A single dose of 6 or 12 mg of pegfilgrastim for peripheral blood progenitor cell mobilization results in similar yields of CD34+ progenitors in patients with multiple myeloma.
BACKGROUND
Current regimens for peripheral blood progenitor cell (PBPC) mobilization in patients with multiple myeloma are based on daily subcutaneous injections of granulocyte-colony-stimulating factor (G-CSF) starting shortly after cytotoxic therapy. Recently a polyethylene glycol-conjugated G-CSF (pegfilgrastim) was introduced that has a substantially longer t(1/2) than the original formula.


METHODS
The use of pegfilgrastim was examined at two dose levels for PBPC mobilization in patients with Stage II or III multiple myeloma. Four days after cytotoxic therapy with cyclophosphamide (4 g/m(2)), a single dose of either 6 mg pegfilgrastim (n = 15) or 12 mg pegfilgrastim (n = 15) or daily doses of 8 microg per kg unconjugated G-CSF (n = 15) were administered. The number of circulating CD34+ cells was determined during white blood cell (WBC) recovery, and PBPC harvesting was performed by large-volume apheresis.


RESULTS
Pegfilgrastim was equally potent at 6 and 12 mg with regard to mobilization and yield of CD34+ cells. No dose dependence was observed because CD34+ cell concentration peaks were 131 and 85 per microL, respectively, and CD34+ cell yield was 10.2 x 10(6) and 7.4 x 10(6) per kg of body weight, respectively. Pegfilgrastim in either dose was associated with a more rapid WBC recovery (p = 0.03) and an earlier performance of the first apheresis procedure (p < 0.05) in comparison to unconjugated G-CSF. No difference regarding CD34+ cell maximum and yield could be observed.


CONCLUSIONS
A single dose of 6 mg pegfilgrastim is equally potent as 12 mg for mobilization and harvest of PBPCs in patients with multiple myeloma. Because no dose dependency was seen at these dose levels, this might be also true for even smaller doses.
Bruns
Ingmar
I
Department of Hematology, Oncology and Clinical Immunology, Heinrich Heine University, Duesseldorf, Germany.
Steidl
Ulrich
U
Kronenwett
Ralf
R
Fenk
Roland
R
Graef
Thorsten
T
Rohr
Ulrich-Peter
UP
Neumann
Frank
F
Fischer
Johannes
J
Scheid
Christof
C
Hübel
Kai
K
Haas
Rainer
R
Kobbe
Guido
G
D000328:Adult; D000368:Aged; D018952:Antigens, CD34 / Q000378:metabolism; D005260:Female; D000069585:Filgrastim; D016179:Granulocyte Colony-Stimulating Factor / Q000008:administration & dosage*; D019650:Hematopoietic Stem Cell Mobilization / Q000379:methods*; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000378:metabolism; D006801:Humans; D007937:Leukapheresis; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000628:therapy*; D036102:Peripheral Blood Stem Cell Transplantation; D011092:Polyethylene Glycols; D011994:Recombinant Proteins; D014182:Transplantation, Autologous
D018952:Antigens, CD34; D011994:Recombinant Proteins; D016179:Granulocyte Colony-Stimulating Factor; C455861:pegfilgrastim; D011092:Polyethylene Glycols; D000069585:Filgrastim