Sequencing of anti-CD19 therapies in the management of diffuse large B-cell lymphoma
Abstract. Several second- and third-line immunotherapeutic options for patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL) ineligible for autologous stem cell transplant are directed against the B-cell antigen CD19. The anti-CD19 monoclonal antibody tafasitamab, paired with the immunomodulator lenalidomide, mediates antibody-dependent cellular toxicity and cellular phagocytosis; the antibody–drug conjugate loncastuximab tesirine delivers the DNA-cross-linking agent tesirine via CD19 binding and internalization; and CD19-directed chimeric antigen receptor T-cell therapy (CAR-T) products are engineered from autologous T cells. While CD19 expression is assessed at diagnosis, clinically relevant thresholds of CD19 expression—which may not be detectable with current routine methodologies—have not been defined and may vary between CD19-directed treatment modalities. Determining optimal treatment sequencing strategies with CD19-directed therapy has been hampered by the