Efficacy of deferred dosing of granulocyte colony-stimulating factor in autologous hematopoietic transplantation for multiple myeloma

Routine administration of G-CSF following autologous hematopoietic SCT (ASCT) expedites ANC recovery and reduces hospitalization by 1–2 days; it has no impact on febrile neutropenia, infections, morbidity, mortality, event-free survival or OS. To determine whether delayed G-CSF dosage could result in equivalent ANC recovery and thereby improve cost effectiveness, we deferred the administration of G-CSF until WBC recovery had begun. A total of 117 patients with multiple myeloma received ASCT from January 2005 to September 2012. Of these, 52 were in the conventional dosing group (CGD) and received G-CSF from Day +7 for a median of five doses. In the deferred dosing group (DGD), 65 patients received G-CSF from median day 14 post transplant for a median of zero doses. There was no difference between groups in the incidence or duration of febrile neutropenia, duration of ⩾grade III mucositis, weight gain, rash, engraftment syndrome or early death (100 days). The DGD group had a significantly longer time to neutrophil engraftment than the CGD group (15 days vs 12 days; P<0.0001), a longer period of severe neutropenia (<100/μL; 8 days vs 6 days; P<0.0001), longer treatment with intravenous antibiotics (7 days vs 5 days; P=0.016) and longer hospital stay (19 days vs 17 days; P=<0.0001). Although the cost of G-CSF was lower in the DGD group (mean $308 vs $2467), the additional hospitalization raised the median total cost of ASCT in this group by 17%. There was, however, no adverse effect of deferred dosing on the rate of febrile neuropenic episodes or Day 100 survival, so that deferred dosing of G-CSF may be suitable for patients receiving ASCT as outpatients, for whom longer hospital stay would not be an offsetting cost.