Volume 4 may be ordered through the PDA Bookstore by Clicking Here, and Volumes 1-3 may be ordered by Clicking Here.
One of the highlights in Volume 4 is an excellent introduction by Dr. Bryan Riley, New Drug Microbiology Staff at FDA’s Center for Drug Evaluation and Research, and the Agency’s expert on rapid method technologies. Dr. Riley explains that modern approaches to process control (including Process Analytical Technology) require the availability of results in real-time (or at least close to real-time) to enable the operator to use the test results to make process decisions and adjustments. Although real-time results are only currently available for a limited category of microbiological tests, there are many microbiological methods that are significantly more rapid than the traditional test methods.
He continues to state that the rapid methods available today vary a great deal in their mechanisms of operation. Some of these methods still rely on a period of microbial growth using traditional media but reduce their time to result by using an alternate method of microbial detection. Other rapid methods do away with growth entirely and utilize a stain or inherent microbial auto fluorescence to detect microorganisms even down to the level of a single microbial cell. Furthermore, some of the available methods are quantitative, some are qualitative, and they vary in their time to result (from real-time to several days) but all of these methods seem to have found a niche in the pharmaceutical microbiologist’s arsenal. These current rapid microbiological test methods are now able to start providing some of the advantages (from a process control and economic return standpoint) long enjoyed by our colleagues in the clinical and food microbiology labs. Pharmaceutical microbiologists would be well served by considering which of their samples would provide a benefit with a more rapid result and then assessing the current alternate microbiological methods to see if any of them are a good fit for their needs. Dr. Riley concludes that the Encyclopedia of Rapid Microbiological Methods will be an excellent resource to start that assessment.
Volume 4 includes up-to-the-minute advances and details regarding quality control, choosing appropriate methods, future use and technologies, mass spectrometry, genotypic methods for identification, new case studies, application of USP and other guidelines, environmental monitoring, validation, sterility testing, Mycoplasma testing, the application of rapid microbiological methods as they relate to both bio-processing and regulatory considerations, many product-specific method advances and much, much more. Below is a preview of each of the chapters.
Chapter 1 discusses the application of modern microbial methods to the Quality Control testing of probiotics, including master and working cell banks, release and stability testing, viable cel counts, identification and strain typing, absence of bacterial pathogens, antibiotic resistance, adherence to the intestinal wall and acid and bile resistance.
Chapter 2 provides considerations when aligning a rapid microbiological method with an end-user’s particular needs. Topics include the drivers for rapid methods, time savings, same day results, sample compatibility, automation, using a qualitative method as a screening tool, validation, identification, integration with LIMS and other data management platforms, false positives, false negatives and limit of detection.
In Chapter 3, I look to the future of rapid and automated microbial identification systems. Here, an overview of technologies based on the growth of microorganisms, the detection of cellular components, optical spectroscopy, nucleic acid amplification and MEMS is provided. Examples include the utilization of biochemical and carbohydrate substrates, fatty acid analysis, MALDI-TOF and SELDI-TOF mass spectrometry, FT-IR, elastic and inelastic light scattering, ribotyping, PCR, microfluidics and microarrays.
Chapter 4 provides a more detailed case study when using MALDI-TOF mass spectrometry for the identification of microorganisms. Sample preparation, OQ, PQ, accuracy, precision, robustness and computer validation are some of the topics discussed.
Another case study on microbial identification is provided in Chapter 5, focusing on genotypic methods, amplification of DNA, automation and validation (accuracy, precision, robustness and specificity). Compliance of the new method with GMP principles is also discussed.
In Chapter 6, a supplier of a rapid growth-based microbial identification system provides an overview of enhancements to their existing technology. The workflow and applications are reviewed, in addition to validation considerations.
A case study of a new growth-based rapid microbiological method that detects the presence of specific organisms and provides an estimation of viable cell count is provided in Chapter 7. Sample preparation, the assay workflow, and applicability to a wide-range of microorganisms are discussed. Additionally, data from a validation case study, inclusivity and exclusivity testing, and a comparison to USP <61> for aerobic counts, yeast and mold, and Gram-negative bile tolerant microorganisms, are provided.
