Clarifications on the Intended Use of USP <61> Microbiological Examination of Nonsterile Products: Microbial Enumeration Tests.

In the execution of its legislated responsibilities, the United States Food and Drug Administration commonly refers to standard test methods detailed in the United States Pharmacopeia (USP). Microbiological test methods (contained in general chapters) are listed in chapters <51> to <80> with details regarded as enforceable where referenced as a test method. USP <61> "Microbiological Examination of Nonsterile Products: Microbial Enumeration Tests" is a globally harmonized chapter that has been successfully employed for the enumeration of microorganisms recoverable from nonsterile finished drug products. The content of USP <61> is not always scientifically principled nor emphatically understood by all pharmaceutical microbiologists. Consequently, misunderstanding and misapplication of USP <61> may result in analyses and assessments of microbiological quality that are flawed or erroneous. In this article, clarification is provided to assist the pharmaceutical microbiologist in the appropriate and intended use of USP <61>, including provision of details not always commonly known or understood.

A Nontrivial Analysis of Patient Safety Risk from Parenteral Drug- and Medical Device-Borne Endotoxin.

BACKGROUND: A thorough and systematic analysis of potential endotoxin-related safety issues from parenteral drugs and devices is important to ensure appropriate current Good Manufacturing Practices, compendial requirements, standards and regulatory guidance. Lately, the US Food and Drug Administration has been expecting pharmaceutical firms to apply an arbitrary safety factor to compendial compliant drug specifications for endotoxin, potentially causing manufacturing challenges, supply issues and additional unwarranted costs. OBJECTIVE: The aim of this study was to evaluate data from three disparate sources over an extended period of time, from 2008 to 2021, to determine if there exists an industry-wide risk to patients from parenteral drugs and devices, thereby evaluating if changes to current Good Manufacturing Practices or compendial requirements are indeed warranted. Food and Drug Administration data from current Good Manufacturing Practices non-compliance observations, product recalls and the FDA Adverse Event Reporting System were used as the three sources of data. METHODS: Parenteral products were separated into drugs and devices, potential endotoxin-related patient safety issues were characterised in terms of the available non-compliance information, the type and number of product recalls, and the type and number of potential adverse events. Descriptive statistics in Microsoft Excel 2019 and Pivot tables were used for the analysis and presentation of the data. RESULTS: From 2011 to 2021, a total of 188 endotoxin-related current Good Manufacturing Practices compliance observations were recorded, 70% and 30% were associated with laboratory and manufacturing origins, respectively. Finished drug product testing accounted for 56% of these. In contrast, 95% of all endotoxin-related product recalls were associated solely with medical devices. Over the years 2008-2021, approximately 1.4% of all adverse events (23,663,780) were recorded with some reference to pyrexia (fever); however, there are sparse data categorically attributing this to the administration of parenteral drugs or devices or combinations of these possessing high levels of endotoxin. CONCLUSIONS: Analysis of data concerning drug- and device-borne endotoxin obtained from FDA data from current Good Manufacturing Practices non-compliance observations, product recalls and the FDA Adverse Event Reporting System demonstrated the absence of industry-wide issues with endotoxin contamination. Based upon these data, changes to current Good Manufacturing Practices and the compendial methodology of setting endotoxin specifications (and hence the compendial methodology of testing for endotoxins) are unwarranted.

Sterility Assurance-Current and Future State.

Manufacture by aseptic processing accompanied by end product compendial sterility testing has been the predominant means of production and disposition of therapeutics requiring the critical quality attribute of sterility. Despite significant advancements in microbiology and epidemiology and innovations in therapeutic products and engineering, there have been minimal advancements in the standards and regulations governing the assurance of sterility. Furthermore, the assurance of sterility of current and future therapies are not well served in a singular fashion, rather therapies occupy optimal locations in a sterility assurance design space within which parametric release is the default and expected mode of product disposition. Indeed, recent chimeric antigen receptor T-cell therapies (CART) for all intents and purposes conform to the principles and requirements for parametric release; its disposition is parametric in all but words. This article offers a new direction including a "road map" for the future of sterility assurance paved through a sequence of ongoing changes to the United States Pharmacopeia (USP) informational chapters. The future state of design-space provides optimal assurance of sterility and expanded opportunities for parametric release is explored by introduction of candidate modalities for sterile manufacture per recently revised USP <1211> and <1222>.

