Dose-Adjusted EPOCH-Rituximab Combined With Fludarabine Provides an Effective Bridge to Reduced-Intensity Allogeneic Hematopoietic Stem-Cell Transplantation in Patients With Lymphoid Malignancies

Abstract

There is currently no standard chemotherapy regimen for patients with lymphoid malignancies being considered for reduced-intensity conditioning allogeneic hematopoietic stem-cell transplantation (RIC-alloHSCT). The ideal regimen would provide disease control and result in lymphocyte depletion to facilitate engraftment. To this end, we developed a novel regimen by adding fludarabine to dose-adjusted continuous-infusion etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin plus with or without rituximab (DA-EPOCH-F/R). One hundred forty-seven patients with lymphoid malignancy (median age, 50 years) who had heavily pretreated (median prior regimens, three) and chemo-refractory (47%) disease were treated with DA-EPOCH-F/R before RIC-alloHSCT. Patients received one to three consecutive cycles until achieving lymphocyte depletion (CD4(+) count < 200/μL) or progressive disease. Overall response rate was 41%; 39% of patients had stable disease. Toxicity included grade 4 neutropenia in 65% and thrombocytopenia in 25% of patients. DA-EPOCH-F/R resulted in lymphocyte depletion (P < .001), which was inversely associated with serum interleukin (IL) 7 and IL-15 levels. Of 147 patients, 143 patients proceeded to RIC-alloHSCT. Patients with lower CD3(+) (P < .001), CD4(+) (P < .001), and CD8(+) (P < .001) T-cell counts after DA-EPOCH-F/R were more likely to achieve full donor lymphoid chimerism by day +14 after transplant. Relative to nonresponders to DA-EPOCH-F/R, patients with complete and partial response had increased event-free survival (77.4 v 4.8 months; P < .001) and overall survival (98.5 v 16.2 months; P < .001). DA-EPOCH-F/R safely provides tumor cytoreduction and lymphocyte depletion, thereby offering a bridge to RIC-alloHSCT in patients with aggressive lymphoid malignancies.