Posdinemab  (Synonyms: JNJ-63733657)

Posdinemab (JNJ-63733657) is a humanized IgG1/κ monoclonal antibody that selectively targets phosphorylated tau (pT217). Posdinemab specifically binds to the pT217+tau epitope rich in the proline domain, blocks tau protein aggregation and seed propagation, and promotes the clearance of extracellular tau species. Posdinemab reduces the levels of free and total p217+tau in cerebrospinal fluid, thereby inhibiting the pathological propagation of tau protein and the formation of neurofibrillary tangles. Posdinemab can be used for the study of progressive supranuclear palsy syndrome and Alzheimer's disease (AD), especially for prodromal or mild AD disease^[1][2][3].

Human IgG1 kappa

Human IgG1 kappa, Isotype Control

MAPT

Artificial cerebrospinal fluid and mouse brain homogenate experiments^[2]:
Posdinemab (100 nM; overnight immunoprecipitation incubation + 20 h enzymatic hydrolysis) specifically binds to phosphorylated tau (p217+tau). The target peptides are enriched by immunoprecipitation, and the dual-phosphorylated tau peptide SRTPSLPTPPTREPK?2p containing the pT217 site can be detected, confirming the antibody's high affinity and selective capture ability for phosphorylated tau^[2].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

1. Posdinemab (1-60 mg/kg; single dose; intravenous injection) shows good safety and tolerability, linear serum pharmacokinetics, and dose-dependent decreases in free and total p217+tau levels in cerebrospinal fluid (CSF)^[1].
2. Posdinemab detects the dual-phosphorylated tau peptide SRTPSLPTPPTREPK?2p (containing the pT217 site) in CSF, and decreases the total p217+tau level after treatment^[2].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

4137  [NCBI]

P10636

ELISA, FACS, Functional assay

Unconjugated

The product can be reconstituted/diluted with sterile PBS or saline.

145.331 kDa

2517973-04-3

Liquid

Colorless to light yellow

[Posdinemab]

Shipping with dry ice.

Please store the product under the recommended conditions in the Certificate of Analysis.

• 
  Human IgG1 kappa

• [1]. Galpern WR, et al. Phase 1 Studies of the Anti-Tau Monoclonal Antibody JNJ-63733657 in Healthy Participants and Participants with Alzheimer's Disease. J Prev Alzheimers Dis. 2024;11(6):1592-1603.  [Content Brief]

  [2]. Bijttebier S, et al. Development of immunoprecipitation - two-dimensional liquid chromatography-mass spectrometry methodology as biomarker read-out to quantify phosphorylated tau in cerebrospinal fluid from Alzheimer disease patients. J Chromatogr A. 2021 Aug 16;1651:462299.  [Content Brief]

  [3]. Panza F, et al. Clinical development of passive tau-based immunotherapeutics for treating primary and secondary tauopathies. Expert Opin Investig Drugs. 2023 Jul-Dec;32(7):625-634.  [Content Brief]