In Dec. 1985, the first clinical tests were held at the University of Washington of erythropoietin (EPO), the first blood growth factor manufactured through recombinant DNA, to correct anemia of kidney failure.

Dr. Joseph Eschbach led a clinical trial at the Northwest Kidney Centers that studied whether an artificial erythropoietin hormone, Epogen, manufactured by Amgen, could replace or supplement the naturally occurring hormone. The trial was successful, and the results were published in The New England Journal of Medicine in 1987. 

Most dialysis patients are anemic because their diseased kidneys make very little EPO, thus injections of EPO treat this anemia and improve patient well being and quality of life. The Federal Food and Drug Administration approved the use of EPO in June 1989.