G-CSF製剤 (ナルトグラスチム) の持続注入時におけるシリンジへの吸着とその対策

We studied the adsorption of nartograstim (NT), a recombinant human granulocyte colony-stimulating factor, to a 20mL plastic syringe made of polypropylene, and the actual dose of NT through an extension tube and infusion set from a syringe filled NT solution. Furthermore, the effect of the addition of a vitamin injection containing polysorbate surfactants for IVH on the adsorption of NT as a method to prevent NT adsorption, was investigated. The residual rate of NT in 20mL solution just after filling the syringe decreased in proportion as to the lower the NT concentration added in the range of 0.2μg/mL to 5μg/mL. The value in 0.2μg/mL was the lowest and about 70%. Thereafter, the residual rate to time in the case of concentrations under 2.5μg/mL, declined gradually. The values at 6h after filling the syringe were 55% (2.5μg/mL), 45% (1μg/mL) and 30% (0.2μg/mL). When a 20mL solution containing 2.5μg/mL of NT in a syringe was infused through an extension tube and infusion set using a syringe pump at the infusion rate of 0.33mL/min, the actual NT administered was estimated to be about half of the NT added initially. This result means that the actual intravenous (i.v.) dose of NT was almost the same as the subcutaneous (s.c.) dose due to the fact that the i.v. dose is twice to s.c. in the description of the package insert of nartograstim (Neu-up®). This adsorption of NT to syringe and administration set was almost completely prevented by adding vitamin injection for IVH to NT solution. Furthermore, the actual dose of NT recovered from 51.6%to 85.5% of die theoretical dose. However, when the vitamin injection for IVH was added to the NT solution for the prevention of the NT adsorption, the adjustment of the NT dose should be necessary for optical therapy. In conclusion, the above findings suggest that this method was effective for the prevention of NT adsorption to a plastic syringe and the administration set, however, this method has not yet been authorized by the Ministry of Health, Labour and Welfare.