DB16954 (Ezeprogind) is a small molecule drug developed to treat Progressive Supranuclear Palsy (PSP), a tauopathy-related neurodegenerative disorder, by targeting the Progranulin– Prosaposin (PGRN–PSAP) axis and enhancing lysosomal function [94]. Here, PSAP is linked to supranuclear palsy, progressive, 1.