Fidelity to Science & Correct Scientific Vocabulary-Microbial Control Versus Contamination Control.

More than at any other moment in our history, it is imperative that we maintain fidelity to sound science and ensure the correct use of the associated scientific vocabulary. This is especially the case with respect to pharmaceutical microbiology and its practice in ensuring adequate controls in the manufacture of safe and efficacious therapeutics. Here, the current state of challenges and headwinds to pharmaceutical microbiology and how these are intimately linked with fidelity to sound science and the correct use of the associated scientific vocabulary are described. This is illustrated through the specific example of a misuse of the term "microbial contamination" within regulatory guidance and the adverse consequences that all stakeholders (patients, prescribers, industry, regulators, standard setting bodies) will encounter.LAY ABSTRACT: More than at any other moment in our history, it is imperative that we maintain a fidelity to sound science and ensure the correct use of the associated scientific vocabulary. This is especially the case with respect to pharmaceutical microbiology and its practice in ensuring adequate and effective controls in the manufacture of safe and efficacious therapeutics. Here, the current state of challenges and headwinds to pharmaceutical microbiology and how these are intimately linked with fidelity to sound science and the correct use of the associated scientific vocabulary are described. This is illustrated through the specific example of a misuse of the term "microbial contamination" within regulatory guidance and the adverse consequences that all stakeholders (patients, prescribers, industry, regulators, standard setting bodies) will encounter.

The Boil Test-Strategies for Resistance Determination of Microorganisms.

The terminal sterilization of drugs and devices is the most appropriate means of assuring patient safety in terms of infection prevention. Adoption of terminal sterilization processes requires a supporting and thorough program for control and monitoring of bioburden, especially if a parametric release program of sterilization is desired. Such a control program should necessarily assess and evaluate the associated bioburden (primarily spores), which may resist inactivation and challenge the sterilization cycle. The bioburden resistance can be evaluated by several means and procedures (e.g., the boil test); however, these procedures should be designed and implemented taking into consideration the nature of the spore and spore recovery. This short review describes the application of moist heat resistance for the terminal sterilization of drugs.LAY ABSTRACT: The terminal sterilization of drugs and devices is the most appropriate means of assuring patient safety in terms of infection prevention. Adoption of terminal sterilization processes requires a supporting and thorough program for control and monitoring of bioburden, especially if a parametric release program of sterilization is desired. This short review describes the application of moist heat resistance for the terminal sterilization of drugs.

Microbiological Test Data-Assuring Data Integrity.

Marketed drugs and devices possess specifications including critical microbiological quality attributes purposed to assure efficacy and patient safety. These attributes are legislated requirements intended to protect the recipient patient. Sampling, microbiological testing, interpretation of data for final products, raw materials, and intermediates all contribute to a cohesive assessment in the assurance of finished product quality. Traditional culture-based microbiological methods possess inherent and unavoidable variability, recognized by the compendia and which might lead to erroneous conclusion pertaining to product quality. Such variability has been associated and intrinsically linked with data integrity issues; manufacturers have subsequently been encouraged by regulatory authorities to introduce multiple microbiologists or checks to prevent such issues. Understanding microbiological variability is essential such that genuine data integrity issues are identified. Furthermore, a range of meaningful preventative strategies are feasible beyond increasing the capacity of the quality control microbiological laboratory. This short review describes the legislative requirements, inherent microbiological variability, and realistic actions and activities that genuinely assure patient safety.LAY ABSTRACT: Marketed drugs and devices possess specifications including critical microbiological quality attributes purposed to assure efficacy and patient safety. These attributes are legislated requirements intended to protect the recipient patient. Sampling, microbiological testing, interpretation of data for final products, raw materials, and intermediates all contribute to a cohesive assessment in the assurance of finished product quality. Traditional culture-based microbiological methods possess inherent and unavoidable variability, recognized by the compendia and which might lead to erroneous conclusion pertaining to product quality. Such variability has been associated and intrinsically linked with data integrity issues; manufacturers have subsequently been encouraged by regulatory authorities to introduce multiple microbiologists or checks to prevent such issues. Understanding microbiological variability is essential such that genuine data integrity issues are identified. Furthermore, a range of meaningful preventative strategies are feasible beyond increasing the capacity of the quality control microbiological laboratory. This short review describes the legislative requirements, inherent microbiological variability, and realistic actions and activities that genuinely assure patient safety.

