[Immunotherapy for Alzheimer's disease targeting Aβ].

Active and passive immunization of Alzheimer model mice with Aβ showed clearance of aggregated amyloid β deposits and improved memory and learning. Although human trial was halted because of autoimmune encephalitis, the trial revealed that immunization with Aβ also deleted amyloid deposits in humans without clinical benefit. On these proof of concept, several clinical trials using monoclonal antibodies are on-going. Although solanezumab which recognizes Aβ monomer turned out ineffective in the primary endpoint, it showed significant beneficial effect in mild AD cases in the secondary outcome. Solanezumab is now on a large scale phase III trial in mild AD cases in the world. If it turns out to be effective, it will be the first disease modifying drug for AD in a few years. However, since monoclonal antibodies are extremely expensive, less expensive and long acting active immunization will be widely accepted. More effective and sophisticated vaccines such as DNA vaccine and recombinant viral vaccines will be utilized in future.