Busulfex®is a new type of busulfan which can be administered intravenously. Usually it is administered over 2 hours every 6 hours. Its injection should be finished within 8 hours after mixture with a saline, which may bring some troublesome in clinical practice. We, here, introduce the prefilled-syringe method; Busulfex® is filled into an injection syringe made of polypropylene beforehand under a sterile condition, and mixed with a saline just before the administration at the bed side. To evaluate the safety of this method we studied the stability of busulfan solution in the syringe physically and chemically. The drug solution was made with the same ingredients as Busulfex®, filled into a syringe, and stored at 4°C until use. Then, the transparency of this solution was studied with spectroscopy and the concentration of busulfan was analyzed directly by HPLC. Busulfan solution stored in non-colored injection syringe at 4°C was stable for up to 96 hours both physically and chemically. We concluded that prefilled-syringe method is ease and safe way to administer Busulfex® on scheduled time.
