Reduced-Intensity Conditioning With Fludarabine and Busulfan Versus Fludarabine and Melphalan for Patients With Acute Myeloid Leukemia: A Report From the Acute Leukemia Working Party of the European Group for Blood and Marrow Transplantation
Abstrakt
BACKGROUND: Fludarabine plus busulfan (FB) and fludarabine plus melphalan (FM) are 2 widely used reduced-intensity conditioning (RIC) regimens for allogeneic hematopoietic stem cell transplantation (allo-SCT). METHODS: The current survey compared transplantation outcomes for a cohort of 394 acute myeloid leukemia (AML) patients given bone marrow or peripheral blood stem cells from human leukocyte antigen-identical siblings after FB (n5218) or FM (n5176).
Patients given manipulated grafts and those given Tcell- depleting agents (anti-thymocyte globulins or alemtuzumab) were not included. RESULTS: At the time of transplantation, 266 patients (68%) were experiencing their first complete remission (CR), 69 (18%) were experiencing a later CR, and 59 (15%) had advanced disease.
The incidences of acute and chronic graft-versus-host disease were similar in the 2 groups of patients. The 2-year relapse incidence (RI), nonrelapse mortality (NRM) rate, leukemia-free survival (LFS) rate, and overall survival (OS) rate were 31%63%, 18%63%, 51%64%, and 54%64%, respectively, for FB patients and 20% 63% (P5.007), 20% 63% (P5.4), 60% 64% (P5.08), and 62%64% (P5.2), respectively, for FM patients.
Among FB patients given intravenous busulfan (n581), the 2-year RI, NRM, LFS, and OS rates were 26%65% (P5.43 vs FM patients), 25%66% (P5.18), 49%67% (P5.07), and 54%67% (P5.13), respectively. In multivariate analyses, FM was associated with a lower RI (hazard ratio [HR], 0.5; P5.01) and a trend toward higher NRM (HR, 1.6; P5.1) with similar LFS (HR, 0.8; P5.2) and OS (HR, 0.9; P5.6).
CONCLUSIONS: These results suggest that although FM provides better AML control than FB as an RIC regimen for allo-SCT, the 2 regimens provide similar survival. Multicenter randomized studies are needed to confirm these findings.