Phase III randomized study comparing 5 or 10 microg per kg per day of filgrastim for mobilization of peripheral blood progenitor cells with chemotherapy, followed by intensification and autologous transplantation in patients with nonmyeloid malignancies.
BACKGROUND
It is not known whether increasing the dose of filgrastim after mobilizing chemotherapy improves collection of peripheral blood progenitor cells (PBPC) and leads to faster hematopoietic engraftment after autologous transplantation.


METHODS
A randomized, open-label, multicenter trial was carried out in patients with breast cancer, multiple myeloma, and lymphoma, in which patients were randomized to receive 5 or 10 microg per kg per day of filgrastim after standard chemotherapy to mobilize PBPCs. After high-dose chemotherapy, the components from the first two leukapheresis procedures were returned, and all patients received 5 microg per kg day of filgrastim after transplantation.


RESULTS
A total of 131 patients were randomized, of whom 128 were mobilized (Group A, 5 microg/kg, n = 66; Group B, 10 microg/kg, n = 62) and 112 were transplanted. Only six patients were not transplanted because of insufficient CD34+ cell numbers. The median number of CD34+ cells collected in the first two leukapheresis procedures tended to be higher in Group B than in Group A (12.0 vs. 7.2 x 10(6)/kg, NS), but after transplantation there was no significant difference in median times to platelet (9 days in both groups) or neutrophil (8 days in both groups) engraftment or the number of platelet transfusions (three in both groups). A subsequent subgroup analysis separating patients transplanted after first- or second-line chemotherapy also showed no measurable impact of filgrastim dose on the median CD34+ cell yield or on platelet engraftment in either subgroup.


CONCLUSIONS
PBPC mobilization with chemotherapy and 5 microg per kg of filgrastim is very efficient, and 10 microg per kg of filgrastim does not provide additional clinical benefit.
André
Marc
M
Groupe Oncologie UCL, Saint-Luc Academic Hospital, Brussels, Belgium. andre.marc@chndrf.be
Baudoux
Etienne
E
Bron
Dominique
D
Canon
Jean-Luc
JL
D'Hondt
Véronique
V
Fassotte
Marie-France
MF
D'Hondt
Lionel
L
Fillet
Georges
G
Humblet
Yves
Y
Jerusalem
Guy
G
Vermeulen
Philippe
P
Symann
Michel
M
Beguin
Yves
Y
D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000628:therapy; D005260:Female; D000069585:Filgrastim; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology*; D019650:Hematopoietic Stem Cell Mobilization; D018380:Hematopoietic Stem Cell Transplantation / Q000009:adverse effects; D006801:Humans; D007937:Leukapheresis; D008223:Lymphoma / Q000628:therapy; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000628:therapy; D011994:Recombinant Proteins; D014182:Transplantation, Autologous
D000970:Antineoplastic Agents; D011994:Recombinant Proteins; D016179:Granulocyte Colony-Stimulating Factor; D000069585:Filgrastim