Reducing hospital-acquired infection by quantitative risk modeling of intravenous bag preparation.

Vascular access of patients by peripheral and central venous catheters for the delivery of sterile or aseptically manufactured parenterals is commonly regarded as one of the major causes of blood stream infections. Rigorous evaluation and management of the risks of microbial infection originating from the administration of aseptically manufactured therapies remain imperative to reduce patient infection risks. Healthcare clinicians are continually faced with choosing intravenous (IV) parenteral administration strategies to minimize patient blood stream infection risk. Data facilitating such decisions are often difficult to obtain. Analysis and interpretation of the available, reported hospital infection rate data to evaluate medical device- and therapy-associated infection rates are constrained by the variability and uncertainty associated with each individual administration scenario. Moreover, clinical trials quantifying infection risk are constrained by their practicality, cost, and the control of the exacting requisite trial criteria. Furthermore, it is ethically inappropriate to systematically conduct clinical evaluations incorporating conditions that do not favor the best possible patient outcomes. Quantitative risk modeling (QRM) is a unique tool offering an alternative and affective means of assessing design and clinical use in the context of the clinical environment on medical device and combinatorial therapy infection rates. Here, we report the generation of QRMs and the evaluation of manual admixing IV bags for use in IV administration sets upon patient infection rates. The manual admixing of IV bags was assessed for the opportunity and risk of microbial ingress accessing across the sterile barrier during clinical preparation and contaminating the IV solution. The risk of microbial contamination was evaluated under (a) ISO 5 compounding conditions adopting ideal aseptic technique (in compliance with USP 〈797〉) and (b) realistic worst-case point-of-care conditions (typically found in hospital wards). These choices of conditions encompass the complete spectrum of clinical environments encountered in the hospital. The evaluation estimated contamination rates ranged from <2.2 ppm (2.2 contaminated units in every million uses) to 2.9% (29 contaminated units in every 1000 uses), contingent upon the clinical environment. QRM permits the swift probabilistic evaluation of contamination rates providing the healthcare professional with data to make an informed choice of medical devices and a preparation strategy in their precise clinical context, reducing hospital acquired infections for optimal clinical patient outcomes.

Quantitative risk modeling in aseptic manufacture.

Expedient risk assessment of aseptic manufacturing processes offers unique opportunities for improved and sustained assurance of product quality. Contemporary risk assessments applied to aseptic manufacturing processes, however, are commonly handicapped by assumptions and subjectivity, leading to inexactitude. Quantitative risk modeling augmented with Monte Carlo simulations represents a novel, innovative, and more efficient means of risk assessment. This technique relies upon fewer assumptions and removes subjectivity to more swiftly generate an improved, more realistic, quantitative estimate of risk. The fundamental steps and requirements for an assessment of the risk of bioburden ingress into aseptically manufactured products are described. A case study exemplifies how quantitative risk modeling and Monte Carlo simulations achieve a more rapid and improved determination of the risk of bioburden ingress during the aseptic filling of a parenteral product. Although application of quantitative risk modeling is described here purely for the purpose of process improvement, the technique has far wider relevance in the assisted disposition of batches, cleanroom management, and the utilization of real-time data from rapid microbial monitoring technologies.

Bacterial adhesion: considerations within a risk-based approach to cleaning validation.

