Tbo-filgrastim versus filgrastim for stem cell mobilization and engraftment in autologous hematopoietic stem cell transplant patients: A retrospective review

Efficacy and cost of G-CSF derivatives for prophylaxis of febrile neutropenia in lymphoma and multiple myeloma patients underwent autologous hematopoietic stem cell transplantation

OBJECTIVES

To compare the efficacies and costs between pegfilgrastim and filgrastim prophylaxis for FN post-ASCT for lymphoma and multiple myeloma patients.

METHODS

43 patients who received pegfilgrastim (6 mg) were compared to a retrospective cohort of 129 patients that had received filgrastim post-ASCT. Hematopoietic recovery time, FN incidence and treatment costs were assessed and compared.

RESULTS

The mean time to absolute neutrophil count engraftment was 8.72 ± 2.38 days for the prospective pegfilgrastim group and 9.87 ± 3.13 days for the retrospective filgrastim group (P = 0.027). The incidence of FN was 18.60% and 50.39% in prospective pegfilgrastim and retrospective filgrastim groups, respectively (P = 0.000). The mean cost of filgrastim was $617.22 ± 37.87, compared with $525.78 for pegfilgrastim (P = 0.032).

DISCUSSION

Convenience, effectiveness, and safety of prophylaxis for FN in the prospective pegfilgrastim group were significantly improved compared to the retrospective filgrastim group in ASCT patients.

CONCLUSION

Pegfilgrastim prophylaxis was more effective and convenient than filgrastim for FN prophylaxis in patients post-ASCT, especially for MM patients.

Use of Biosimilar Granulocyte Colony-Stimulating Factor for Mobilization in Autologous and Allogeneic Hematopoietic Stem Cell Transplantation

The biologic medication filgrastim is approved by the Food and Drug Administration (FDA) to mobilize hematopoietic progenitor cells (HPCs) for collection by leukapheresis for autologous hematopoietic stem cell transplant (HSCT). The FDA-approved biologic tbo-filgrastim is currently used off-label for this indication in both autologous and allogeneic HSCT at the Tennessee Valley Healthcare System. The purpose of this review is to compare the efficacy of filgrastim and tbo-filgrastim for this indication. The primary outcomes were the proportion of autologous patients and allogeneic donors with a CD34+ count ≥15 × 103 cells/uL on day 4 of filgrastim or tbo-filgrastim mobilization. The secondary outcome was the use of plerixafor in the autologous population. A total of 469 subjects were identified for inclusion; 367 underwent mobilization for autologous HSCT and 102 for allogeneic HSCT donation. The primary outcome was achieved in 47.5% of patients who received filgrastim compared to 50.2% who received tbo-filgrastim in the autologous population (p = 0.67). Among donors for allogeneic HSCT, there was no difference between those eligible for collection on day 4 of filgrastim or tbo-filgrastim administration (97.6% vs. 100%, p = 0.41). No significant difference was identified in the number of patients requiring plerixafor use in the autologous HSCT population. The use of the biosimilar tbo-filgrastim for mobilization in either autologous HSCT patients or allogeneic HSCT donors has comparable outcomes to that of the biotherapeutic reference product filgrastim at a reduced cost to the healthcare system.