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

• 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
• 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

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是由于无法安全，容易获得足够的心脏转基因表达而无法获得的。当前的心脏病基因转移方法包括肌内注射到心脏肌肉或冠状内递送，这是繁琐的应用方法。因此，我们考虑了编码旁分泌型转基因的向量的有用性。在这种方法中，转基因充当激素，从远处释放到循环后具有心脏影响。这种方法将避免获得高产量心脏基因转移的问题，并使患者在办公室访问期间接受全身注射治疗。此外，提出的方法将消除对治疗性肽静脉输送的需求，从而规避重复和延长住院，高发病率和巨大的经济成本。实现这些目标的最合适的载体是与腺相关的8型病毒（AAV8），该病毒在啮齿动物，猪和灵长类动物的静脉内递送后提供了长期和广泛的表达。泌尿科素-2是最近发现的皮质营养素释放因子家族血管活性肽，它通过皮质激素释放因子2型受体起作用，在心脏和脉管系统中均可强烈表达。在动物和充血性心力衰竭患者中的​​研究表明，尿层素-2肽输注的血液动力学作用良好，包括与负荷无关的收缩功能增加，表明心脏直接影响。在拟议的研究中，尿科素-2是理想的选择作为治疗转基因。我们已经确定，使用鸡β-肌动蛋白启动子静脉注射AAV8提供持续的高血清UCN2水平，并增加了正常和失败的小鼠心脏的功能。为了开发和完善这种方法，我们建议在小鼠和猪的顺序研究中确定：a）提供调节转基因表达以实现血浆转基因水平的微调的最佳系统，并允许根据需要打开表达； b）在CHF的小鼠模型中，使用这种最佳的，基于旁分泌的方法，尿果素-2基因转移的安全性和功效。随后，在正常的猪中，我们将确定：a）增加血清尿素素-2所需的微小有效载体剂量； b）载体和转基因的生物分布；和c）毒性。假设：静脉注射AAV8载体具有调节的尿果素-2表达的静脉注射，将通过旁分线介导的作用对失败的心脏产生有利的影响。目的1。确定在血浆中实现长期和剂量响应性尿层素-2表达的最佳调节表达系统，具有最小的免疫反应和毒性目标2。测试最佳的AAV8载体，可提供尿层素-2的调节表达（在AIM 1中鉴定）并确定具有心力衰竭的小鼠，并没有心脏失败：A）质量失败：A）浆液水平12个月以12个月的水平； b）增加心脏失败和降低死亡率功能的功效； c）有益效果的机制； d）载体和转基因目标的生物分布和毒性3。在正常猪中测试编码泌尿生成素-2的最佳AAV载体（在AIM 2中确认）以确定：a）arocorocortin-2的等离子体水平； b）载体和转基因的生物分布； c）这些机械和概念验证研究的毒性旨在在猪中以CHF模型进行以后的研究奠定基础，并随后提交IND来启动临床试验。