[Possible new indications for erythropoietin therapy]

The use of hematopoietic growth factors has increased rapidly during the last decade. Among the growth factors available, erythropoietin (EPO) was the first growth factor to be used clinically. To date, EPO has shown activity in the treatment of the tumor-associated anemia and for correction of tumor hypoxia, however, when compared with transfusion of erythrocytes EPO treatment did not significantly prolong survival in cancer patients in any published study so far. Recently, novel extramedullary EPO receptors have been identified leading to a better understanding of the molecular mechanisms of action of EPO. Results from these experiments and from several clinical studies suggest that EPO treatment may be beneficial for patients with (chronic) infections (HIV, inflammatory bowel disease, septic episodes) and for treatment of the fatigue syndrome following cancer chemotherapy. In addition, EPO may also improve stem cell engraftment following high-dose chemotherapy and can increase survival rates of patients with aplastic anemia and myelodysplastic syndrome. Currently, new EPO derivatives, synthetic fusion proteins and gene therapeutic studies are under clinical investigation suggesting that the EPO-induced effects may be increased significantly by these agents in the future.