Abstract
Epoetin beta pegol is a novel agent that corrects anemia and raises hemoglobin (Hb) levels when administered at monthly intervals. However, patients undergoing therapy with epoetin beta pegol demonstrate a monthly variability of Hb levels; Hb levels increase and reach a peak 2 weeks after the injection, and decrease and reach a trough 4 weeks after administration. Studies suggest that rapid variability of Hb, especially a rapid fall in the Hb level, contributes to a risk of cardiovascular events. It is, therefore, important to understand the characteristics of patients showing marked monthly variability of Hb levels associated with epoetin beta pegol therapy. We defined the “high-variability group” as patients in whom the Hb difference from the peak-to-trough levels was more than 0.7 g/dL two times, and the rest of the patients fell into the “low-variability group.” Fifty-eight dialysis patients who received therapy with epoetin beta pegol once every 4 weeks were evaluated. Sixteen patients were in the high-variability group, and 39 patients were in the low-variability group. The low-variability group showed maintained Hb levels, but the high-variability group showed decreased Hb levels (low-variability group: Hb, 11.43±1.90 g/dL; high-variability group: Hb, 10.19±1.45 g/dL; p=0.002). The high-variability group showed significantly higher levels of transferring saturation (TSAT) than the low-variability group (p=0.042). Moreover, patients with elevated Hb levels in the low-variability group were defined as an “Hb-elevated group.” The high-variability group showed significantly higher levels of Fe (p=0.025) and TSAT (p=0.043) and significantly lower levels of serum ferritin (p=0.009) than the Hb-elevated group. Dialysis patients who have adequate functional iron and poor iron storage are likely to exhibit marked monthly variability on treatment with epoetin beta pegol. In order to suppress the monthly variability of Hb, patients who have low levels of serum ferritin may be administered iron.
