Renal
anemia is predominantly caused by a relative deficiency in
erythropoietin (EPO). Conventional treatment for renal
anemia includes the use of recombinant human EPO (rhEPO) or a long-acting erythropoiesis-activating agent named
darbepoetin alfa, which is a modified rhEPO with a
carbohydrate chain structure that differs from native hEPO. We have developed a
biosimilar to
darbepoetin alfa designated JR-131. Here, we comprehensively compare the physicochemical and
biological characteristics of JR-131 to
darbepoetin alfa. JR-131 demonstrated similar
protein structure to the originator,
darbepoetin alfa, by
peptide mapping and circular dichroism spectroscopy. Additionally, mass spectroscopic analyses and capillary zone electrophoresis revealed similar glycosylation patterns between the two products. Human bone marrow-derived erythroblasts differentiated and proliferated to form colonies with JR-131 to a similar degree as
darbepoetin alfa. Finally, JR-131 stimulated erythropoiesis and improved
anemia in rats similarly to
darbepoetin alfa. Our data show the similarity in physicochemical and
biological properties of JR-131 to those of
darbepoetin alfa, and JR-131 therefore represents a
biosimilar for use in the treatment of renal
anemia.