Dear Editor,
Alzheimer's disease (AD) is the most common cause of dementia among the older population,and is characterized by amyloid-beta (Aβ) accumulation,hyperphosphorylation of tau,and finally neurodegeneration in the brain[1].Aβ is the major pathological agent in AD,thus currently most efforts in developing therapies for AD target this peptide.The most promising therapy for this disease is immunotherapy,which shows high efficacy in improving AD-type pathology and cognition in mouse models.However,clinical trials of immunotherapy against Aβ have not yet succeeded,partly due to adverse effects.Another potent therapeutic method for AD is screening drugs currently used in clinical practice,which might significantly reduce the risk of adverse events[2].