Autologous Transplant versus Chimeric Antigen Receptor T-cell Therapy for Relapsed DLBCL in Partial Remission

Abstract

The relative efficacy of autologous hematopoietic cell transplant (auto-HCT) versus chimeric antigen receptor T-cell (CAR-T) therapy in diffuse large B-cell lymphoma (DLBCL) patients who achieve a partial remission (PR) after salvage chemotherapy is not known. Using the Center for International Blood & Marrow Transplant Research registry database, we identified adult DLBCL patients who received either an auto-HCT (2013-2019) or CAR-T treatment with axicabtagene ciloleucel (2018-2019) while in a PR by CT or PET scan. We compared the clinical outcomes between the two cohorts using univariable and multivariable regression models after adjustment for relevant baseline and clinical factors. In the univariable analysis, the 2-year progression-free survival (52% vs. 42% ; p=0.1) and the rate of 100-day non-relapse mortality (4% vs. 2% ; p=0.3) were not different between the 2 cohorts but consolidation with auto-HCT was associated with a lower rate of relapse/progression (40% vs. 53% ; p=0.05) and a superior overall survival (OS) (69% vs. 47% ; p=0.004) at 2-years. In the multivariable regression analysis, treatment with auto-HCT was associated with a significantly lower risk of relapse/progression rate (HR=1.49; p=0.01) and a superior OS (HR=1.63; p=0.008). In patients with DLBCL in a PR after salvage therapy, treatment with auto-HCT was associated with a lower incidence of relapse and a superior OS compared with CAR-T. These data support the role of auto-HCT as the standard-of-care in transplant-eligible patients with relapsed DLBCL in PR after salvage therapy.