MAPT and Alzheimer disease: In phase II randomized controlled trials (RCTs) of active immunization of patients with mild-to-moderate AD with the anti-Aβ vaccine AN-1792 (QS-21) most but not all participants developed significant Aβ-antibody titres [48, 49] and there was evidence of memory and function improvement and reduced CSF tau concentrations in patients with increased IgG titres [48, 49].