The development of recombinant human serum albumin.

We have developed a fermentation process for recombinant human serum albumin (rHSA) production using an expression strain of the methylotrophic yeast Pichia pastoris. The high productivity of the process enables it to compete with the production of plasma derived HSA. After purification of the rHSA, the content of yeast derived contaminants was less than 1 ng/250 mg of rHSA. The results from structural analyses suggested that purified rHSA possessed an identical conformation to plasma derived HSA. Furthermore, no neoantigenicity different from that of plasma derived HSA was observed. The efficacy and safety of rHSA were tested in clinical studies, and it was shown that there was no difference between rHSA and plasma derived HSA in a comparison study. The high efficacy of rHSA with little or no adverse reaction was confirmed in these studies.