Comparison of transplant outcomes and economic costs between biosimilar and originator filgrastim in allogeneic hematopoietic stem cell transplantation

From January 2012 to September 2015, 49 patients received biosimilar filgrastim (BF) after allogeneic bone marrow transplantation (BMT, n = 31) or peripheral stem cell transplantation (PBSCT, n = 18) in our institution. To evaluate the clinical impact of BF on transplant outcomes of these patients, we compared hematological recovery, overall survival (OS), disease-free survival (DFS), transplantation-related mortality (TRM), cumulative incidence of relapse (CIR), and acute and chronic graft-versus-host disease (GVHD) with those of control patients who received originator filgrastim (OF) after BMT (n = 31) or PBSCT (n = 18). All cases were randomly selected from a clinical database in our institution. In both the BMT and PBSCT settings, neutrophil recovery (17 vs. 19 days in BMT; 13 vs. 15 days in PBSCT) and platelet recovery (27 vs. 31 days in BMT; 17 vs. 28 days in PBSCT) were essentially the same between BF and OF. They were also comparable in terms of OS, DFS, TRM, CIR, and the incidence of acute GVHD and chronic GVHD. On multivariate analysis, the use of BF in both BMT and PBSCT was not a significant factor for adverse transplant outcomes. Although BF significantly reduced filgrastim costs in both BMT and PBSCT, total hospitalization costs were not significantly different between BF and OF.