The most profitable and promising drugs made by the pharma company Eisai (“AY-sigh”) treat this disease. In 2021, three FDA advisors resigned to protest the approval of an erstwhile-blockbuster Biogen drug that failed to improve this (20[1])disease’s (20[1])prognosis. (20[1])Sylvain Lesné faked Western (20[1])blots to prove the toxic oligomer (20[2])Aβ*56 (“A-beta-star-56”) causes this disease. (20[3])In 2022, the clinical success of lecanemab (20[1])(“luh-CAN-uh-mab”) validated (20[2])a (20[1])long-standing hypothesis that this disease occurs when (*) secretases (“SEH-cruh-tazes”) cleave a precursor protein and leave its insoluble beta (10[1])peptide (0[1])behind. (10[4])Two hallmarks of this (10[1])disease are fibrous tangles of tau (10[3])protein (10[6])and (10[1])aggregated (10[2])amyloid plaques. (10[1])This disease’s “early onset” occurs before age 65. For 10 points, name this neurodegenerative disease, (10[2])the leading cause of dementia. ■END■ (10[1])