Tokyo, Japan – December 10, 2024 – APRINOIA Therapeutics has developed a novel enzyme-linked immunosorbent assay (ELISA) that employs its proprietary monoclonal antibody APNmAb005, which has high selectivity and sensitivity to its target molecule high-molecular-weight oligomeric tau (HMWoTau) species. The oligomer species robustly increased in the brain at Braak stage V and VI of Alzheimer’s disease (AD).

APNmAb005-ELISA was demonstrated to be the first assay system, specifically detecting HMWoTau as a minimum oligomer size (approximately 2000 kD) in clinically measurable low concentrations. The research outcome was published in The FASEB Journal on November 20, 2024 (https://doi.org/10.1096/fj.202401704R).

Figure: HMWoTau species-specific APNmAb005-ELISA was developed with a detection limit of 0.3 pg rhHMWoTau/well, enabling AD-specific signal detection from 1 ng brain lysate protein/well. APNmAb005’s target was identified as HMWoTau (approximately 2000 kD, about 30 nm in diameter, see green globular oligomer particle) and another more oligomerized tau species (roughly estimated as 7-fold length). Human frontal lobe (Braak Stage I–VI) showed statistically significant increases in HMWoTau species at Braak stage V/VI of AD under the detection-limit levels at Braak stage I–III, indicating HMWoTau species’ disease-specific generation.

APNmAb005 is our originally discovered anti-tau antibody that binds to its target molecular species of oligomers and aggregates, being preferentially localized in synapses in pathological brain tissues. APNmAb005 is currently in Phase I clinical trial to evaluate its safety and tolerability.

“Our highly sensitive and novel APNmAb005-ELISA will not only elucidate the etiological role of HMWoTau species in tau-associated neurodegenerative diseases, including Alzheimer’s disease, but also open avenues for precision medicine by its application to potential diagnostics. The research is one of testaments to APRINOIA’s commitment for advancing precision medicine in neurodegenerative diseases,” said Dr. Masaomi Miyamoto, Executive Vice President of APRINOIA Therapeutics, Japan.

About APRINOIA Therapeutics

APRINOIA is a late-stage biotechnology company committed to protecting patients’ brain health and changing outcomes of neurodegenerative diseases through first-in-class and best-in-class diagnostic tools and novel therapies. The company aims to bring precision medicine to neuroscience by identifying and targeting the protein aggregates of tau, alpha-synuclein and other proteins that play a critical role in the pathogenesis of many neurodegenerative diseases, such as Alzheimer’s and Parkinson’s diseases.