Quilizumab (Anti-Human IGHE Recombinant Antibody) is a humanized IgG1κ monoclonal antibody targeting immunoglobulin epsilon (also konwn as: IGHE, IgE). Quilizumab targets the M1-prime fragment of membrane-expressed IGHE/IgE, leading to IGHE/IgE switching and memory B cell depletion. Quilizumab has potential in asthma research[1].