The efficacy of epoetin alfa (recombinant human erythropoietin) has been tested for treating the anemia associated with end‐stage renal disease. This anemia is caused by severely decreased levels of erythropoietin, 90% of which is ordinarily produced by healthy kidneys. Treatment with epoetin alfa successfully corrected the anemia of 97% of 333 patients, as evidenced by hematocrit levels that increased by at least 6 percentage points or reached a study target level of 35%, 2 points above current guidelines. The 127 patients who previously required red cell transfusions to maintain an adequate hematocrit became completely transfusion independent after receiving epoetin alfa. Furthermore, treatment with this growth factor alleviated many of the symptoms of uremia, such as loss of energy and appetite. The major side effect observed with epoetin alfa treatment was increased diastolic blood pressure; however, this was well controlled by additional antihypertension medication. There have been no reports of antibody formation in response to this drug. Thus, epoetin alfa is a safe and effective means of treating the anemia caused by chronic renal insufficienc