Development of a Biochemical Diagnosis for Creutzfeldt-Jakob disease

克雅氏病生化诊断的发展

• 批准号: 9199717
• 负责人: RUSSELL M LEBOVITZ
• 金额: $ 125.45万
• 依托单位: AMPRION, INC.
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-15 至 2018-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9199717
• 关键词: Affect; Applications Grants; Area; Asia; Automation; Award; Biochemical; Biological; Biological Assay; Blinded; Blood; Blood Donations; Blood Screening; Blood Transfusion; Blood specimen; Bovine Spongiform Encephalopathy; Brain; Businesses; CJD Variant (V-CJD); Cattle; Cerebrospinal Fluid; Clinical; Consumption; Counseling; Creutzfeldt-Jakob Syndrome; Detection; Development; Diagnosis; Disease; Documentation; Early Diagnosis; Employee; Europe; Evaluation; Freedom; Funding; Future; Genetic Materials; Geographic Locations; Goals; Human; In Vitro; Incidence; Incubated; Individual; Infectious Agent; Institutes; Intellectual Property; Laboratories; Lead; Licensing; Liquid substance; Longitudinal Studies; Marketing; Meat; Medical; Methodology; Names; Nerve Degeneration; Neurodegenerative Disorders; Non-Invasive Cancer Detection; North America; Onset of illness; Organism; Pathway interactions; Patients; Peripheral; Phase; Pilot Projects; Plasma; Population; PrPSc Proteins; Prion Diseases; Prions; Procedures; Process; Proteins; Public Health; Readiness; Regulatory Pathway; Safety; Sampling; Secure; Sensitivity and Specificity; Small Business Technology Transfer Research; Specificity; Spleen; Staging; Surrogate Markers; System; Techniques; Technology; Testing; Time; Tissues; Transplantation; Trust; Tube; United States Food and Drug Administration; Urine; Validation; Variant; Vascular blood supply; Work; authority; base; commercialization; disease diagnosis; nonhuman primate; payment; phase 1 study; preclinical study; programs; protein misfolding cyclic amplification; research study; screening; success

ABSTRACT Human prion diseases are infectious and invariably fatal neurodegenerative diseases, including sporadic Creutzfeldt-Jakob disease (sCJD), the most common form, and variant CJD (vCJD) which is associated to consumption of cattle meat infected by bovine spongiform encephalopathy. Currently there is not sensitive, objective and non-invasive biochemical diagnosis for these diseases, and even less a procedure to detect people incubating the disease in the pre-symptomatic period. This is a major problem for public health, because prion diseases are known to transmit iatrogenically between human-to-human and because due to the long pre- symptomatic stage of the disease—which may span five decades—the asymptomatic carriers far outnumber the clinically affected individuals. To make the situation even more complicated, the infectious agent responsible for these diseases, termed prion, is composed exclusively of a conformationally altered form of a naturally occurring protein, named PrPSc, which has the unique ability to infect individuals and propagate in the body without the need for genetic material. PrPSc is not only the infectious agent and the likely culprit of neurodegeneration, but also the best surrogate marker for the disease. The challenge is that its quantity is high only in the brain at late stages of the disease. However, compelling evidences indicate that PrPSc is present in minute amounts in various peripheral tissues and biological fluids, including blood. This proposal is a continuation of a previously funded phase I/II fast track STTR project (R42NS079060) whose major goal was to develop a blood- and cerebrospinal fluid (CSF)-based detection assay for PrPSc associated with sCJD and vCJD. Our strategy utilizes the protein misfolding cyclic amplification (PMCA) technique, a pioneering proprietary technology developed in Dr Soto's lab. PMCA enables highly efficient prion replication in the test tube by amplification of this process in vitro, and offers a great opportunity to detect very small quantities of prions. During the previous funding cycle we were highly successful to reach the main aims and milestones, including the substantial optimization and improvement of the technology for human samples and the detection of PrPSc in samples of blood and urine of patients affected by vCJD with sensitivity and specificity approaching 100%. Another goal of the phase II was to obtain approval for using PMCA for disease diagnosis. Currently, a variation of the PMCA assay is successfully under use by the USA CJD Surveillance Center based on Cleveland, OH to help the diagnosis of CJD and Amprion is receiving royalty payments for this application. However, given the small number of cases, the diagnosis market is not profitable at this time. Amprion regards the screening of the blood supply as the most relevant market for commercialization of the Company's technology. Based on the success achieved during the phase I and II of this project we engaged in extensive discussions with the UK National Institute for Biological Standards and Control (NIBSC), the governmental organism trusted with the responsibility to validate and approve prion detection techniques in the UK and the Food and Drug Administration (FDA) to define the regulatory pathway to get approval for detection of prions in human blood. As a result of these discussions we have agreed to a validation pathway defined by these agencies to obtain regulatory approval for the commercialization of a PMCA-based assay for detection of prions in human blood samples and started the phase I of this process. The main goal of this Commercialization Readiness Pilot (CRP) project is to complete the regulatory and market approval of our test for detecting prions in blood of people infected by the vCJD agent and to increase the throughput of the assay to handle the number of samples expected during commercialization. The validation pathway includes 4 steps, namely: (i) testing a panel of blood samples spiked with vCJD brain or spleen extracts, (ii) a large screening of negative samples to assess specificity, (iii) a panel of samples from non-human primates infected with the vCJD agent and (iv) a group of samples from patients with confirmed vCJD. These samples will be provided blindly by the NIBSC or the FDA. The results generated in this project would lead to the development of a validated biochemical test to detect vCJD prions in human blood and the demonstration that this can be achieved before the clinical onset of the disease in asymptomatic carriers through the longitudinal studies in non-human primates experimentally infected with the vCJD agent. Availability of a validated methodology to screen blood for infectious prions will increase the safety of blood transfusions and potentially also products derived from human plasma. Finally, such a screening test could be utilized for a study of the size of the asymptomatic population of carriers (i.e. the number of people infected with the vCJD agent who have not yet developed the clinical disease). For commercialization of the validated test, Amprion will establish validated reference laboratories in different geographic locations (e.g. North America, Europe, Asia) that can handle the centralized testing of the samples with the accuracy, efficiency and safety needed for this type of assays.

