Patent ID: 7465447

Claim:
A population of purified Fc-EPO fusion proteins suitable for administration to a mammal, the Fc-EPO fusion proteins comprising an Fc portion towards the N-terminus of the Fc-EPO fusion proteins and an erythropoietin portion towards the C-terminus of the Fc-EPO fusion proteins, said population having an average of 11-28 sialic acid residues per purified Fc-EPO fusion protein, wherein the Fc portion comprises a CH2 domain derived from an IgG2 heavy chain, the CH2 domain comprising a mutation of the glycosylation site within the CH2 domain of the IgG2 heavy chain, wherein the mutation is of an asparagine within the Gln-Phe-Asn-Ser (SEQ ID NO:16) amino acid sequence within the CH2 domain of the IgG2 heavy chain.