腎臓学と治療学ジャーナル

Treatment of Renal Anemia in Saudi Dialysis Patients: Between Darbepoetin Alfa and Recombinant Human Eryhthrpoietin (rHuEPO)

Abstract

Abdullah Khalaf Al-Hwiesh, Ibrahiem Saeed Abdul-Rahman

Background: Darbepoetin alfa is an erythopoietic agent with a 3-fold longer elimination half-life than recombinant human erythropoietin (rHuEPO), which allows less frequent dosing, and hence it maintains an effective hemoglobin control at extended dose intervals compared with rHuEPO. This study assessed the efficacy and safety of unit doses of darbepoetin alfa for the treatment of renal anemia in hemodialysis (HD) and peritoneal dialysis (PD) patients. Methods: In this prospective study, 143 dialysis patients (68 HD and 75 PD patients) maintained on stable rHuEpo treatment were switched to darbepoetin alfa at extended dose intervals by the same route of administration as previous rHuEpo therapy [intravenous (i.v.), n=78 or subcutaneous (s.c.), n= 65]. Patients receiving rHuEpo two or three times a week were switched to darbepoetin alfa once a week and those receiving rHuEpo once a week were switched to darbepoetin alfa once every two weeks. The unit doses of darbepoetin alfa (10-150 ug) were titrated to maintain hemoglobin concentrations of 10-12 g/dl for 24 weeks. Results: Hemoglobin (Hgb) concentrations were maintained effectively in our patients regardless of the dose interval of darbepoetin alfa. The overall mean change in Hgb concentration from baseline to evaluation period was an increase of 0.18 g/dl (95% CI ± 0.16). Regardless of route of administration, darbepoetin alfa effectively maintained mean Hgb concentration above 11 g/dl throughout the entire study period. Darbepoetin alfa administered by both the i.v. and s.c. routes resulted in stable mean Hgb concentrations during the evaluation period. Subjects with baseline Hgb concentrations < 11 g/dl experienced significant mean increase in Hgb concentration from baseline to evaluation, which was more pronounced following i.v. than s.c. administration (0.79 vs o.55 g/dl respectively). Relative to baseline, i.v. and s.c. darbepoetin alfa dosage requirements decreased in subjects with baseline Hgb ≥11g/dl (21.64 to 15.86 ug/week and 21.95 to 18.52 ug/week respectively p =0.0214), while there was a little increase in darbepoetin alfa dosage in subjects with baseline Hgb < 11 g/dl (25.22 to 26.76 ug/week and 22.74 to 24.81 ug/week in the i.v. and s.c. groups respectively p=0.0581). The percentage change in dose requirements from baseline to evaluation period in all patients, regardless of route of administration was not significant (2.28%, 95% CI -3.64, 7.89). Hemoglobin concentrations were also effectively maintained in patients who received darbepoetin alfa once weekly and once every other week. Darbepoetin alfa was well tolerated in all HD and PD patients, and the safety profile was consistent with previous trials with darbepoetin alfa in dialysis patients. Conclusion: The treatment of renal anemia in dialysis patients (both HD and PD) with unit doses of darbepoetin alfa is both effective and well tolerated. Moreover, administration of darbepoetin alfa by both i.v. and s.c. route is associated with stable Hgb concentration. Darbepoetin alfa administered i.v. or s.c once weekly or once every other week is an effective and safe treatment regimen for hemodialysis and peritoneal dialysis patients with renal anemia.