Pooled Analysis on Bispecific Antibody-Related Toxicities in Multiple Myeloma

Background: Multiple myeloma (MM) is a hematologic malignancy caused by the uncontrolled proliferation of malignant plasma cells in the bone marrow. Bispecific antibodies (BsAbs) are a new novel class of drugs currently assessed in the setting of relapsed/refractory MM (RRMM), with impressive outcomes. BsAbs are designed to direct against specific antigenic epitopes on the surface of malignant plasma cells, with two main categories: B-cell maturation antigen (BCMA) or other (non-BCMA) antigens which include G-protein coupled receptor family C group 5 member D (GPRC5D) and Fc Receptor-Like 5 (FcRH5). Methods: We conducted a pooled analysis of the available literature on BsAbs reported in the form of abstract or full peer-reviewed publications, published until June 2023, using PubMed, Scopus, Google Scholar and Embase databases. BsAbs were classified into two groups: BCMA and non-BCMA-directed agents. Studies on BsAbs used in combination with other plasma-cell directed agents, and studies reporting outcomes of patients who had prior exposure of other BsAbs were excluded. BsAb included in our study were the following: Teclistamab, Elranatamab, REGN-5458, AMG420, AMG701, CC-93269, TNB-383B, Linvoseltamab, Talquetamab, and Cevostamab. We collected safety data including cytokine release syndrome (CRS), neurotoxicity, infections rates and hematologic toxicities. We used T-test statistics to determine significance (p-value