Study on Safety of Reusing the Residual Drug Solution in a Single-dose Vial at the Time of Needle Puncture

Abstract

We studied safety in terms of the drug storage-requirement, preparation procedure and use of closed system transfer devices (CSTD) for reusing the residual drug solution in a single-dose vial, which was based on the presupposition that cleaning with ethanol was performed before reuse. Bacillus subtilis was applied to a rubber stopper on a simulated vial or to three types of CSTD connected to the vial and allowed to stand for 24 or 48 hours. After 6 times of wiping, punctured with 18G needle or CSTD. As a result of culturing, bacteria were detected in all groups.

Therefore, Bacillus subtilis was separately applied to a rubber stopper of the same simulated vial separately, and after wiping, bacteria remaining on the rubber stopper were cultured and counted. Contamination was detected in about 1/10 of the coating amount. It is suggested that complete removal of bacteria, which is expected to have a disinfection effect, is difficult by wiping alone and microorganisms adhering to the rubber stopper may contaminate the vial at the time of puncture. It was confirmed that when reusing the residual drug solution in a single-dose vial, microbial contamination into the vial can occur if the puncture site of the vial is not kept clean, regardless of whether or not CSTD is used. In the case of storing in an environment where microbial contamination can occur, it is necessary to consider a method by which bacteria can be completely removed.