A process of purifying a Growth Factor Protein in a purification sequence employing chromatography characterized in that: - at least one chromatography is performed using a multimodal resin; - the Growth Factor Protein binds to the multimodal resin at a pH between 4 to 6.2, and the Growth Factor Protein is eluting at a pH > 6.3, and the elution of Growth Factor Protein is improved by addition of arginine and/or NaCI to the eluting buffer. - The multimodal resin step is followed by a yeast derived affinity ligand resin step, which results of a purity of the product >90%.