Microbiological Challenge Test of Contamination Caused by Using the PhaSeal System

Abstract

In the Japanese Pharmacopoeia, there are no criteria for multiple uses, such as multidose vials, for rubber stoppers (RS), which may cause bacteriological contamination. To resolve this problem we would like to suggest the use of a closed system (CS), while considering the structure. However, multidose vials are not always kept in an aseptic environment. Hence, it is necessary to assess CS contamination and metal needles, so we compared the microbiological contamination level using Bacillus subtilis between the PhaSeal system (PS) and metal needles.On the RS of a vial containing distilled water and the top of PS-P21＇s membrane, 3.0 × 10 4 spores were prepared (＂Bacillus-vial＂ and ＂Bacillus-P21＂). An unused P21 was attached to the Bacillus-vial (Sample1). A metal needle was vertically inserted into the Bacillus-vial, and each of the puncture and vial inversion operations was carried out once, 5 times, and 10 times (Sample 2-1, 2-5, 2-10). Furthermore, Bacillus-P21 was attached to the Bacillus-vial, and PS-N35 was attached to Bacillus-P21. Each puncture was carried out once, 5 times, and 10 times (Sample 3-1, 3-5, 3-10). Viable bacterial cells were counted using the pour plate method. Bacterial cells were detected in all samples; however, bacterial cells were not detected from control vials that were not administered prepared spores. The B. sublitis contamination rates of Sample 1/2-1/2-5/2-10/3-1/3-5/3-10 were 0.7/1.4/3.1/1.9/0.1/3.2/5.0 ％, respectively. This study suggests that PS is almost equivalent to metal needles at up to 5 punctures in terms of microbiological contamination when PS is used multiple times for multidose preparation under preparation conditions where the vials are susceptible to bacterial contamination.