Background: The recombinant human epoetin-a HX575 (Sandoz Pharmaceuticals GmbH/Hexal AG, Holzkirchen, Germany) is the first biosimilar erythropoiesis-stimulating agent (ESA) with marketing authorization in Europe. The primary objective of the study was the evaluation of therapeutic equivalence in terms of hemoglobin (Hb) response of HX575 compared with the comparator product (EPREX/ ERYPO, Janssen-Cilag/Ortho Biotech, Neuss, Germany) in the long-term intravenous (i.v.) treatment of anemia in chronic renal failure patients on hemodialysis following a 1 : 1 dose conversion from the comparator product to HX575.
Methods: Hemodialysis patients with Hb levels of 10.0 - 13.0 g/dl were randomized to either continue their current i.v. epoetin-a treatment or switch to HX575. During treatment, epoetin dosages were titrated to maintain Hb values. The primary endpoint was the difference between treatment groups in the mean absolute change of Hb levels between baseline and evaluation period (Weeks 25 - 28).
Results: Therapeutic equivalence of HX575 and the comparator epoetin-alpha, assessed during the evaluation period, was statistically confirmed: mean changes in Hb levels were 0.15 +/- 0.09 g/dl in the HX575 and 0.06 +/- 0.12 g/dl in the comparator epoetin-a group, with a difference between groups of 0.08 g/dl (95% confidence interval: -0.17; 0.34). Hb levels and epoetin dosages remained stable throughout the entire study period of 56 weeks. The long-term safety profile of HX575 was similar to that of the comparator epoetin-alpha. No antibody formation was detected.
Conclusions: The study demonstrated therapeutic equivalence of biosimilar HX575 to the comparator epoetin-a, together with a comparable safety profile.