The most common dementia worldwide, Alzheimer’s disease is often diagnosed via biomarkers in cerebrospinal fluid, including reduced levels of Aβ1–42, and increases in total tau and phosphorylated tau-181. Here we describe results of a Phase 2a study of a promising new drug candidate that significantly reversed all measured biomarkers of Alzheimer’s disease, neurodegeneration and neuroinflammation. PTI-125 is an oral small molecule drug candidate that binds and reverses an altered conformation of the scaffolding protein filamin A found in Alzheimer’s disease brain. Altered filamin A links to the α7-nicotinic acetylcholine receptor to allow Aβ42’s toxic signaling through this receptor to hyperphosphorylate tau. Altered filamin A also links to toll-like receptor 4 to enable Aβ-induced persistent activation of this receptor and inflammatory cytokine release. Restoring the native shape of filamin A prevents or reverses filamin A’s linkages to the α7-nicotinic acetylcholine receptor and tolllike receptor 4, thereby blocking Aβ42’s activation of these receptors. The result is reduced tau hyperphosphorylation and neuroinflammation, with multiple functional improvements demonstrated in transgenic mice and postmortem Alzheimer’s disease brain.

(1) H.-Y. Wang, Z. Pei, K.-C. Lee, E. Lopez-Brignoni, B. Nikolov, C.A. Crowley, M.R. Marsman, R. Barbier, N. Friedmann, L.H. Burns The Journal of Prevention of Alzheimer’s Disease (JPAD) 2020 in press

Aricle H.Y. Wang