RANDOMIZED COMPARISON OF G-CSF-CSF VS G-CSF ALONE FOR MOBILIZATION OFPERIPHERAL-BLOOD STEM-CELLS - EFFECTS ON HEMATOPOIETIC RECOVERY AFTERHIGH-DOSE CHEMOTHERAPY(GM)

Fifty patients with either lymphoid or selected solid tumor malignanci es were apheresed an identical number of times for PBSC collection aft er being randomized to receive either G-CSF 10 mu g/kg/day alone (arm I), or G-CSF at the same dose with GM-CSF 5 mu g/kg/day (arm II). Grow th factor(s) was/were given as the stem cell mobilizing agent for 5 da ys before the start of PBSC collection, and were continued throughout the 4 days of apheresis. Aspiration and cryopreservation of autologous bone marrow occurred on day 3 or 4 of growth factor(s). Thirty-one of 50 patients received one cycle only at time of evaluation, and 19 pat ients received two cycles of HDCT, each supported with PBSC with or wi thout autologous bone marrow. No patients received growth factors post -autologous stem cell transplant, unless the absolute neutrophils coun t (ANC) failed to recover to greater than or equal to 100/mu l by day +18 post-transplant. The median number of days to recovery of ANC to 1 00/mu l, 500/mu 1 and 1000/mu l, and of platelet counts to 20 000/mu l , 50 000/mu l and 100 000/mu l after either cycle 1 or cycle 2 of HDCT and the number of febrile days and platelet and PRBC transfusion requ irements was not significantly different between the two arms of the s tudy. The duration of hospitalization was similar between study arms f or cycle 1 of HDCT, but was 3.5 days less with arm II compared to arm I (P = 0.0248) for cycle 2 of HDCT. The bone marrow buffy coat and PBS C product mononuclear cell count(x 10(8)/kg) and CD34(+) cell count (x 10(6)/kg) collected by each method of stem cell mobilization was not significantly different. There is questionable clinical benefit with P BSC products mobilized with the combination of G-CSF and GM-CSF vs G-C SF alone. Perhaps different dosages, schedules, or other growth factor combinations with G-CSF might enhance these differences.