The Improving Outcomes in Relapsed-Refractory Diffuse Large B Cell Lymphoma: The Role of CAR T-Cell Therapy

Diffuse large B cell lymphoma, not otherwise specified (DLBCL-NOS) is the most common aggressive lymphoma and can be cured with CHOP-R immunochemotherapy in 60% of cases. The second-line therapy includes salvage regimens followed by autologous stem cell transplantation (ASCT), which offers a cure to a minority of patients due to limitations in efficacy and eligibility. These data present the unmet need in the field, and this review article focuses on how second-generation chimeric antigen receptor T (CAR T) cell therapy targeting CD19 antigen may improve the outcomes with relapsed/refractory DLBCL. In heavily pretreated patients, who have dismal outcomes with conventional therapy, all three approved products—tisangenlecleucel (tisa-cel), axicabtagene ciloleucel (axi-cel), and lisocabtagene maraleucel (liso-cel) have shown durable, unprecedented complete responses with the potential for cure. When compared to salvage regimens and ASCT as the standard of care, axi-cel and liso-cel, unlike tisa-cel, have demonstrated superiority in long-term control. In ASCT-ineligible r/r DLBCL, liso-cel has shown a favourable benefit-risk ratio. Regarding safety, two adverse events of interest have emerged: cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome, both of which are manageable. Real-world evidence reflects the results of pivotal trials while favouring axi-cel in heavily pretreated patients, albeit with higher toxicity. The main barrier to the implementation of this treatment modality is the cost associated with the process of CAR T therapy, along with complications and reimbursement issues. However, the barriers can be overcome, and CAR T therapy has the potential to become the standard of care in relapsed/refractory DLBCL. Furthermore, with advances in the scientific engineering of CAR products and the understanding of novel treatment modalities currently being tested in clinical trials, we believe that targeted cellular therapy will become the future of relapsed/refractory DLBCL treatment.