PHARMACOKINETICS OF EPOETIN (RECOMBINANT-HUMAN-ERYTHROPOIETIN) AFTER LONG-TERM THERAPY IN PATIENTS UNDERGOING HEMODIALYSIS AND HEMOFILTRATION

After long term therapy with epoetin (recombinant human erythropoietin ) 17 patients with end-stage renal disease (ESRD) were studied in 3 gr oups to assess pharmacokinetics during the intertreatment interval and during haemofiltration and dialysis treatment. Epoetin was measured b y radioimmunoassay. After an intravenous bolus of epoetin 150 U/kg bod yweight, the half-life was 7.7h, steady-state volume of distribution w as 0.066 L/kg and total plasma clearance was 5.4 ml/min. The mean stea dy-state serum concentration during multiple-dose administration was 6 56 U/L The drug was not eliminated by haemofiltration or dialysis. Lon g term treatment of ESRD patients with epoetin does not significantly alter the pharmacokinetic profile of the drug. Epoetin dosage adjustme nt or substitution after haemofiltration and dialysis is not necessary .