Epoetin omega for treatment of anemia in maintenance hemodialysis patients.

After the synthesis of epoetins alpha and -beta, a third molecule of recombinant human erythropoietin (rHuEPO) was synthesized and was named epoetin-omega. The molecule of epoetin-omega is a sialoglycoprotein with smaller amounts of O-bound sugars, less acidic and with different hydrophylity than the other 2 epoetins. The purpose of the study was to assess the efficacy, safety and clinical tolerance of epoetin-omega for treatment of renal anemia. In an open-label, uncontrolled prospective clinical study, 22 end-stage renal disease patients (9 male and 13 female) were followed for 6 months. They all had a hemoglobin (Hb) value below 85 g/l, and were on regular hemodialysis therapy 3 times a week, 4 hours per session. The initial weekly dose of epoetin-omega was 90 units per kg of body weight (b.w.) divided in 3 equal portions and administered subcutaneously after each dialysis session. After correction of the hemoglobin, the dose of rHuEPO was individualized to keep Hb within target limits of 100-120 g/l. To follow efficacy and safety, a number of clinical and laboratory parameters were monitored. All patients responded well to the therapy with corrected hemoglobin after the 10th week of the study. The mean dose of epoetin-omega during the correction period never exceeded 100 U/kg b.w. per week. The average maintenance dose of rHuEPO was 50-60 U/kg b.w. per week. Iron was, where needed, supplied intravenously. We noted no change in serum urea. creatinine, phosphorus, and heparin dose per dialysis session. The prothrombin time improved during the study. Serum albumin increased. No change was observed in urea reduction ratio (URR), body weight and mean arterial pressure. One serious adverse event was noted: worsening of hypertension in 1 patient, with the development of hypertensive encephalopathy and severe headache. rHuEPO treatment was stopped. The blood pressure was effectively controlled by reducting her body weight by 5%. Thereafter, rHuEPO therapy was resumed with good blood pressure control. We could conclude that recombinant human erythropoietin-omega was an efficient and safe therapeutic agent for the treatment of renal anemia.