Urocortin-2 Gene Transfer for CHF: a Paracrine Approach Using Intravenous AAV8

Urocortin-2 基因转移治疗 CHF：使用静脉注射 AAV8 的旁分泌方法

基本信息

批准号：
8714872
负责人：
H. Kirk Hammond
金额：
$ 24.08万
依托单位：
RENOVA THERAPEUTICS, INC.
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-05-01 至 2015-10-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8714872
关键词：
Animals Biodistribution Blood Circulation Blood Vessels Cardiac Cardiovascular Diseases Chickens Clinical Trials Congestive Heart Failure Corticotropin-Releasing Hormone Dependovirus Development Plans Distant Dose Family Family suidae Figs - dietary Fund Raising Funding Future Gene Transfer Goals Health Heart Heart Diseases Heart failure Hormones Immune response Infusion procedures Injection of therapeutic agent Intramuscular Injections Intravenous Legal patent Length of Stay Licensing Mediating Methods Modeling Morbidity - disease rate Mus Myocardium Office Visits Patients Peptides Pharmacologic Substance Phase Plasma Primates Rattus Regulation Relative (related person)Research Design Rodent Safety Serum Sirolimus Site System Technology Testing Tetanus Helper Peptide Tetracyclines Therapeutic Toxic effect Transgenes Virus adeno-associated viral vector base beta Actin commercialization economic cost expression vector gene therapy heart function hemodynamics improved intravenous injection meetings mortality mouse model paracrine preclinical study promoter receptor therapeutic transgene transgene expression urocortin vector vector biodistribution

项目摘要

DESCRIPTION (provided by applicant): Gene transfer for the treatment of cardiovascular diseases is bedeviled by inability to obtain, safely and easily, sufficient cardiac transgene expression. Current methods of gene transfer for heart disease include intramuscular injection into heart muscle or intracoronary delivery, approaches that are cumbersome to apply. Consequently, we have considered the usefulness of a vector encoding a paracrine-type transgene. In this approach, the transgene acts as a hormone, having cardiac effects after being released to the circulation from a distant site. This approach would circumvent the problem of attaining high yield cardiac gene transfer and enable patients to be treated by a systemic injection during an office visit. Furthermore, the approach proposed would eliminate the need for intravenous delivery of therapeutic peptides and thereby circumvent repeated and prolonged hospital stays, high morbidity, and enormous economic costs. The most suited vector to achieve these goals is the adeno-associated virus type 8 (AAV8), which provides long term and extensive expression after intravenous delivery in rodents, pigs, and primates. Urocortin-2, a recently discovered corticotrophin releasing factor family vasoactive peptide, acts via corticotropin-releasing factor type 2 receptors, which are robustly expressed in the heart and vasculature. Studies in animals and patients with congestive heart failure have shown favorable hemodynamic effects of urocortin-2 peptide infusions, including increased contractile function independent of loading, indicating direct cardiac effects. Urocortin-2 is an ideal selection as a therapeutic transgene in the proposed studies. We have established that intravenous delivery of AAV8 using the chicken beta-actin promoter provides sustained high serum levels of UCn2 and increases function of the normal and failing mouse heart. To develop and refine such an approach we propose to determine, in sequential studies in mice and pigs: a) the optimal system to provide regulated transgene expression to enable fine-tuning of plasma transgene levels, and allow turning expression off and on as needed; and b) the safety and efficacy of urocortin-2 gene transfer using this optimal, paracrine-based approach in a mouse model of CHF. Subsequently, in normal pigs we will determine: a) the minimally effective vector dose required to increase serum urocortin-2; b) biodistribution of the vector and transgene; and c) toxicity. HYPOTHESIS: Intravenous injection of an AAV8 vector with regulated expression of urocortin-2 will, through paracrine-mediated actions, have favorable effects on the failing heart. Aim 1. To determine the optimal regulated expression system to achieve long term and dose-responsive urocortin-2 expression in plasma, with minimal immune response and toxicity Aim 2. To test the optimal AAV8 vector providing regulated expression of urocortin-2 (identified in Aim 1) and determine in mice with and without heart failure: a) plasma levels over 12 months; b) efficacy for increasing function of the failing heart and reducing mortality; c) mechanisms for beneficial effects; and d) biodistribution and toxicity of the vector and transgene Aim 3. To test the optimal AAV vector encoding urocortin-2 (confirmed in Aim 2) in normal pigs to determine: a) plasma levels of urocortin-2; b) biodistribution of the vector and transgene; c) toxicity These mechanistic and proof-of-concept studies are designed to be sufficient in scope to lay the groundwork for future studies to be conducted in a CHF model in pigs and subsequently file an IND to initiate a clinical trial.

