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 通过足跟采血棒采集血样 （HL 140662 IIB期SBIR） 抗凝治疗适用于患有先天性心脏病、血栓形成或 有血栓形成的风险在过去的十年里， 儿科患者的抗凝治疗，高达15%的住院儿童接受肝素或 类肝素使用这些疗法需要频繁的实验室检测（每4小时）， 分析物-抗凝血酶功能（ATIII）、因子Xa活性（Xa）和活化部分凝血活酶时间（aPTT） --避免用药不足（血栓形成事件）或用药过量（出血）。肝素治疗的现有诊断 在新生儿和儿童中是有问题的，因为它们通常被标准化用于成人样品， 每种分析物的全血量高达2 mL，或者对于整个样本组，每天的累积血量高达12 mL。 开发低容量、微创和快速周转的诊断测试是一个关键的未满足的需求 用于监测儿童肝素治疗的面板，在单个平台上进行多种分析物检测。 通过本项目（R44 HL 140662）第I和II阶段完成的工作已确定执行 用于抗凝剂（肝素， 类肝素）在我们的近患者数字微流体平台（FINDER）上。该平台最近获得了CE认证 用于葡萄糖-6-磷酸脱氢酶（G6 PD）检测，正在等待FDA的510（k）批准。的 拟议的IIB期项目将支持按照CLSI指南进行全面的分析验证，并进行严格的临床试验。 我们的肝素检测试剂盒获得FDA批准所需的验证。我们正准备进行一场预- 向FDA提交关于我们的验证方案和验证研究设计的申请，以满足510（k） 基于每种分析物的单一测试同品种器械的要求。我们正在与我们的临床 波士顿儿童医院的合作伙伴，以优化肝素检测平台工作流程，实现无缝集成 在商业化后进入医院实验室。 通过这一IIB期机制提供的资金将完成我们FINDER肝素的开发路径 监测平台，从概念到市场，通过预期的FDA批准。目前没有一个单一的 提供即时检测平台，支持ATIII、Xa和aPTT的快速检测。该小体积 我们的数字微流控技术所固有的格式使所有三种测定都能够在不到50 通过足跟穿刺或静脉穿刺采集的100 ml全血或血浆，非常适合儿科使用 频繁抽血会显著增加医源性贫血的风险。通过组合三 将技术复杂的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（缩短样本至应答时间，单份血液中的三种分析物检测结果 样本），并通过减少肝素重复检测所需的血量来改善临床结局 和其他抗凝剂。

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.