Based on the distinct folds of AD filaments, recombinant tau, and other tauopathies, the present study focused on AD seed-templated tau both in a cellular environment and under cell-free conditions (AD seed-induced real-time quaking-induced conversion: RT-QuIC) with the aim of repurposing FDA-approved drugs for the inhibition of AD tau aggregation. Here, MAPT is linked to Alzheimer disease.