Clinical use of hematopoietic growth factors.

With the identification of recombinant production of the hematopoietic growth factors, these cytokines have been evaluated in the treatment of primary bone marrow failure states and after myelosuppressive chemo- or radiotherapy. Granulocyte colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, and erythropoietin have been approved for clinical use, and others including c-mpl-ligand (also called megakaryocyte growth and development factor or thrombopoietin) are in phase I and II trials. Most studies have been done with granulocyte and granulocyte-macrophage colony-stimulating factors; their beneficial effects are proven regarding acceleration of granulocyte recovery after chemo- and radiotherapy. In the majority of trials, this acceleration results in a reduction of infectious risks, a shortening of drug- and radiation-induced myelosuppression, and a higher chemotherapy dose intensity; however, an improved remission rate and improved long-term survival rates have not yet been definitively documented. Guidelines have been published to provide a rational basis for the use of these factors in clinical practice. It should be emphasized, however, that for many of the recommendations data from randomized clinical trials are lacking.