Hematopoietic responses in patients with advanced malignancy treated with recombinant human granulocyte-macrophage colony-stimulating factor.

The in vivo effect of yeast-derived recombinant human granulocyte-macrophage colony-stimulating factor (rh GM-CSF) was investigated in 30 patients with advanced malignancy in a phase Ib trial. Patients were treated at four different dose levels (120 to 1,000 micrograms/m2/d) by either daily intravenous (IV) bolus injection or 24-hour continuous infusion. Administration of rh GM-CSF resulted in a broad spectrum of dose- and schedule-dependent hematopoietic effects. Sustained infusion of rh GM-CSF elicited a maximum 17-fold average peak increase of the total WBC count with mainly neutrophils, eosinophils, and monocytes accounting for this rise, and increases in bone marrow cellularity with a…