The clinical use of hematopoietic growth factors

Recombinant DNA technology has allowed for the production of large quantities of several hematopoietic growth factors as cloned gene products. Three of these factors--recombinant human erythropoietin (r-HuEPO), granulocyte macrophage colony-stimulating factor (GM-CSF), and granulocyte colony-stimulating factor (G-CSF)--are currently undergoing clinical trials and appear to offer considerable promise for the treatment of a variety of hematopoietic abnormalities. Therapy with r-HuEPO can raise the hematocrit levels of patients with end-stage renal disease. Therapy with GM-CSF in patients undergoing marrow transplantation results in acceleration of granulocyte and platelet recovery by 1 to 2 weeks, leading to fewer infections and earlier discharge from the hospital. Other demonstrated uses of GM-CSF include treatment for aplastic anemia, myelodysplastic syndromes, chemotherapy-induced neutropenia, and neutropenia associated with the acquired immunodeficiency syndrome (AIDS). Similar beneficial effects have been reported with G-CSF. Other hematopoietic growth factors, including the interleukins (IL)-1, -3, and -6, will soon be entering clinical trials. For the first time, the availability of a large number of hematopoietic growth factors may allow physicians to regulate closely the entire hematopoietic system of their patients.