Liposome-Encapsulated Hemoglobin as an Artificial Oxygen Carrier: Technological Features, Manufacturing and Issues for Practical Application

While the use of liposome-encapsulated hemoglobin (LEH) as artificial oxygen carriers (AOCs) has long been studied, its complicated manufacturing process and large production costs have hindered the progress in its development and, subsequently, its advancement to practical applications. However, we have been persistently developing LEH as an analogue of red blood cells (RBCs) for its use as AOCs, and to this end we have constructed a Good Manufacturing Practice (GMP) facility where LEH can be manufactured as biologics under quality assurance systems as well as establishing the manufacturing processes of LEH at this facility. We have also clarified the physicochemical properties and stability of LEH, and further confirmed the fundamental efficacy and safety of LEH as AOCs. Although the technology of LEH has already reached the stage of clinical testing, its high manufacturing costs remains an unsolved issue if LEH is to be used as a medicinal product.