描述（由申请人提供）：用于治疗心血管疾病的基因转移因无法安全且容易地获得足够的心脏转基因表达而受到困扰。目前治疗心脏病的基因转移方法包括肌肉注射到心肌或冠状动脉内递送，这些方法应用起来很麻烦。因此，我们考虑了编码旁分泌型转基因的载体的有用性。在这种方法中，转基因充当激素，从远处释放到循环中后具有心脏作用。这种方法将规避获得高产量心脏基因转移的问题，并使患者能够在就诊期间接受全身注射治疗。此外，所提出的方法将消除静脉内输送治疗肽的需要，从而避免重复和长期住院、高发病率和巨大的经济成本。最适合实现这些目标的载体是 8 型腺相关病毒 (AAV8)，它在啮齿动物、猪和灵长类动物中静脉注射后可提供长期和广泛的表达。 Urocortin-2 是最近发现的一种促肾上腺皮质激素释放因子家族血管活性肽，通过促肾上腺皮质激素释放因子 2 型受体发挥作用，该受体在心脏和脉管系统中强烈表达。对动物和充血性心力衰竭患者的研究表明，尿皮质素-2 肽输注具有良好的血流动力学效应，包括独立于负荷的收缩功能的增强，表明对心脏有直接影响。在拟议的研究中，Urocortin-2 是作为治疗性转基因的理想选择。我们已经确定，使用鸡β-肌动蛋白启动子静脉注射AAV8可提供持续的高血清UCn2水平，并增强正常和衰竭小鼠心脏的功能。为了开发和完善这种方法，我们建议在小鼠和猪的连续研究中确定：a）提供受调节转基因表达的最佳系统，以实现血浆转基因水平的微调，并允许根据需要关闭和打开表达； b) 在 CHF 小鼠模型中使用这种基于旁分泌的最佳方法进行 urocortin-2 基因转移的安全性和有效性。随后，我们将在正常猪中确定： a) 增加血清尿皮质素-2 所需的最低有效载体剂量； b) 载体和转基因的生物分布； c) 毒性。假设：静脉注射具有受调节的尿皮质素-2 表达的 AAV8 载体将通过旁分泌介导的作用，对衰竭的心脏产生有利的影响。目标 1. 确定最佳调节表达系统，以在血浆中实现长期且剂量响应的 urocortin-2 表达，同时具有最小的免疫反应和毒性目标 2. 测试提供 urocortin-2 调节表达的最佳 AAV8 载体（在目标 1) 并确定有或没有心力衰竭的小鼠：a) 12 个月内的血浆水平； b) 增强衰竭心脏功能和降低死亡率的功效； c) 产生有益效果的机制； d) 载体和转基因的生物分布和毒性目的 3. 在正常猪中测试编码 urocortin-2（在目的 2 中确认）的最佳 AAV 载体，以确定： a) urocortin-2 的血浆水平； b) 载体和转基因的生物分布； c) 毒性这些机制和概念验证研究的范围足以为未来在猪 CHF 模型中进行的研究奠定基础，并随后提交 IND 以启动临床试验。