#1171 Effect of methoxy polyethylene glycol-epoetin beta on delaying dialysis in anemic patients with Stage 4-5 chronic kidney disease
Authors: Phannajit Jeerath , Takkavatakarn Kullaya , Wuttiputhanun Thunyatorn , Katavetin Pisut , Eiam-Ong Somchai , Susantitaphong Paweena , Praditpornsilpa Kearkiat 
Published: May 2024

Abstract

Background and Aims
The optimal hemoglobin (Hb) target for treating anemia in pre-dialysis chronic kidney disease (CKD) remains controversial. This study investigates the efficacy and safety of methoxy polyethylene glycol-epoetin beta, in delaying the initiation of kidney replacement therapy (KRT), all-cause mortality, CKD progression, and quality of life in stage 4-5 CKD patients. It compares outcomes between patients targeting an Hb level of 10.5-11.5 g/dL versus 8.5-9.5 g/dL.

Method
This was a single-center, open-label, parallel-group randomized controlled trial. Patients with estimated glomerular filtration rates (eGFR) of 8-15 ml/min/1.73 m2, who had not yet started dialysis, were randomized into two groups based on different Hb targets (Group A: 10.5-11.5 g/dL, Group B: 8.5-9.5 g/dL). Methoxy polyethylene glycol-epoetin beta (MIRCERA®) was prescribed by a pre-specified protocol to achieve these Hb targets. Iron supplements were administered to maintain transferrin saturation &gt;20% or serum ferritin &gt;200 ng/ml. Primary outcomes included a composite of all-cause death and KRT initiation, with secondary outcomes encompassing eGFR slope, hospitalization incidence, blood transfusion necessity, and quality of life measured by the 36-Item Short Form Health Survey (SF-36).

Results
A total of 62 participants were randomized. The mean age was 64.0 years (SD ±16.0), with 51.6% being female. The mean estimated Glomerular Filtration Rate (eGFR) at enrollment was 12.1 ml/min/1.73 m2 (SD ±3.1). Group A had a significantly higher time-averaged Hemoglobin (Hb) level (10.5 g/dL, SD ±1.2) compared to 8.5 g/dL (SD ±0.9) in the control group (p &lt; 0.001). There was no significant difference in the composite endpoint of all-cause death and Kidney Replacement Therapy (KRT) initiation between the two groups (Hazard Ratio [HR] 0.69; 95% Confidence Interval [CI] 0.32-1.50; p = 0.35, as shown in the Figure). The eGFR slope was similar in both groups (−2.54 vs. −2.53 ml/min/1.73 m2 per year, p = 0.9). Time-averaged ferritin, transferrin saturation, blood pressure, and dietary sodium/protein intake showed no significant differences. Participants in the lower Hb target group required more blood transfusions (11 vs 1 unit, Incidence Rate Ratio [IRR] = 0.075, 95% CI 0.002-0.517, p = 0.001). Rates of hospital admissions, and changes in SF-36 quality of life domains were comparable between the groups, as detailed in the Table.

Conclusion
The study indicates that using methoxy polyethylene glycol-epoetin beta to maintain a higher Hb target in anemic patients with stage 4-5 CKD does not significantly alter the rate of all-cause mortality, the initiation of KRT, and rate of eGFR decline compared to a lower Hb target. However, a higher Hb target may reduce the need for blood transfusions without adversely affecting the progression of CKD, hospitalization rates, or quality of life. These findings suggest that while higher Hb targets may not dramatically alter key clinical outcomes, they could offer benefits in reducing transfusion requirements, thus providing a more nuanced approach to managing anemia in late-stage CKD.