Granulocyte colony-stimulating factor alone at 12 microg/kg twice a day for 4 days for peripheral blood progenitor cell priming in pediatric patients.

In children, the optimal mobilization schedule for harvesting peripheral blood progenitor cells (PBPC) is an issue of continuous research. We have studied a schedule based on high and daily divided doses of G-CSF (12 microg/kg body weight twice daily) for 4 days for PBPC priming. Toxicity related to G-CSF was observed in 13 patients (23%), mainly mild bone pain and myalgia. The median CD34(+)cell number collected was 4.4 (0.4-35 x 10(6)/kg body weight), with 46 patients achieving 2 x 10(6)/kg body weight (83.6%) after a single large volume leukapheresis. In conclusion, this mobilization schedule allows safe and efficient collection of the minimum target CD34(+) cell dose in most pediatric patients by only one procedure.