<p>Disclosed are a novel therapeutic method and a novel therapeutic agent for the treatment of Alzheimer's disease. Specifically, disclosed are: an antiinflammatory cytokine; an anti-inflammatory cytokine gene; and a negative-strand RNA viral vector carrying an anti-inflammatory cytokine gene, each of which can be used for the treatment of Alzheimer's disease or the development of a therapeutic agent for Alzheimer's disease. Also disclosed is a pharmaceutical composition for the treatment or prevention of Alzheimer's disease, which comprises the cytokine or the vector. Further disclosed is a method for the treatment of Alzheimer's disease, which comprises the step of administering an antiinflammatory cytokine or a vector such as a negative-strand RNA viral vector carrying an antiinflammatory cytokine gene. It becomes possible to provide a novel gene therapy for Alzheimer's disease.</p>
