Bispecific Antibodies in Multiple Myeloma: A Concise Review of Current Treatments

The treatment landscape for multiple myeloma (MM) has evolved significantly over the years; however, the disease remains incurable. Heavily pretreated patients with refractory disease to anti-CD38 therapies, proteasome inhibitors (PIs), and immunomodulatory drugs (IMiDs) face a very poor prognosis. Bispecific antibodies (BsAbs) are the newest, and most promising available therapy for heavily pretreated patients with relapsed refractory multiple myeloma (RRMM). BsAbs primarily rely on T cell activation to target cancer cells by binding malignant plasma cells to cytotoxic T cells via surface antigens. BsAbs consist of two binding sites: one that targets a specific antigen on the surface of MM cells, such as B-cell maturation antigen (BCMA), G-protein-coupled receptor class C group 5 member D (GPRC5D), or fragment crystallizable receptor-like 5 (FcRH5), and another that binds to CD3, a T-cell receptor. Ongoing research aimed at optimizing sequencing strategies, mitigating toxicity, and evaluating combination approaches will be critical to maximizing the durability of response and improving long-term outcomes in this high-risk population.