Hematide is immunologically distinct from erythropoietin and corrects anemia induced by antierythropoietin antibodies in a rat pure red cell aplasia model.

Objective: To evaluate the potential of Hematide, a PEGylated, synthetic peptide-based erythropoiesis-stimulating agent that is in clinical development for the treatment of anemia associated with chronic kidney disease and cancer, to correct antierythropoietin antibody-associated pure red cell aplasia (PRCA).

Materials And Methods: The binding of anti-Hematide antibodies (mouse, rabbit, and monkey) to recombinant human erythropoietin (rHuEPO) and of anti-rHuEPO antibodies (mouse, goat, rat, and human) to Hematide were evaluated. An anti-EPO antibody-mediated anemia rat model was developed by subcutaneously administering rHuEPO to rats three times weekly for 4 weeks. Sixty percent of the animals developed PRCA as characterized by severe anemia, reduced reticulocytes, anti-EPO antibodies, and limited bone marrow erythroid precursors. The effect of Hematide administration on the PRCA rats was evaluated.

Results: Antibodies to EPO do not cross react with Hematide and, conversely, antibodies to Hematide do not cross react with EPO. Hematide corrected antibody-induced anemia in a rat PRCA model.

Conclusions: The data support the potential of Hematide to correct anti-EPO antibody-associated PRCA in humans. In addition, the data suggest a negligible risk for development of anti-EPO antibody-induced PRCA secondary to Hematide administration.