Hodsdon Michael E, Abel Adam, Chambers Antonio, Lu Ming, Morris Amanda, Pontecorvo Michael J, Reiske Heinz, Burnham Samantha C, Collins Emily C, Mintun Mark, Schade Andrew, Beck Rose C
Eli Lilly and Company Indianapolis Indiana USA.
Alzheimers Dement (Amst). 2025 Jun 29;17(3):e70139. doi: 10.1002/dad2.70139. eCollection 2025 Jul-Sep.
Plasma phosphorylated tau217 (p-tau217) is a biomarker for the detection of amyloid pathology. We present performance characteristics of the Lilly SP-X P-tau217 assay in a clinical validation cohort, as a whole and divided into subpopulations from traditionally underrepresented groups.
We measured p-tau217 levels in plasma samples from participants with mild cognitive impairment. Assay performance in predicting positivity for amyloid beta (Aβ) positron emission tomography was examined using two numerical cutoffs.
Two p-tau217 cutoffs were determined with an upper-level group with 95% positive predictive value for Aβ positivity and a lower-level group with 84% negative predictive value for Aβ negativity, with 91% sensitivity and 90% specificity. The remaining indeterminate group represented 18% of participant samples. Similar performance was observed across validation subgroups.
The validation data support the potential clinical utility of the SP-X p-tau217 assay in multiple subpopulations to aid in Alzheimer's disease diagnosis.
The Lilly SP-X p-tau217 assay showed strong concordance with amyloid PET in total cohort and underrepresented groups.Assay performance is in line with guidance from the Global CEOi on AD Working Group.Data support the clinical utility of the assay in multiple cohorts to aid in AD diagnosis.
血浆磷酸化tau217（p-tau217）是检测淀粉样蛋白病理的生物标志物。我们展示了礼来公司SP-X P-tau217检测方法在一个临床验证队列中的性能特征，该队列作为一个整体，并分为传统上代表性不足的亚组。
我们测量了轻度认知障碍参与者血浆样本中的p-tau217水平。使用两个数值临界值检查了该检测方法在预测淀粉样蛋白β（Aβ）正电子发射断层扫描阳性方面的性能。
确定了两个p-tau217临界值，一个较高水平组对Aβ阳性具有95%的阳性预测值，一个较低水平组对Aβ阴性具有84%的阴性预测值，敏感性为91%，特异性为90%。其余不确定组占参与者样本的18%。在验证亚组中观察到了类似的性能。
验证数据支持SP-X p-tau217检测方法在多个亚组中对阿尔茨海默病诊断的潜在临床效用。
礼来公司的SP-X p-tau217检测方法在总队列和代表性不足的组中与淀粉样蛋白PET显示出很强的一致性。检测性能符合全球阿尔茨海默病影像倡议（Global CEOi）AD工作组的指导意见。数据支持该检测方法在多个队列中对AD诊断的临床效用。
