Long survival of leukemic mice by repeated combination treatment of cyclophosphamide and recombinant human granulocyte colony-stimulating factor

The therapeutic and hematological effects of recombinant human granulocyte colony-stimulating factor (rhG-CSF) in combination with cyclophosphamide (CY) were investigated in a murine myeloid leukemia model. Ten daily administrations of rhG-CSF following CY prolonged the survival time of leukemic mice more than either agent alone. Hematological examination indicated that this effect was attributable to suppression with rhG-CSF of the leukemic repopulation after CY injection. In addition, rhG-CSF accelerated recovery from CY-induced neutropenia