Patent ID: 8431132

Claim:
A method of stimulating erythropoiesis in a mammal comprising administering to said mammal a fusion protein comprising: (a) a naturally occurring human erythropoietin molecule having a cysteine residue proximate to a C terminal thereof; and (b) a human IgG Fc fragment comprising a hinge region, wherein an N terminal of said hinge region is directly linked to said C terminal of said erythropoietin molecule and wherein said hinge region comprises a mutation whereby a cysteine residue of said hinge region located nearest said N terminal is substituted with a non-cysteine residue, whereby the first cysteine residue of said hinge region nearest said N terminal is spaced at least 17 amino acids apart from said cysteine residue of said erythropoietin residue, wherein said protein has an in vivo erthryopoietic potency and half-life at least equal to native human erythropoietin and wherein said protein has the amino acid sequence present in SEQ ID NO:2 or a sequence having at least 90% sequence identity thereto.