Improving engraftment in autologous hematopoietic stem cell transplantation: comparing pegfilgrastim with filgrastim in an outpatient setting

BACKGROUND: Febrile neutropenia, a frequent complication in patients undergoing autologous stem cell transplantation, increases morbidity and hospitalization costs. OBJECTIVE: The aim of this study was to compare the efficacy of two formulations of pegylated filgrastim with filgrastim in patients who received autologous stem cell transplantation as outpatients for lymphoma or myeloma. METHODS: Thirty patients were randomized to receive a single 6 mg dose of either reference or biosimilar pegfilgrastim on Day +1. A retrospective Control Group of fifty-three patients who received filgrastim was included. MAIN RESULTS: The median times to neutrophil engraftment were 10, 9 and 11 days for the innovator pegfilgrastim, biosimilar pegfilgrastim (p-value = 0.14), and filgrastim (p-value = 0.0001), respectively. The median times to platelet engraftment were 10 days for both of the pegfilgrastim groups and 12 days for the filgrastim group (p-value = 0.0001). Febrile neutropenia incidence was lower in the pegfilgrastim group (6.7%) than in the filgrastim group (24.5%; p-value = 0.04). Cost analysis showed higher costs for the innovator pegfilgrastim, with filgrastim having the lowest cost of the three formulations. CONCLUSION: The innovator and the biosimilar pegfilgrastim demonstrated similar efficacy in engraftment speed and febrile neutropenia incidence. Pegfilgrastim was associated with faster engraftment, a lower incidence of platelet transfusion, and a lower incidence of febrile neutropenia.