Pharmacodynamic model of Hepcidin regulation of iron homeostasis in Cynomolgus monkeys

Hepcidin (H25) is a hormone peptide synthesized by the liver that binds to ferroportin and blocks iron export. In this study, H25 was inhibited by administration of single and multiple doses of an anti-H25 monoclonal antibody Ab 12B9m in cynomolgus monkeys. The objective of this analysis was to develop a pharmacodynamic model describing the role of H25 in regulating iron homeostasis and the impact of hepcidin inhibition by Ab 12B9m. Total serum H25 and Ab 12B9m were determined in each animal. Corresponding measurements of serum iron and hemoglobin (Hb) were obtained. The PD model consisted of iron pools in serum (FeS), reticuloendothelial macrophages (FeM), hemoglobin (FeHb), and liver (FeL). The iron was assumed to be transported between the FeS, FeHb, and FeM unidirectionally at rates kS, kHb, and kM. H25 serum concentrations were described by the previously developed PK model with the parameters fixed at their estimates.