Crossover study of the haematological effects and pharmacokinetics of glycosylated and non-glycosylated G-CSP in healthy volunteers

A cross-over study of glycosylated and nonglycosylated G-CSF was performed in 20 healthy male volunteers to compare the effects of the different forms of G-CSE the extent of inter-individual progenitor cell mobilization and to determine whether any differences observed were related to the serum concentrations of G-CSF attained. The peak WBC achieved during 6d of G-CSF administration at a dose of 5 mu g/kg/d was significantly higher with the glycosylated than the non-glycosylated product (P = 0.02) as was the peak level of granulocyte;monocyte colony forming cells (GM-CFC) (P=0.03). The average GM-CFC count on days 5, 6 and 7 was 28% higher with the glycosylated product (P=0.003). Serum concentrations of G-CSF achieved were significantly higher with the non-glycosylated G-CSE however, suggesting that the difference in bio-efficacy was not due to a difference in G-CSF stability. Marked inter-individual variation in progenitor mobilization was observed, but this was not related to serum G-CSF levels, The G-CSF concentrations on day 6 were approximately one third of those on day 1, with both forms of G-CSE.