Peginesatide is a synthetic peptide attached to polyethylene glycol for the treatment of anemia. The polyethylene glycol moiety helps make the drug less immunogenic and prolongs its plasma half-life. Chemically, peginesatide is designed to mimic the pharmacological activity of erythropoietin, but is not a replica of the structure itself. Peginesatide consists of two 21-amino acid chains that are covalently bonded by a linker derived from iminodiacetic acid and β-alanine.