Teclistamab is a humanized bispecific IgG4 monoclonal antibody that targets CD3 on T cells and B-cell maturation antigen (BCMA) on multiple myeloma (MM) cells. It triggers a T cell-mediated immune response, leading to the elimination of BCMA-positive cells and exhibits the potential to treat patients with triple-class exposed relapsed/refractory multiple myeloma (R/RMM). MW: 143.66 KD.