Systematic review and meta-analysis of nonrelapse mortality after CAR T cell therapy for lymphoma and multiple myeloma

CAR T cell therapy can improve oncologic outcomes of various types of malignancies but is also associated with toxicities that contribute to morbidity and mortality. Systematic review and meta-analysis identified 7,604 patients undergoing CAR T cell therapy for lymphoma and multipel myeloma across 18 clinical trials and 28 real-world studies. Nonrelapse mortality (NRM) was reported for 574 patients (7.55%). NRM rates varied across disease entities and were highest in patients with mantle cell lymphoma (10.6%), followed by multiple myeloma (8.0%), large B cell lymphoma (6.1%), and indolent lymphoma (5.7%). Over half (50.9%) of nonrelapse deaths were attributed to infections, followed by other malignancies (7.8%), and cardiovascular or respiratory events (7.3%). Conversely, the CAR T cell-specific side effects (ICANS, CRS, and hemophagocytic lymphohistiocytosis) represented only a minority of nonrelapse deaths (cumulatively 11.5%). The author conclude that these findings underlin the critical importance of infectious complications after CAR T cell therapy.