Shortened time to recovery from chemotherapy induced neutropenia in pediatric patients with high dose combined cytokines.

Granulocyte colony stimulating factor (G-CSF) and granulocyte macrophage colony stimulating factor (GM-CSF) are cytokines which have been extensively administered as monotherapy to patients with a variety of hematopoietic disorders at dosages of 5 mcg/kg/day. Because their spectrum of activity is both singular and simultaneously overlapping, we postulated that combined therapy would be more advantageous than monotherapy. Since 1992 we have carried out a study of G-CSF and GM-CSF as monotherapy or in combination in pediatric patients with solid tumors following chemotherapy induced nadirs of 0-800 WBC/mm3. When combined, the cytokines were given twice per day at 2.5 or 5.0 mcg/kg. For the monotherapy groups, either cytokine at 5 mcg/kg or 10 mcg/kg was given once daily. The mean time to recovery from neutropenia nadir ranged from 6.6-8.2 days in patients receiving a total of 10 mcg/kg/day compared to 10.4-10.6 days in patients treated with 5 mcg/kg/day. Side effects were ephemeral eosinophilia. The dosage of 10 mcg/kg/day appears to be a better dosage for pediatric patients with a slight advantage in the combined twice a day schedule (6.6 days).