摘要 人类朊病毒疾病是一种传染性且总是致命的神经退行性疾病，包括散发性疾病 克雅氏病（sCJD）是最常见的形式，变异型CJD（vCJD）与以下疾病相关： 食用感染牛海绵状脑病的牛肉。目前还没有敏感的， 这些疾病的客观和非侵入性的生化诊断，更不用说一个程序来检测 在症状前潜伏期的人。这是公共卫生的一个主要问题，因为 已知朊病毒疾病在人与人之间通过医源性传播， 疾病的症状阶段--可能跨越50年--无症状携带者的数量远远超过 临床影响的人。使情况变得更加复杂的是， 这些疾病称为朊病毒，它完全由天然存在的 蛋白质，命名为PrPSc，具有感染个体并在体内繁殖的独特能力， 需要遗传物质。PrPSc不仅是感染因子和神经变性的可能罪魁祸首， 也是疾病的最佳替代标记。挑战在于，它的数量只在大脑中很高， 疾病的阶段。然而，令人信服的证据表明，PrPSc存在于微量的， 各种外周组织和生物液体，包括血液。 该提案是先前资助的I/II期快速通道STTR项目（R42 NS 079060）的延续， 主要目标是开发一种基于血液和脑脊液（CSF）的PrPSc相关检测方法 sCJD和vCJD。我们的策略利用了蛋白质错误折叠循环扩增（PMCA）技术，这是一种 索托博士实验室开发的开创性专有技术。PMCA使朊病毒在细胞内高效复制成为可能， 试管通过扩增这一过程在体外，并提供了一个很大的机会，以检测非常小的数量 朊病毒在上一个供资周期，我们非常成功地实现了主要目标和里程碑， 包括对人体样本的技术和检测技术的实质性优化和改进， 检测vCJD患者血、尿中PrPSc的敏感性和特异性接近 百分百确定第二阶段的另一个目标是获得批准使用PMCA进行疾病诊断。现时 美国CJD监测中心成功使用了PMCA检测试剂盒的变体， 克利夫兰，俄亥俄州，以帮助诊断CJD和安普里昂是收到版税支付这一应用程序。 然而，鉴于病例数量较少，诊断市场目前并不有利可图。Amprion问候 血液供应的筛选是公司商业化最相关的市场， 技术.基于该项目第一和第二阶段取得的成功，我们进行了广泛的 与英国国家生物标准和控制研究所（NIBSC），政府 在英国和英国，负责验证和批准朊病毒检测技术的生物体 美国食品和药物管理局（FDA）规定了监管途径，以获得批准，检测朊病毒在 人血作为这些讨论的结果，我们已经同意了由以下内容定义的验证途径： 机构获得监管机构批准，将基于PMCA的朊病毒检测方法商业化 并开始了这个过程的第一阶段。 该商业化准备试点（CRP）项目的主要目标是完成监管和市场 批准我们的测试检测朊病毒在血液中的人感染的vCJD代理，并增加 商业化过程中预期处理的样本数量。验证 该途径包括4个步骤，即：（i）检测一组掺有vCJD脑或脾的血液样品 提取物，（ii）阴性样品的大筛选以评估特异性，（iii）来自非人类的一组样品 感染vCJD因子的灵长类动物和（iv）来自确诊vCJD患者的一组样品。这些 样本将由NIBSC或FDA盲法提供。 该项目产生的结果将导致开发一种经过验证的生化检测方法， 人血液中的vCJD朊病毒，并证明这可以在临床发病前实现。 通过对实验感染的非人灵长类动物的纵向研究， vCJD代理人。一个有效的方法来筛选血液中的传染性朊病毒的可用性将增加 输血的安全性，以及潜在的来自人血浆的产品。最后，这样一个 筛查试验可用于研究无症状携带者人群的规模（即 感染vCJD因子但尚未发展为临床疾病的人）。用于商业化 Amprion将在不同的地理位置（例如， 北美、欧洲、亚洲），能够准确、高效地处理样品的集中检测 和安全性。