Filgrastim as an alternative to donor leukocyte infusion for relapse afterallogeneic stern-cell transplantation

Purpose: Donor leukocyte infusion (DLI) effectively treats relapse after al logeneic stem-cell transplantation (alloSCT), but the response may require several months and may be associated with significant toxicity. Filgrastim has also been observed to effectively treat leukemic relapse after alloSCT. A retrospective analysis was performed to determine the effectiveness of f ilgrastim in treating relapses after alloSCT. Patients and Methods: Fourteen patients with hematologic malignancies were treated with filgrastim at relapse after alloSCT. Filgrastim was given at 5 mcg/kg/d subcutaneously for 21 consecutive days. Response was evaluated at 7 days after completion of filgrastim. Immunosuppressants, if present, wer e rapidly tapered to complete discontinuation at the time of relapse. Results: Three patients were not assessable for response because additional therapy was necessary before completion of filgrastim. Six patients (43%) achieved a complete response on an intent-to-treat basis. When response was evaluated based on relapse type, three of four cytogenetic relapses, two o f three morphologic relapses, and one of four hematologic relapses achieved a complete remission. Two responses were observed in patients who were com pletely off of any immunosuppression at the time of relapse. Six patients d eveloped chronic graft-versus-host disease. The event-free and overall surv ival rates for all 14 patients are 43% and 73%, respectively, Conclusion: The use of filgrastim with rapid discontinuation of immunosuppr ession results in response rates that are similar to results using DLI. Fil grastim could be considered as an alternative or an adjunct to DLI for rela pses after alloSCT. J Clin Oncol 18:2269-2272. (C) 2000 by American Society of Clinical Oncology.