Improving Anticoagulation Monitoring in Pediatric Patients: Use of a Microfluidic Platform to Test Low Volume Blood Samples Obtained by Heel-Stick Collection

摘要 改善儿科患者的抗凝监测：使用微流控平台测试低容量 高跟棒采集法采集的血样 (HL140662阶段IIB SBIR) 抗凝治疗适用于患有先天性心脏缺陷、血栓形成或 都有发展成血栓的风险。在过去的十年里，有一个戏剧性的增长，使用 儿科患者的抗凝治疗，高达15%的住院儿童接受肝素或 类肝素。这些疗法的使用需要频繁的实验室测试(每4小时) 分析物--抗凝血酶功能(ATIII)、Xa因子活性(Xa)和活化部分凝血活酶时间(APTT) --避免服药不足(血栓事件)或服药过量(出血)。肝素治疗的现有诊断方法 在新生儿和儿童中是有问题的，因为它们通常是成人样本的标准化，并要求 每个分析物的全血高达2毫升，或整个仪表板的累积血量高达每天12毫升。 开发一种低容量、微创和快速周转的诊断测试是一个关键的未得到满足的需求 用于监测儿童肝素治疗的面板，其特点是在单一平台上进行多个分析物测试。 通过本项目第一阶段和第二阶段(R44HL140662)完成的工作已经确定了执行 三种关键检测方法(ATIII、Xa和aPTT)用于抗凝剂(肝素、 肝素)在我们的近患者数字微流控平台(Finder)上。该平台最近获得了CE标志 用于葡萄糖-6-磷酸脱氢酶(G6PD)测试，正在等待FDA的510(K)批准。这个 拟议的IIB阶段项目将支持CLSI指南的全面分析验证和严格的临床 我们的肝素化验小组获得FDA批准所需的验证。我们正准备进行一场预赛 向FDA提交关于我们的验证方案和验证研究设计以满足510(K) 基于每个分析物的单一测试判定装置的要求。我们正在与我们的临床医生密切合作 波士顿儿童医院合作伙伴优化肝素检测平台工作流程，实现无缝集成 在商业化的情况下进入医院实验室。 通过这一IIB阶段机制提供的资金将完成我们发现者肝素的发展道路 监测平台，从概念到市场，通过预期的FDA批准。目前没有单一的 提供支持ATIII、Xa和aPTT快速测试的护理点测试平台。小体积 我们的数字微流控技术固有的格式使所有三种分析都可以在不到50分钟的时间内完成 L全血或血浆，通过鞋跟棒或静脉穿刺法采集，非常适合用于儿科 频繁抽血的环境极大地增加了医源性贫血的风险。通过将三个 将复杂的技术分析整合到单一的自动化平台中，我们可以提高 肝素监测分析(缩短了样本到答案的时间，一次血液的三个分析物测试结果 样本)，并通过减少肝素反复检测所需的血量来改善临床结果 和其他抗凝血剂。

ABSTRACT Improving Anticoagulation Monitoring in Pediatric Patients: Use of a Microfluidic Platform to Test Low Volume Blood Samples Obtained by Heel-Stick Collection (HL140662 Phase IIB SBIR) Anticoagulation therapy is indicated for children who suffer from congenital heart defects, thrombosis, or who are at risk of developing thrombosis. Over the past decade, there has been a dramatic increase in the use of anticoagulation therapies in pediatric patients, with up to 15% of hospitalized children receiving heparin or heparinoids. The use of these therapies necessitates frequent laboratory testing (every 4 hours) of multiple analytes -- anti-thrombin function (ATIII), Factor Xa activity (Xa), and activated partial thromboplastin time (aPTT) -- to avoid underdosing (thrombotic events) or overdosing (bleeding). Existing diagnostics for heparin therapy are problematic in newborns and children as they are generally standardized for adult samples and require as much as 2 mL of whole blood per analyte or a cumulative blood volume of up to 12 mL per day for the full panel. There is a critical unmet need to develop a low-volume, minimally invasive, and rapid turn-around diagnostic test panel for monitoring heparin therapy in children that features multiple analyte testing on a single platform. Work completed through Phase I and II of this project (R44HL140662) has established feasibility to perform a panel of three critical assays (ATIII, Xa, and aPTT) for laboratory quality monitoring of anticoagulants (heparin, heparinoids) on our near patient digital microfluidic platform (FINDER). This platform was recently CE marked for glucose-6-phosphate dehydrogenase (G6PD) testing and is pending 510(k) clearance from the FDA. The proposed Phase IIB project will support full analytical validation per CLSI guidelines and a rigorous clinical validation necessary to obtain FDA clearance for our heparin assay panel. We are preparing to engage in a pre- submission with the FDA regarding our validation protocols and design of the validation studies to meet 510(k) requirements based on single test predicate devices for each analyte. We are working closely with our clinical partners at Boston Children’s Hospital to optimize the heparin testing platform workflow for seamless integration into a hospital laboratory setting upon commercialization. Funding through this Phase IIB mechanism will complete the developmental path for our FINDER heparin monitoring platform, from concept to market through anticipated FDA clearance. There is currently no single point-of-care testing platform available that supports rapid testing of ATIII, Xa, and aPTT. The small volume format inherent to our digital microfluidic technology enables all three assays to be performed with less than 50 L of whole blood or plasma, collected via heel-stick or venipuncture, and is perfectly suited for use in pediatric settings where frequent blood draws significantly increase the risk of iatrogenic anemia. By combining three technically complex assays into a single, automated platform, we can improve both technical performance of heparin monitoring assays (reduced sample-to-answer time, three analyte test results from a single blood sample) and improve clinical outcomes through reduced blood volume needed for recurrent testing of heparin and other anticoagulants.