Dose equivalency and efficacy of biosimilar erythropoietin stimulating agents: Data from real clinical practice

Recently, biosimilar erythropoietin stimulating agents become available in Kazakhstan. Important properties of the biosimilar such as dose equivalency to the original medicine (originator) and the ability to maintain hemoglobin target levels remain insufficiently described in many clinical settings. Thus, the current study aims to determine dose equivalency and hemoglobin target levels in a cohort of dialysis patients who were switched from the originator to biosimilar. Retrospective data of 74 patients from different dialysis centers who received at least 6 months of originator and switched to biosimilar and had at least 6 months follow-up were analyzed. The clinical data of 32 male and 42 female patients were collected. The mean age was 52.5 ± 13.5 years. There is no significant difference in mean levels of hemoglobin during pre-switching from originator to biosimilar (6 months prior) and post switching period (9 months after). Additionally, a subgroup analysis of 59 patients who received originator (epoetin beta), 6 months before the switch, showed similar level of hemoglobin (110.7 ± 14 vs 113.2 ± 10 g/L, P = .05) 6 months after the switch to biosimilar (epoetin zeta) at the equivalent dose regimen (69.5 ± 29 vs 68.1 ± 30 IU/kg/wk, P = .55). However, after 9 months of switching, patients using lower doses of biosimilar (69.5 ± 29 vs 63.3 ± 30 IU/kg/wk, P < .01), showed significantly higher levels of hemoglobin (110.7 ± 14 vs 114.7 ± 8 g/L, P = .01) compared to preswitching period. In conclusion, long-term use of lower doses of biosimilar managed to maintain hemoglobin within the target levels.