Pharmaceutical manufacturing processes are vulnerable to varying degrees of microbial challenge (hazard) quantifiable as microbial ingress, and microbial retention risks affecting raw materials and inputs to the final product. Control over these risks is exacted by both purposefully designed and incidental (or fortuitous) properties of the manufacturing processes. Within the manufacturing environment, equipment cleaning and hold processes are uniquely prone to microbial challenge yet paradoxically demonstrate the greatest potential for mitigation of these risks. Cognition of those components and contributing factors associated with microbial challenge are necessary to facilitate scientifically sound risk assessments. In the context of equipment cleaning and hold processes, risk assessments are necessary to identify and contrive conditions, which are truly worst case for the validation of the control of microbial challenge. A number of components contribute to the risk of microbial retention, yet the phenomenon of microbial adhesion to surfaces remains one of the most ubiquitous and perplexing. The dual purpose of this review is to primarily précis and provide in a single reference those multi-factorial features and variables contributing to bacterial adhesion, and secondly to provide a guide for interpretation of those considerations for integration into a risk-based approach to cleaning validation.

Ether-bond scission in the biodegradation of alcohol ethoxylate nonionic surfactants by Pseudomonas sp. strain SC25A.

Pseudomonas sp. strain SC25A, previously isolated for its ability to grow on alcohol ethoxylates (PEG dodecyl ethers) as sole source of carbon and energy, was shown to be capable of growth on the dodecyl ethers of mono-, di, tri- and octaethylene glycols. Comparative growth yields for this series of alcohol ethoxylate nonionic surfactants indicated that, whereas all of the carbon of monoethylene glycol dodecyl ether (MEGDE) was assimilable, only the alkyl chains were assimilated from the higher ethoxamers. These results are interpreted in terms of a primary biodegradation mechanism in which the scission of the dodecyl-ether bond is the first step. In the case of MEGDE this step separates the dodecyl chain from a C2 fragment, both of which are readily assimilable; for the higher ethoxamers, the assimilable dodecyl chain is accompanied by an ether-containing PEG derivative which would require further rounds of either scission before assimilation. Whole cells and cell extracts converted [1-14C]MEGDE initially and very rapidly to radiolabelled dodecanol. Disappearance of [14C]dodecaol was accompanied by production of [14C]dodecanal. [14C]Dodecanoic acid was present at relatively low concentrations throughout the incubation periods. [14C]Dodecan-1, 12-dioic acid was produced in significant quantities (up to 25% radiolabel), and the onset of its production coincided with the peak concentration of dodecanal, the disappearance of which mirrored the appearance of the dioic acid. Under anaerobic conditions in the presence of cell extracts, dodecanol (55% of radiolabel) and dodecanal (22%) accumulated rapidly from MEGDE, but there was little subsequent conversion to mono- or dicarboxylic acids. These results are interpreted in terms of a pathway initiated by dodecyl-ether cleavage to produce dodecanol, which is subsequently oxidized to dodecanal and dodecanoic acid. The formation of dodecan-1, 12-dioic acid, probably from dodecanal, may represent a means of harbouring carbon under non-growing conditions.

Selection in chemostat culture of a mutant strain of Clostridium tyrobutyricum improved in its reduction of ketones.

Growth of Clostridium tyrobutyricum on mannitol was possible only when an ancillary oxidant was additionally supplied. Hexacyanoferrate(III) in the presence of methylviologen could fulfil this role, which is normally better accomplished by acetate (and some other organic electron acceptors including acetoin, crotonate and 3-hydroxybutyrate). Several ketones, including pentan-2-one, although slowly reducible by the organism were unable to support its batch culture growth on mannitol. However, when a chemostat culture supplied with excess mannitol but limiting acetate was supplemented with pentan-2-one, a spontaneous mutant strain was selected that was much improved in its specific rate of reduction of this and other ketones, and which was capable of batch growth on mannitol plus pentan-2-one. This procedure may more generally be employed to select strains of anaerobic bacteria improved in their bioreductive abilities.