Photo Credit: Panuwat Dangsungnoen
The following is a summary of “Autologous Transplant (auto-HCT) Is Associated with Improved Clinical Outcomes Compared to CAR-T Therapy in Patients (pts) with Large B-Cell Lymphoma (LBCL) Achieving a Complete Remission,” published in the December 2023 issue of Hematology by Shadman et al.
Autologous hematopoietic stem cell transplantation (auto-HCT) and CAR-T cell therapy are both established treatment options for patients with relapsed large B-cell lymphoma (LBCL), including those who achieve complete remission (CR).
Researchers conducted a retrospective study to assess the comparative outcomes of LBCL patients treated with auto-HCT or CAR-T therapy while in CR.
They included patients aged 18-75 with DLBCL or primary mediastinal lymphoma who underwent CAR-T (between 2018-2021) or auto-HCT (between 2015-2021) while in CR by PET or CT. The analysis used data from the Center for International Blood & Marrow Transplant Research (CIBMTR) registry. Primary endpoints covered progression-free survival (PFS) and OS. Secondary endpoints involved treatment-related mortality (TRM) and relapse rate.
The results showed 360 LBCL patients in CR before CAR-T (n=79; tisa-cel 53%, axi-cel 46%, and liso-cel 1%) or auto-HCT (n=281). Median follow-up was 24.7 months (range 3.3-49.4) for CAR-T and 49.7 months (range 3.0-95.4) for auto-HCT. PET scan confirmed CRs in 90% of CAR-T patients and 99.6% of auto-CAR-T patients (P<0.01). The most common lymphodepletion regimen for CAR-T was Cy/Flu (82.3%), and for auto-HCT, it was BEAM (77.6%). Thirty-seven (13.2%) auto-HCT patients had CAR-T, but none had subsequent auto-HCT. In univariate analysis, CAR-T treatment correlated with a higher 2-year relapse rate (48% vs. 27.8%; P<0.001), a reduced 2-year PFS (47.8% vs. 66.2%; P<0.001), and diminished 2-year OS (65.6% vs. 78.9%; P=0.037). No disparity appeared in 2-year TRM rates (4.1% vs. 5.9%; P=0.673). Similarly, for patients with early (12 months) treatment failure (CAR-T =57 and auto-HCT=163), CAR-T treatment linked to a higher 2-year relapse rate (45.9% vs. 22.8%; P<0.001) and an inferior 2-year PFS (48.3% vs.70.9%.; P<0.001) compared to auto-HCT, while no difference emerged in 2-year OS or TRM. In the multivariable analysis, CAR-T treatment was associated with a higher relapse risk (HR 2.18; P<0.0001) and inferior PFS (HR 1.83; P=0.0011) compared to auto-HCT. No distinction appeared in the risk of TRM (HR 0.59; P=0.36) or OS (HR 1.44; P=0.12).
They concluded that Autologous HCT was associated with superior clinical outcomes compared to CAR-T in relapsed LBCL patients achieving complete remission.