Isatuximab is a humanized, IgG1-derived monoclonal antibody (mAb) produced from a Chinese hamster ovary (CHO) cell line. Structurally, isatuximab is comprised of two identical immunoglobulin kappa light chains and two identical immunoglobulin gamma heavy chains. It is a cytolytic antibody targeted against CD38, a glycoprotein found on the surface of some immune cells that is highly expressed by malignant plasma cells in multiple myeloma. Along with daratumumab, another anti-CD38 monoclonal antibody, isatuximab constitutes a novel treatment modality for patients with difficult-to-treat multiple myeloma.