Erythropoietin (or EPO) is a glycoprotein hormone produced in the human kidney and also produced in the liver, the brain and uterus. Erythropoietin production is stimulated by the reduction of oxygen in the renal arteries.
It acts by binding to the specific erythropoietin receptor. Erythropoietin stimulates stem cells in the bone marrow to increase production of erythrocytes.
Patients with renal failure have low levels of erythropoietin which in turn leads to the chronic anemia that accompanies renal failure. The use of recombinant EPO has essentially eliminated anemia as a major cause of morbidity in dialysis patients.
The clinical development of recombinant products posed challenges, heretofore not present with conventional pharmaceutical products.