Now, based on this knowledge, the anti-IL−4 receptor alpha antibody (ab), dupilumab, and orally administrated Janus kinase inhibitors, which block the downstream intracellular signaling of IL−4 and IL−13, are shown to have the significant clinical effect on severe AD patients, bringing breakthrough progress to the treatment of AD [8,9,10]. This evidence concerns the gene IL4 and Alzheimer disease.