Randomized Trial of Sequential Administration of G-CSF and GM-CSF vs. G-CSF Alone Following Peripheral Blood Progenitor Cell Autograft in Solid Tumors

A trial was conducted to investigate whether the sequential administration of recombinant human granulocyte colony-stimulating factor (G-CSF) and recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) could accelerate reconstitution of hematopoiesis, compared with G-CSF alone following high-dose chemotherapy (HDCT). A group of 34 consecutive patients with solid tumors undergoing HDCT and autologous peripheral blood progenitor cell (PBPC) transplantation was studied. Conditioning regimen included carboplatin, etoposide, mitoxantrone, and melphalan for breast cancer and cyclophosphamide or ifosfamide, carboplatin, and etoposide for the other tumors. HDCT was delivered from day -3 to day -1. PBPC were infused on day 0, and on the same day growth factors were administered subcutaneously (s.c.) 5 microg/kg each. Seventeen patients were randomized to receive G-CSF from day 0 to day 13 after HDCT (arm A), and 17 patients received G-CSF from day 0 to day 6 and GM-CSF from day 7 to day 13 (arm B). Patients were stratified, and their characteristics were homogeneous in both arms for age, performance status, and number of previous chemotherapy courses and CD34+ infused. The median time to absolute neutrophil count (ANC) >500/microl was 10 days in arm A and 9 days in arm B (p = 0.96). Days to platelet (PLT) count >20,000 were not different in the two treatment arms (p = 0.1), but patients randomized to arm A had a lower platelet count compared with patients in arm B. One month after PBPC transplantation, a statistically significant difference in PLT count was observed (arm A median 150x10(3)/microl (90-310), arm B median 254x10(3)/microl (117-387),p = 0.0013). The days patients had fever >38 degrees C were 39 in arm A and 26 in arm B (p = 0.18). The difference in the length of hospital stay was not statistically significant between the groups (Mann-Whitney sum rank test). After a median follow-up of 30 months, 21 patients were alive and 20 were disease free. These data show that the two growth factors are associated with different patterns of hematopoietic recovery, and larger randomized trials in groups of more homogeneous patients will be needed to define the effects and benefits of combination growth factor therapies.