、流程 肌肉-NAV和MC-DX4的开发和CMC释放试验(AIM 4)。我们会用这个高质量的代理商 研究非人灵长类动物的PK谱、FSHD小鼠模型中的PK/PD谱，以及 大鼠的MTD/给药范围/TK曲线(AIM 5)。我们还将展示竞争优势和长期- MC-DX4对两种FSHD小鼠模型的远期疗效。这些研究的完成 将创建一个引人注目的数据包，我们将使用该数据包为我们的肌肉营销共同开发和许可交易- NAV平台，并使我们的MC-DX4 IND前会议成为治疗FSHD的有效方法。

Abstract: In this Fast Track SBIR application miRecule proposes to develop a muscle-specific platform (Muscle-NAVTM) for the delivery of therapeutic oligonucleotide to treat inherited neuromuscular disorders. Over 50 inherited neuromuscular disorders including myopathies, muscular dystrophies, and metabolic muscle disorders have been identified with a monogenic underpinning, resulting from mutations in a single gene. Oligonucleotide therapeutics offer the potential to correct many of these disorders by specifically targeting the mutated disease- causing gene. A major limiting factor that remains is the ability to deliver effective doses of these large hydrophilic molecules into affected muscle cells. Muscle-NAV will be composed of miRecule’s antibody technology directly conjugated to a therapeutic oligonucleotide. The antibody will be targeted to a muscle expressed receptor that induces uptake via endocytosis upon binding. Once endocytosed our novel protein and conjugation chemistry aids in endosomal escape to the cytoplasm. The third most common inherited muscle disorder is facioscapulohumeral muscular dystrophy (FSHD) an orphan indication in the US, with about 20,000 patients. FSHD results from inherited mutations that lead to inappropriate expression of the double homeobox 4 (DUX4) gene. The aberrant expression of DUX4 is severely toxic to muscle tissues, resulting in oxidative stress and apoptosis of muscle cells degrading muscle function. DUX4 is a transcription factor and is not directly “druggable” by traditional small molecules or biologic therapeutics. Several studies have displayed that antisense oligonucleotide (ASO) therapy has the potential to directly repress DUX4, reversing muscle pathology in pre-clinical models. However, a significant hurdle for the development is an effective means of delivery. To validate our Muscle-NAV platform we propose to deliver our (ASO) targeting DUX4 (miRecule candidate MC-DX4) for the treatment of FSHD. In phase 1 of the fast track SBIR, we will first discover novel antibodies for ten receptors with selective muscle expression through phage display screening (AIM 1). We will demonstrate selective delivery and knockdown in muscle cells in vitro (AIM 2). Then screen five conjugates for muscle specific biodistribution, effective delivery and knockdown in an FSHD mouse model, and safety in mice to select a single lead antibody conjugate for Muscle-NAV (AIM 3). In phase 2 of the fast track SBIR, we will optimize scale-up, process development, and CMC release tests for Muscle-NAV and MC-DX4 (AIM 4). We will use this high-quality agent to characterize PK profiles in Non-Human Primates (NHPs), PK/PD profiles in a mouse model of FSHD, and MTD/ Dosing Range/TK profiles in rats (AIM 5). We will also demonstrate the competitive advantage and long- term therapeutic efficacy of MC-DX4 in two mouse models of FSHD (AIM 6). The completion of these studies will create a compelling data package we will use to market co-development and licensing deals for our Muscle- NAV platform, and enable our pre-IND meeting for MC-DX4 as an effective treatment for FSHD.