Pharmacodynamic Biomarker of Myotonic Dystrophy

强直性肌营养不良的药效生物标志物

基本信息

批准号：
10651049
负责人：
Johanna Hamel
金额：
$ 42.12万
依托单位：
UNIVERSITY OF ROCHESTER
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-08-01 至 2028-05-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10651049
关键词：
Address Affect Affinity Agreement Alternative Splicing Animal Model Ankle Atrophic Biological Assay Biological Markers Biopsy Specimen CUG repeat Cataract Cessation of life Clinical Clinical Trials Defect Degenerative Disorder Detection Development Disease Distal Dose Drug Approval Drug Kinetics Endosomes Evaluation Event Face Frequencies Gene Transduction Agent Genetic Transcription Hand Heart Block Hip region structure Human Individual Inherited Laboratories Link Measurement Messenger RNA Methods Monitor Movement Mus Muscle Muscle Fibers Muscle Weakness Muscle function Myotonia Myotonic Dystrophy Myotonic dystrophy type 1 Needle biopsy procedure New Agents Oligonucleotides Patients Pattern Performance Persons Pharmaceutical Preparations Phase Physiological Procedures Process Program Development Property Protein Isoforms Proteins RNA RNA Splicing RNA-Binding Proteins Regimen Reporting Role Sampling Severity of illness Shoulder Skeletal Muscle Speed Symptoms Testing Therapeutic Therapeutic Intervention Therapeutic Trials Time Toxic effect Transcript Validation biobank biomarker driven clinical examination cohort compare effectiveness deltoid muscle design disability disease heterogeneity drug development early phase trial effective therapy experience gain of function improved indexing interstitial cell motility disorder mouse model novel novel therapeutics pharmacodynamic biomarker pharmacologic population stratification preclinical study premature preservation programs prospective response small molecule tibialis anterior muscle transcriptome sequencing treatment response trial design wasting

项目摘要

ABSTRACT. Myotonic dystrophy type 1 (DM1) and type 2 (DM2) are dominantly-inherited degenerative disorders that cause muscle weakness and multi-systemic symptoms. Both disorders involve RNA toxicity, a novel gain-of-function mechanism, triggered by expression of RNAs that have thousands of CUG- or CCUG- repeats (DM1 or DM2, respectively). Key proteins that regulate RNA alternative splicing, that have high affinity for CUG- and CCUG-repeats, become trapped on repetitive RNA, causing mis-regulated splicing of transcripts encoding critical components of skeletal muscle. In mouse models we have used a variety of approaches, including oligonucleotides, gene therapy vectors, and small molecules, to show that reduction of RNA toxicity causes normalization of RNA splicing and muscle function, suggesting that DM is at least partly reversible. We also reported that targeted RNAseq analysis of misregulated splice events is reliable and sensitive for monitoring therapeutic impact in mice, providing a near-real-time assessment of target engagement. These developments, and prospects for conducting biomarker-driven trials, have spurred many drug development programs for DM, including some that are now advancing to IND-enabling studies or early-phase trials. To prepare for these studies we developed human targeted RNAseq similar to that employed in mouse studies. Building on comprehensive discovery by deep RNAseq of more than 90 muscle samples, we identified transcripts that show splicing dysregulation, and then developed targeted RNAseq to evaluate 22 splice events that show large effects in DM1. We then determined a composite splicing index for each sample. The splicing index stratifies the population in a large cohort of DM1 patients, correlates with the extent of muscle weakness, shows acceptable test-retest agreement of splicing defects over 2-3 months, and provides a serviceable pharmacodynamic biomarker. However, as the field advances and we gain more experience, important limitations have emerged, particularly in the method for obtaining muscle samples and the selection of splice events for targeted RNAseq – two aspects that are closely linked. Here we seek to optimize and show feasibility for a new sampling method, called myoaspiration, that enables multi-sampling. i.e. sampling of more muscles on more occasions. In parallel, we seek to optimize and validate a new targeted RNAseq assay, applicable to both DM1 and DM2, designed to accommodate myoaspirate samples, and providing greater precision and stronger inferences about target engagement in muscle fibers. Performance of the assay will be initially evaluated using previously collected samples in our BioBank, and then proceed to prospective evaluation of newly-collected myoaspirate samples from DM1 and DM2 patients, focusing on the muscles that are selectively affected or relatively spared. Upon completion, the project is expected to provide a simple yet effective pharmacodynamic biomarker for therapeutic trials leading to drug approval, and for post-approval studies to compare the effectiveness of different agents, regimens, and combinations.

摘要：强直性肌营养不良 1 型 (DM1) 和 2 型 (DM2) 是显性遗传的退行性肌营养不良。导致肌肉无力和多系统症状的疾病这两种疾病都涉及 RNA 毒性。新颖的功能获得机制，由具有数千个 CUG- 或 CCUG- 的 RNA 表达触发重复序列（分别为 DM1 或 DM2），是调节 RNA 选择性剪接的关键蛋白，具有高亲和力。对于 CUG 和 CCUG 重复，被重复 RNA 困住，导致转录本的剪接错误调节在小鼠模型中，我们使用了多种方法来编码骨骼肌的关键成分，包括寡核苷酸、基因治疗载体和小分子，以表明 RNA 毒性的降低导致 RNA 剪接和肌肉功能正常化，表明 DM 至少是部分可逆的。还报告说，针对错误调控剪接事件的靶向 RNAseq 分析对于以下情况是可靠且灵敏的：监测小鼠的治疗效果，提供目标参与度的近实时评估。生物标志物驱动试验的发展和前景刺激了许多药物的开发 DM 项目，包括一些目前正在推进 IND 研究或早期试验的项目。为这些研究做准备，我们开发了类似于小鼠研究中使用的人类靶向 RNAseq。基于深度 RNAseq 对 90 多个肌肉样本的全面发现，我们确定了显示剪接失调的转录本，然后开发靶向 RNAseq 来评估 22 个剪接事件然后我们确定了每个样本的复合剪接指数。指数对一大群 DM1 患者进行人群分层，与肌肉无力的程度相关，显示 2-3 个月内可接受的拼接缺陷测试-重测一致性，并提供可用的服务然而，随着该领域的进步和我们获得更多经验，重要的是。已经出现了局限性，特别是在获取肌肉样本的方法和拼接的选择方面靶向 RNAseq 的事件——两个密切相关的方面，我们寻求优化并展示可行性。一种称为“myoaspiration”的新采样方法，可以进行多重采样，即对更多肌肉进行采样。与此同时，我们寻求优化和验证新的靶向 RNAseq 测定，适用于 DM1 和 DM2 均设计用于容纳肌抽吸样本，并提供更高的精度和最初将对该测定的性能进行更强有力的推论。使用我们生物库中之前收集的样本进行评估，然后进行前瞻性评估从 DM1 和 DM2 患者新收集的肌抽吸样本，重点关注选择性的肌肉完成后，该项目预计将提供一个简单而有效的方案。用于导致药物批准的治疗试验以及批准后研究的药效生物标志物比较不同药物、方案和组合的有效性。