Novel assay to monitor Tacrolimus levels at the point of care

总结/摘要 2016年，美国进行了超过33，000例器官移植手术，比过去增加了20% 5年器官移植需要终身免疫抑制以防止移植排斥。 他克莫司是一种大环内酯类抗生素，是最有效的免疫抑制剂之一， 移植受者接受它作为维持免疫抑制的一部分。他克莫司具有狭窄的 治疗窗，亚治疗水平使患者面临排斥风险，超治疗水平 导致中毒。除了显著的药代动力学变异性之外，还估计>25%的患者 不依从免疫抑制剂方案，显著增加移植排斥和失败率 增加了美国医疗体系的财政负担。因为接受移植的人需要一辈子 免疫抑制，任何有助于改善剂量和快速检测非依从性的方法， 具有很大的临床应用价值。 因为他克莫司水平不能在护理点确定，所以在患者中检测非治疗水平是不可能的。 门诊病人的情况很有挑战性患者必须在常规检查之前参加单独的实验室预约 他们可以进行后续访问，或者在访问当天抽取水平。在前者，一个额外的负担是放在 患者参加额外的预约，而后者则排除了在患者的预约之前对水平的分析。 预约药物管理的延迟或患者不依从性的识别使患者处于 移植物排斥风险（亚治疗水平）或药物相关毒性（超治疗水平）。到 为了解决这一技术障碍，Affinergy计划开发一种床旁侧流测定法， 能够频繁、准确和负担得起地监测他克莫司水平。我们已经生成了一个 专利捕获试剂，并鉴定了几种以纳摩尔亲和力结合的候选检测试剂 他克莫司在第一阶段结束时，我们将有一个原型侧流测定与确定的限制， 定量在第二阶段，我们将扩大检测试剂的生产规模，优化性能特征， 储存条件，确定稳定性和使用移植受体血液样本评估我们的测定。 该项目的成功完成将改善接受他克莫司治疗的患者的长期维持治疗 用于免疫抑制，减轻患者和提供者的负担。

SUMMARY/ABSTRACT In 2016, over 33,000 organ transplants were performed in the United States, an increase of 20% over the past 5 years. Organ transplantation requires lifelong immunosuppression to prevent rejection of the transplant. Tacrolimus, a macrolide antibiotic, is one of the most effective immunosuppressants, with >90% of solid organ transplant recipients receiving it as part of their maintenance immunosuppression. Tacrolimus has a narrow therapeutic window, with sub-therapeutic levels putting patients at risk for rejection and supra-therapeutic levels leading to toxicity. In addition to significant pharmacokinetic variability, it is also estimated that >25% of patients are non-adherent to their immunosuppressant regimen, significantly increasing graft rejection and failure rates and increasing the financial burden on the US healthcare system. Because transplant recipients require a lifetime of immunosuppression, any methods that facilitate improved dosing and rapid detection of non-adherence are of great clinical utility. Because tacrolimus levels cannot be ascertained at the point of care, detection of non-therapeutic levels in the outpatient setting is challenging. Patients must either attend a separate lab appointment ahead of their routine follow-up visits or they have levels drawn on the day of their visit. In the former, an extra burden is placed on the patient to attend an additional appointment while the latter precludes analysis of levels prior to the patient’s appointment. Delays in medication management or identification of patient non-compliance place the patient at risk for graft rejection (sub-therapeutic levels) or drug-associated toxicities (supra-therapeutic levels). To address this technical hurdle, Affinergy plans to develop a point-of-care lateral flow assay that will enable frequent, accurate and affordable monitoring of tacrolimus levels. We have already generated a proprietary capture reagent and identified several detection reagent candidates that bind with nanomolar affinity to tacrolimus. At the conclusion of Phase I, we will have a prototype lateral flow assay with established limits of quantitation. In Phase II, we will scale up production of our assay, optimize performance characteristics, establish storage conditions, determine stability and evaluate our assay using transplant recipient blood specimens. Successful completion of this project will lead to improved long-term maintenance of patients receiving tacrolimus for immunosuppression and ease the burden on both patients and providers.