Chapter 8 involves an end-user case study that describes an evaluation of a relatively new growth-based rapid method that utilizes a membrane filtration workflow coupled with a viability staining technique. A review of the technology and evaluation results are offered followed by a discussion of the system’s use for monitoring mammalian cell cultures and additional benefits.
In Chapter 9, an optical spectroscopy rapid method supplier describes an environmental monitoring system and how to apply to validation recommendations of USP <1223> to their technology. Accuracy, precision, limit of detection and quantification, linearity, range, ruggedness and robustness are some of the parameters that were examined.
In Chapters 10 and 11, I review a comprehensive evaluation using an optical spectroscopy technology for the real-time and continuous monitoring of airborne microorganisms in cleanroom and isolator environments. Complete with plenty of pictures, the reader will be immersed in a study of real-time monitoring during an aseptic fill, the transfer of sterilized components, interventions and when the integrity of isolator gloves has been breached.
A rapid method for the release testing of both sterile (sterility testing) and non-sterile products (bioburden assessments) is the focus of Chapter 12. Here, an ATP bioluminescence technology is validated, and the authors discuss their qualification workflow and results.
Chapter 13 describes an end-user’s validation approach for a rapid, growth-based detection system as an alternate sterility test for cellular immunotherapy products. Challenges with the conventional method are discussed, followed by their approach to feasibility testing, method validation, and a regulatory path for commercial approval.
Chapter 14 is another case study by an end-user of a rapid, solid-phase cytometry technology. The author describes their validation strategy, including accuracy, precision, limit of detection, robustness, ruggedness and the use of statistical models when comparing the results to the acceptance criteria. Additional considerations are discussed, including the use of stressed cells and matrix effects on the overall validation plan.
Another supplier describes their ATP bioluminescent system as an alternative to the conventional sterility test, in Chapter 15. Validation strategies, the use of challenge microorganisms, system suitability, understanding background values, and how to conduct product specific feasibility testing, are just some of the topics that are discussed.
Chapter 16 focuses on the statistics of validating an alternative sterility test. Subjects include probabilities and multiplicity, limit of detection and a comparison of what is statistically different versus what is statistically equivalent. This is a must read for anyone wanting to validate a rapid sterility test and how to design the studies and use statistics to justify the results.
Chapter 17 provides an over of a validation approach for a next-generation ATP monitoring technology. The principle of the new method, how to evaluate limit of detection and validation strategies for a wide-range of fluid samples are provided.
A novel qPCR-based system for the detection of specific microorganisms is the focus in Chapter 18. An overview of the technology by the system’s supplier is provided, in addition to a preliminary study on validation parameters, specificity, limit of detection and data analysis.
Chapter 19 addresses the use of rapid methods for the detection of Mycoplasma. These end-users provide an overview of Mycoplasma and the importance of detection in the biopharmaceutical industry, traditional and alternative methods, and a case study using a nucleic acid amplification platform. A review of regulatory author requirements for nucleic acid amplification systems is also discussed.
A new nucleic acid amplification and microarray-based rapid method for the detection of Mycoplasma is highlighted in Chapter 20. The technology workflow and advantages over traditional methods is discussed, and regulatory guidelines for Mycoplasma detection are examined.
Chapter 21 provides an overview of rapid viral detection methods. Classic versus molecular biology approaches are discussed, in addition to the prospects for viral safety testing. Experiences with Vesivirus, MVM and other public viral incidents are explored, as well as other topics associated with the future directions in using molecular methods for detection.
Speaking of future directions, Chapter 22 investigates the new microbiology technology wave: alternative and rapid methods for the QC laboratory. Regulations, skill sets for the pharmaceutical microbiologists, and the microbiological curricula are but a few topics provided.
Finally, Chapter 23 goes into great depth in discussing the application of rapid microbiological methods for bioprocessing. A review of biopharmaceutical manufacturing, regulations, testing requirements and contamination events sets the stage for considering a wide range of rapid method applications.