METHODS FOR PURIFYING ERYTHROPOIETIN ANALOGS HAVING LOWER ISOELECTRIC POINT

摘要

The present invention relates to a method for purifying an erythropoietin analog having a low isoelectric point below 4 by adding an N-linked sugar chain with high purity. In accordance with the present invention, the erythropoietin analog having an isoelectric point below 4, which is an isoform having more sialic acid residues, can be effectively purified via three-step chromatographic processes in short time at lower cost.