Recent Progress Towards Vaccines and Antibody-based Therapies Against Alzheimer's Disease

Alzheimer's disease (AD), one of the progressive neurodegenerative disorders, is characterized by clinical features such as memory loss, acquired skill loss, apraxia, and interpersonal and social communication disorders. The AD hallmarks at the neuropathological level include intracellular neurofibrillary tangles constituted by the hyperphosphorylated tau protein as well as the senile extracellular plaques dominated by the amyloid-β (Aβ) deposits. At present, AD treatment that mainly targeted towards improving symptoms and effective drugs to delay or stop disease progression is lacking. Vaccines and antibody-based therapies are a type of natural, synthetic, and gene recombinant biological product that treat or prevent disease progression by stimulating specific or non-specific immune responses. Compared with traditional targeted drugs, vaccines and antibodybased therapies have better safety and effectiveness and can even maintain the expression and stability of Aβ and Tau proteins in patients for a long time. Logically, vaccines and antibody-based therapies are somewhat different from traditional drugs because these drugs can achieve the therapeutic effect of AD by activating immune cells and regulating the immune system of patients themselves, thereby clearing disease-related proteins and long-term survival. Complete cure is also observed in some patients after receiving the immunotherapy. Currently available vaccines and antibody-based therapies mainly target Aβ and phosphorylated tau proteins. There are 44 vaccines and antibodybased therapies for AD, among which nine drugs are discontinued, three drugs are inactive, eleven drugs are in clinical phase 1, twelve drugs are in clinical phase 2, and seven drugs are in clinical phase 3. Currently, no vaccines and antibody-based therapies have been approved for AD treatment. In this paper, we review and analyse the research progress of vaccines and antibody-based therapies that are used to treat AD.