[The use of erythropoietin beta, two to three times per week, once per week and once every other week: meta-analysis of two clinical trials].

INTRODUCTION: Renal anemia is a very common finding in patients with chronic kidney disease (CKD), both in patients not yet requiring dialysis and in patients on hemodialysis. Erythropoietin therapy is a gold standard in the treatment of renal anemia for more than 15 years. The aim of this meta-analysis was to assess the efficacy of different regimes of Recormon (erythropoietin beta, F. Hoffmann-La Roche) in maintaining stable levels of hemoglobin (Hb) and hematocrit (HCT) in patients receiving hemodialysis.

MATERIAL AND METHODS: Two multicenter open comparative three arm trials lasting for 24 weeks were conducted in Serbia and Montenegro, between 2004-2006, with a total of 216 patients from 23 hemodialysis centers (22 from Serbia and 1 from Montenegro). The inclusion criteria were as follows: stable Hb level (>100 g/l), ferritin level > 200 microg/l and transferrin saturation >20%. The patients also had to be on stable doses of Recormon, before starting the trial. A total of 203 patients finished the study according to the protocol, and their results were used for this meta-analysis. During the first 8 weeks all patients received the usual 2-3 times weekly dose of epo. 8 weeks later, 147 patients started receiveing epo once weekly, while 56 patients (group 1) continued on the 2-3 times dose during the entire study period. After another 8 weeks, 20 of those 147 patients receiving epo once weekly were transferred to once every week dose of epo (group 3), while 127 patients were on once weekly dose until the end of the trial (group 2). Primary efficacy parameter was the percentage of patients who maintained their target Hb and HCT level (>100 g/l and >30% for HB and HCT respectively).

RESULTS AND DISCUSSION: The efficacy analysis included the per-protocol population (203 patients). Hb levels remained stable (>100 g/l) in all three groups. There were no statistically signifant differences in Hb levels between the groups, with mean Hb level > 11 g/dL in all three groups throughout the study. HCT levels also remained stable (>30%) in all three groups throughout the study, without statistical significance between visits and between groups. The average epo doses were not statistically different between groups, although group 3 had-slightly higher mean Hb level than groups 1 and 2. The main tolerability parameters. sitting systolic (SSBP) and diastolic (SDBP) blood pressures were monitored at all visits. Statistical analysis showed no difference in SSBP or SDBP between the visits or groups of patients throughtout the study, although one patient had to be excluded due to uncontrolled hypertension. Only one patient (0.5%) received one blood transfusion during both studies.

CONCLUSION: All three dose regimens of subcutaneous epo beta were statistically equivalent in maintaining the target Hb and HCT levels. The use of epo once weekly or once every other week was not associated with dose increase, proving that optimization of treatment for every patient is possible in everyday clinical practice. The possibility of using 3 different dose regimes of epo beta, without compromising efficacy or increasing costs of treatment may be beneficial in the quest for better patient compliance.