Immunotherapy for Multiple Myeloma, Past, Present, and Future: Monoclonal Antibodies, Vaccines, and Cellular Therapies.

Multiple myeloma is a disorder of terminally differentiated plasma cells, characterized by immune dysfunction, deregulated signaling within the bone marrow stromal compartment, and a microenvironment that fosters immunosuppression. Immunomodulatory techniques, such as allogeneic hematopoietic stem cell transplant (allo-HCT) and donor lymphocyte infusion (DLI), demonstrate long-term disease control via manipulation of the immunologic milieu. However, allo-HCT is associated with numerous toxicities including infectious complications and graft versus host effect and is not suitable for many patients. Novel agents and cellular-based therapies aim to restore the balance of humoral and adaptive immunity without the morbidity of allo-HCT and DLI. In the following review, we will summarize the use of immunomodulatory techniques in multiple myeloma, including monoclonal antibodies, vaccine therapy, checkpoint inhibitors, autologous T cells, and engineered T cells.