Focus on Bioburden Culture Media and Medical Devices.

Medical devices are a vital part of the global health care system that can have a far-reaching impact on patient treatment. Therefore, they must be sterile to ensure patient safety. The prevalent microorganism's type on a medical device, also known as "bioburden", is a useful indicator of a potential contamination source. Indeed, bioburden is a potential risk to the patient not only because the sterilization process might not be completely effective, but also post-processing because of the possible presence of residual materials. Although bioburden may be confidently killed by destructive sterilization processes, its proliferation before sterilization should be avoided. For the bioburden determination, the culture media and incubation conditions must be carefully selected. The culture medium is of fundamental importance for most microbiological tests: to obtain pure cultures, to grow and count microbial cells, and to cultivate and select microorganisms. A culture medium is essentially composed of basic elements (water, nutrients) to which must be added different growth factors that will be specific to each bacterium and necessary for their growth. Without high-quality media, the possibility of achieving accurate, reproducible, and repeatable microbiological test results is reduced. In ISO 11737-1:2018 "Sterilization of Health Care Products-Microbiological Methods-Part 1: Determination of a Population of Microorganisms on Products", methods for the determination and microbial characterization of bioburden are proposed. However, few guidelines are given as to culture media other than examples and incubation times. Several studies show that other culture media can also be effective, such as Plate Count Agar (PCA). The purpose of this review was to focus on parameters that can have an impact on the bioburden evaluation, specifically the culture medium type for the microorganisms' detection on medical devices. Experimentations conducted in our laboratories showed that PCA appeared to be a medium of primary importance for the detection of bioburden on medical devices; this medium also respects the 3Rs rule.

Filaire E ，Rochette V ，Jarousse E ，Poinsot C ... -  《-》

Increasing Patient Safety by Closing the Sterile Production Gap-Part 3-Moist Heat Resistance of Bioburden.

Terminal sterilization is considered the preferred means for the production of sterile drug products, as it affords enhanced safety for the patient because the formulation is sterilized in its sealed, final container. Despite the obvious patient benefits, the use of terminal sterilization is artificially constrained by unreasonable expectations for the minimum time-temperature process to be used. The core misunderstanding with terminal sterilization is the notion that destruction of a high population of a resistant biological indicator microorganism is required. More contemporary thinking on sterilization acknowledges that the bioburden is the actual target in sterilization and its destruction must be assured. In the application of low-temperature moist heat for terminal sterilization, especially subsequent to aseptic processing, establishing the pre-sterilization bioburden to consider has proven challenging. Environmental monitoring survey data has determined the identity of potential microorganisms but not their resistance to sterilization. This review article provides information on the moist heat resistance of vegetative and sporeforming microorganisms that might be present. The first paper in this series provided the overall background and described the benefits to patient, producer, and regulator of low-temperature moist heat for terminal sterilization. The second paper outlined validation and operational advice that can be used in the implementation. This final effort concludes the series and provides insight into potential bioburden and its resistance.LAY ABSTRACT: Terminal sterilization is considered the preferred means for the production of sterile drug products as it affords enhanced safety for the patient as the formulation is filled into its final container, sealed and sterilized. Despite the obvious patient benefits, the use of terminal sterilization is artificially constrained by unreasonable expectations for the minimum time-temperature process to be used. The primary consideration in terminal sterilization is the reliable destruction of the bioburden. The earlier manuscripts in this series described the principles and implementation of low temperature terminal sterilization processes where the sterilization conditions would destroy the expected bioburden present. To accomplish that reliably knowledge of the bioburden expected resistance to moist heat is necessary. This review article will identify publications where that data can be found.

Agalloco JP 《-》

A comparison of incubation periods for bioburden isolates.

Bryans T ，Alexander K 《-》

Validation of Milliflex(®) Quantum for Bioburden Testing of Pharmaceutical Products.

This article reports the validation strategy used to demonstrate that the Milliflex® Quantum yielded non-inferior results to the traditional bioburden method. It was validated according to USP <1223>, European Pharmacopoeia 5.1.6, and Parenteral Drug Association Technical Report No. 33 and comprised the validation parameters robustness, ruggedness, repeatability, specificity, limit of detection and quantification, accuracy, precision, linearity, range, and equivalence in routine operation. For the validation, a combination of pharmacopeial ATCC strains as well as a broad selection of in-house isolates were used. In-house isolates were used in stressed state. Results were statistically evaluated regarding the pharmacopeial acceptance criterion of ≥70% recovery compared to the traditional method. Post-hoc test power calculations verified the appropriateness of the used sample size to detect such a difference. Furthermore, equivalence tests verified non-inferiority of the rapid method as compared to the traditional method. In conclusion, the rapid bioburden on basis of the Milliflex® Quantum was successfully validated as alternative method to the traditional bioburden test.LAY ABSTRACT: Pharmaceutical drug products must fulfill specified quality criteria regarding their microbial content in order to ensure patient safety. Drugs that are delivered into the body via injection, infusion, or implantation must be sterile (i.e., devoid of living microorganisms). Bioburden testing measures the levels of microbes present in the bulk solution of a drug before sterilization, and thus it provides important information for manufacturing a safe product. In general, bioburden testing has to be performed using the methods described in the pharmacopoeias (membrane filtration or plate count). These methods are well established and validated regarding their effectiveness; however, the incubation time required to visually identify microbial colonies is long. Thus, alternative methods that detect microbial contamination faster will improve control over the manufacturing process and speed up product release. Before alternative methods may be used, they must undergo a side-by-side comparison with pharmacopeial methods. In this comparison, referred to as validation, it must be shown in a statistically verified manner that the effectiveness of the alternative method is at least equivalent to that of the pharmacopeial methods. Here we describe the successful validation of an alternative bioburden testing method based on fluorescent staining of growing microorganisms applying the Milliflex® Quantum system by MilliporeSigma.

Gordon O ，Goverde M ，Staerk A ，Roesti D ... -  《-》

Quantitative and qualitative evaluation of microorganism profile identified in bioburden analysis in a biopharmaceutical facility in Brazil: Criteria for classification and management of results.

Mattoso JMV ，Costa LV ，Vale BA ，Reis CMF ，Andrade JM ，Braga LMPS ，Conceição GMS ，Costa PBM ，Silva IB ，Rodrigues LAP ，Anjos JP ，Brandão MLL ... -  《-》