Risk of infections with B-cell maturation antigen-directed immunotherapy in multiple myeloma
2] Impaired immune reconstitution, cytopenia, B-cell aplasia, and hypogammaglobinemia (HGG) can compound preexisting MM-induced immunosuppression. In addition, bsAb can redirect and activate regulatory T cells, thus theoretically increasing the risk of infections. Here, we describe the infectious complications observed across different BCMA-directed T-cell therapies (bsAb and CAR-T) in relapsed/refractory MM clinical trials at our center. Infections confirmed by clinical, imaging, microbiologic, or histopathologic evidence were captured from day 1 of the first cycle of bsAb and day 1 of lymphodepletion chemotherapy in autologous BCMA CAR-T therapies until disease progression or last follow-up. National Cancer Institute Common Terminology Criteria for Adverse Events, version 5, was used to describe the site and grade of infections. The serum immunoglobulin G concentration was evaluated before inception of treatment and approximately monthly thereafter. Antimicrobial prophylaxis was in accordance with institutional standards for CAR-T recipients (supplemental Table Descriptive statistics and comparisons were performed using 2-sample t test for continuous variables and x 2 goodness-of-fit test for categorical variables.