Human recombinant granulocyte macrophage colony stimulating factor (GM-CSF) treatment of patients with acute leukemias in aplasia and at high risk of early death.

In the first clinical study on GM-CSF in acute leukemias continuous infusion of the growth factor is given to patients in aplasia and at high risk of early death due to age over 65 years and/or intensive chemotherapy for resistance or relapse. Among 6 patients (4 AML, 2 ALL) receiving a total of 7 courses two died too early to contributing adequate data. Three patients and 4 courses showed earlier neutrophil recovery than related control groups and a fourth patient with secondary AML showed a neutrophil recovery time in the normal range, but much shorter than her platelet and reticulocyte recovery. No evidence was obtained so far for leukemic regrowth in these patients including blood and bone marrow cytology, monitoring of DNA aneuploidy by flow cytometry and clonogenic cells by colony assays. Thus, GM-CSF may be useful for rescue after intensive chemotherapy of AML and ALL and may not necessarily increase the risk of leukemia progression.