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.