Phosphorylated Tau 217 (pTau-217) Plasma

Use: This test is used to aid in the biological identification of Alzheimer's disease by measuring phosphorylated tau 217, which has been shown in the literature to be a surrogate of amyloid pathology. Additionally, pTau-217 can be used for monitoring patients on newly approved anti-amyloid therapy.

Clinical cutoff value was established using samples from a well-established patient cohort characterized with amyloid PET data. A pTau-217 value of >0.18 is a reported surrogate marker for beta-amyloid pathology and can be used to facilitate biological identification of Alzheimer's disease.1 pTau-217 has also been used in clinical trials to monitor patients on anti-amyloid therapy.2,3

Limitations: This test is performed by Fujirebio Lumipulse chemiluminescent enzyme immunoassay (CLEIA). Values obtained with different methods cannot be used interchangeably. The validated limit of quantification is 0.06 pg/mL. Assay detection limit is 0.03 pg/mL.

This test was developed and its performance characteristics determined by Labcorp. It has not been cleared or approved by the Food and Drug Administration.

Methodology: Fujirebio Lumipulse chemiluminescent enzyme immunoassay (CLEIA)

Reference Interval
0.00–0.18 pg/mL