Novel diagnostic and safety biomarkers of liver injury and hepatotoxicity

描述(由申请人提供)：各种形式的肝损伤导致的肝损伤和衰竭是美国和世界范围内总体发病率和死亡率的重要来源。病毒性肝炎、脂肪性肝病(脂肪性肝炎)、药物或酒精以及自身免疫性肝炎都会造成持续性肝损伤。肝损伤是由复杂创伤引起的多器官衰竭的重要组成部分，包括冲击伤、感染性休克和肝移植后移植失败，这些情况往往会导致患者死亡。血清丙氨酸氨基转移酶和天冬氨酸氨基转移酶被广泛用作肝功能检查的一部分，对肝脏既不敏感，也不特异，也不能评估肝脏损伤的程度或预测结果。如果肝损伤迫在眉睫，组织活检通常用于诊断。这表明临床上明确需要非侵入性生物标志物来早期检测肝损伤，并提供更好的诊断信息。我们建议继续开发新的肝脏特异性生物标志物，这些生物标志物很容易在血清中检测到，可以用于肝损伤患者的早期诊断，并有助于在药物治疗期间监测患者潜在的肝脏毒性。我们的生物标记物也可用于肝毒性的临床前研究。我们在大鼠肝损伤模型中发现了几个新的肝脏特异性生物标志物，其中精氨酸琥珀酸合成酶(ASS)和肝脏雌激素磺基转移酶(EST-1)是最敏感的标志物，它们在血液中迅速积聚，并与损伤的严重程度相关。在第一阶段，建立了血清ASS定量的原型软件，并获得了足够的数据，证明了与ALT/AST相比，在肝损伤的实验模型中，生物标记物具有更高的敏感性和特异性。此外，我们还提供了概念验证数据，表明血清ASS在人类几种类型的肝病和肝损伤患者中的诊断和预后价值。在第二阶段，将开发一种适用于ASS和EST-1的即用型ELISAs试剂盒，并在大鼠肝损伤和肝毒性模型的临床前研究中进行验证。在有质量保证的条件下，将生产足够的化验组件(例如抗体和抗原)。我们将表征ASS和EST-1检测在人类各种类型的肝病和肝损伤患者中的诊断潜力。生物标志物水平将与包括肝脏活检、血清学和实验室数据在内的临床数据相关联，重点是肝脏损伤严重程度、疾病进展和预后。将评估ASS/EST-1的准确性、敏感性、特异性和诊断/预后价值，并与ALT/AST进行比较。这些分析将用于支持向FDA提交IDE前应用程序，以验证这些分析作为诊断工具并进一步商业化。这一第二阶段项目的成果将是两个肝脏损伤生物标志物的质量保证的ELISA分析，以及支持使用这些生物标志物作为辅助诊断肝脏损伤的工具的临床数据，并监测远远超出ALT/AST测量信息的肝脏毒性的程度。 公共卫生相关性：肝脏健康是人类福祉的一个主要组成部分。许多环境化学物质、病原体、药物或过量酒精都会损害肝脏并影响其功能。据估计，有550万美国人患有慢性肝病，包括病毒性肝炎、酒精性肝病或肝癌，这些疾病经常导致肝功能衰竭，需要肝移植。此外，越来越多的处方药，如降胆固醇药物和非处方药，包括对乙酰氨基酚，可能会导致肝脏毒性，因此需要进行肝功能检查。在过去的30年里，血清ALT和AST两种酶一直被用于肝功能检查以评估肝脏健康状况。然而，ALT/AST在发现轻微损伤、评估损伤程度或预测结果方面既不敏感，也不特异。Banyan Biomarkers正在开发预测性生物分析方法，如ASS和EST-1，这些方法可以帮助确定因治疗药物或环境毒素而出现肝脏毒性的患者的早期肝脏损害。这些检测将提供一种新的诊断/预后工具，并作为“安全生物标记物”。根据FDA的说法。

DESCRIPTION (provided by applicant): Liver damage and failure due to various forms of hepatic injury is a significant source of overall morbidity and mortality in the US and worldwide. Persistent hepatic injury occurs during viral hepatitis, fatty liver disease (steatohepatitis), drug or alcohol and autoimmune induced hepatitis. Clinical conditions are numerous where hepatic injury is a vital component of multi-organ failure caused by complex trauma including blast injury, septic shock, and graft failure after liver transplantation often leading to death of the patient. Enzymatic assays of serum ALT and AST, widely used as part of a `hepatic function' panel, are neither sensitive nor particularity specific to the liver and do not assess the magnitude of liver injury or predict outcome. If liver damage is imminent, tissue biopsies are routinely used for diagnosis. This indicates an explicit clinical need for non-invasive biomarkers for early detection of liver injury with enhanced diagnostic information. We propose here the continuation of the development of novel liver specific biomarkers which are easily detected in serum and can be used for early diagnosis of patients with liver injury and aid in monitoring of potential liver toxicity in patients during drug treatment. Our biomarkers can also be used in preclinical studies of hepatotoxicity. We identified several novel liver-specific biomarkers in rat models of hepatic injury with the argininosuccinate synthase (ASS) and hepatic estrogen sulfotransferases (EST-1) being the most sensitive markers which rapidly accumulated in blood and correlated with the severity of damage. In Phase I, a prototype SW ELISA for quantifying ASS in serum was developed, and sufficient data were obtained demonstrating the greater biomarker sensitivity and specificity in experimental models of liver injury compared to ALT/AST. Also, we provided the proof-of-concept data indicating the diagnostic and prognostic value of serum ASS in human patients with several types of liver diseases and hepatic injury. In Phase II, a ready-to-use ELISAs Kits for ASS and EST-1 will be developed and validated in preclinical studies in rat models of liver injury and hepatotoxicity. Sufficient supplies of the assay components (e.g. antibodies and antigens) will be produced under quality assured conditions. We will characterize the diagnostic potential of ASS and EST-1 assays in human patients with various types of liver diseases and hepatic injury. The biomarker levels will be that will be correlated with clinical data including liver biopsy, serological and laboratory data with an emphasis on hepatic injury severity, disease progression and outcome. The accuracy, sensitivity, specificity and diagnostic/prognostic values of ASS/EST-1 will be assessed and compared with ALT/AST. These analyses will be used to support a pre-IDE application to the FDA for validation of these assays as diagnostic tools and further commercialization. The deliverables of this Phase II project will be quality assured ELISA assays for two liver injury biomarkers, and clinical data supporting the use of the biomarkers as tools for aid in the diagnosis of liver injury and monitor the magnitude of liver toxicity far beyond information obtained from ALT/AST measurements. PUBLIC HEALTH RELEVANCE: Liver health is a major component of human wellbeing. Many environmental chemicals, pathogens, drugs or excessive alcohol can harm the liver and affect its function. An estimated 5.5 million Americans have chronic liver diseases, including viral hepatitis, alcoholic liver disease or hepatic cancer, which frequently lead to liver failure and requires liver transplantation. Moreover, increasing numbers of prescription drugs such as cholesterol-lowering drugs and over-the-counter medications, including acetaminophen, can potentially cause liver toxicity and, thereby, require medical liver function checks. For the last 30 years, two enzymes, serum ALT and AST have been used in hepatic function panels to assess liver health. However, ALT/AST are neither sensitive nor specific to detect mild injure, assess magnitude of damage or predict outcome. Banyan Biomarkers is developing predictive bioassays such as ASS and EST-1 that can help determine liver insults early on in patients that suffer from liver toxicity from therapeutic drugs or environmental toxins. These assays will provide a novel diagnostic/prognostic tools and serve as "safety biomarkers." according to the FDA.