Preliminary study for a microbiological stability study: Microbiological integrity test

Background
In our hospital, the production of chemotherapy has increased by more than 20% over the last three years. To optimise our preparation time and reduce patients waiting time we would like to anticipate any preparations. In the order to demontrate in the end the sterility of our polypropylene syringes we’ll wish to realise a preliminary microbiological integrity study of our final assembly.

Purpose
Qualification of the microbiological stability in our final assembly.

Matérials and Méthods
We set up our study plan to follow the guidelines (European Pharmacopoeia (Ph. Eur.) 10th edition, chapter 2.6.1 sterility, test for sterility of the product to be examinated). In standard production conditions (sterile environment, class A isolator), we fill 24 polypropylene syringes with a 5% glucose solution (worst case) which we close with a safety Luer connector. We stock our final assemblies half at room temperature and half between +2°C and +8°C in our chemotherapy production area, before inoculate of bacterial growth media. We inoculate these bacterial growth media (soya-bean casein digest medium and fluid thioglycollate medium) with our preparations in sterile environment on Day 0 (with the positive and negative controls), D2, D7, D14, D21 and D28 (according to the Ph.Eur.). We incubate the inoculate media in hygiene laboratory to 20-25°C and 30-35°C.

Résults
We observe the absence of a bacterial growth 15 days after the beginning of incubation. Fertility test is positive in 24 hours and sterility test stay negative after 43 days of incubation so we can validate the method. That allow us to conclude to microbiological integrity of our polypropylene syringes after handling is valid for 28 days.

Conclusion and Perspectives
With these results, we will be able to devote time to realize Media Fill Test (MFT). Media Fill Test will specify our results to follow the Gerpac guidelines (May 2020). Depending on the results, we may anticipate preparations in this final assembly, such as subcutaneous doses of trastuzumab

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