
PDA Technical Glossary
PDA Technical Reports are highly valued membership benefits because they offer expert guidance and opinions on important scientific and regulatory topics and are used as essential references by industry and regulatory authorities around the world. These reports include terms which explain the material and enhance the reader’s understanding.
The database presented here includes the glossary terms from all current technical reports. The database is searchable by keyword, topic, or by technical report. Each definition provided includes a link to the source technical report within the PDA Technical Report Portal.
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- TR 70: Cleaning/Disinfection Programs (14)
- TR 69: Bioburden/Biofilm Management (13)
- TR 22: Aseptic Process Simulation (13)
- TR 47: Virus Spikes/Virus Clearance (11)
- TR 50: Alt. Methods Mycoplasma Testing (10)
- TR 62: Manual Aseptic Processes (10)
- TR 51: Biological Indicators (8)
- TR 45: Depth Filtration (8)
- TR 71: Emerging Methods for Virus Detection (6)
- TR 13: Environmental Monitoring (6)
- TR 67: Objectionable Microorganisms (5)
- TR 3: Validation: Dry Heat (5)
- TR 15: Validation: TFF in Biopharmaceuticals (5)
- TR 28: Process Simulation for Bulk API (5)
- TR 41: Virus Filtration (5)
- TR 26: Sterilizing Filtration of Liquids (4)
- TR 83: Virus Contamination in Biomanufacturing: Risk Mitigation, Preparedness, and Response (4)
- TR 88: Microbial Data Deviation Investigations in the Pharmaceutical Industry (4)
- TR 77: The Manufacture of Sterile Pharmaceutical Products Using Blow-Fill-Seal Technology (4)
- TR 33: Rapid Micro Methods (4)
- TR 57: Analytical Method Validation (3)
- TR 61: Steam in Place (3)
- TR 14: Validation: Protein Purification Chromatography (3)
- TR 29: Validation: Cleaning (3)
- TR 48: Moist Heat Sterilizer Systems (2)
- TR 49: Validation: Cleaning Biotech (2)
- TR 55: TBA/TCA Detection Mitigation (2)
- TR 60: Process Validation (2)
- TR 66: Single-Use Systems (2)
- TR 74: Reprocessing of Biopharmaceuticals (2)
- TR 1: Validation: Moist Heat (2)
- TR 78: Particulate Matter in Oral Dosage Forms (2)
- TR 42: Validation: Protein Manufacturing (2)
- TR 44: QRM: Aseptic Processes (2)
- TR 53: Stability Testing New Drug Products (1)
- TR 56: Phase Appropriate cGMP Application (1)
- TR 57-2: Analytical Method Development (1)
- TR 58: Temp Controlled Distribution (1)
- TR 84: Integrating Data Integrity Requirements into Manufacturing & Packaging Operations (1)
- TR 75: Mycoplasma Filter Rating Method (1)
- TR 38: Manufacturing Chromatography Systems Postapproval Changes (ChromPAC) (1)
- TR 85: Enhanced Test Methods - Visible Particle Detection/Enumeration Closures/Containers (1)
- TR 82: Low Endotoxin Recovery (1)
- TR 30: Parametric Release (1)
- TR 43: Glass Defects (1)
Filter By Technical Report Keyword
- Microbiology (103)
- Manufacturing (93)
- GMP/Good Manufacturing Processes/cGMP (81)
- Quality Risk Management/QRM (53)
- Validation (51)
- Virus (30)
- Filtration (21)
- Packaging Science (16)
- Combination Products (13)
- Vaccines (6)
- Inspections (4)
- Prefilled Syringes/PFS (4)
- Technology Transfer (4)
- Supply Chain (2)
- Visual Inspection (1)
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Action Level
An established microbial or airborne particle level that, when exceeded, indicates a process is outside of its normal operating range. A response to such an excursion should involve a documented investigation and corrective actions based on the results of that investigation. (TR13)
An established microbial or non-viable particle level that, when exceeded, should trigger appropriate investigation and corrective action based on the investigation. (TR22)
An established microbial or airborne particle level for environmental, water or gas monitoring that, when exceeded, indicates that a facility process is outside of its normal operating range. The response to such an excursion involves a documented investigation and corrective actions based on the results of that investigation. The prescribed action level is often specified in guidance or standards relating to environmental monitoring and water quality. (TR69)
An established microbial or nonviable particle level for environmental, water, or gas monitoring that, when exceeded, indicates a facility or process is outside of its normal operating range. The response to such an excursion may involve a documented investigation and corrective actions based on the results. The prescribed action level is often specified in guidances or standards relating to environmental monitoring and water quality (3-6). (TR88)
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Action Level (environmental monitoring)
An established microbial or non-viable particle level that, when exceeded, should trigger appropriate investigation and corrective action based on the investigation. (TR22)
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Action Limit
An internal (in-house) value used to assess the consistency of the process. The cause of the excursion should be investigated and documented and corrective action is generally required. Action limits are not specifications. (TR42)
An established internal (in-house) data-based value which is part of the control strategy and used to assess the consistency of the manufacturing process. An action limit excursion result in an investigation, identification of recovered isolates, root-cause analysis, assessment of a systemic failure and impact on product quality and patient safety. (TR69)
An established internal (in-house) data-based value that is part of the control strategy and used to assess the consistency of the manufacturing process. An action limit excursion result in an investigation, identification of recovered isolates, root-cause analysis, assessment of a systemic failure and impact on product quality and patient safety. (TR74)
A limit that, when exceeded, indicates a process is outside of its normal operating range. A response to such an excursion should involve a documented investigation and corrective actions based on the results of that investigation. (TR60)
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Advanced Aseptic Process
A process in which direct intervention with open product containers or exposed product contact surfaces by operators wearing conventional cleanroom garments is not required and never permitted. (TR77)
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Adventitious Agents
A foreign material that is introduced inadvertently; not natural or hereditary (as in microbial, chemical, or biochemical contamination of a purified substance). (TR 69)
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Adverse Event (AE) Report
An AE report is a communication to the U.S. FDA of an undesirable sign or symptom associated with use of a drug as required and detailed by 21 CFR 314.80. These reports are logged into the U.S. FDA’s Adverse Event Reporting System (AERS). Drug manufacturers are required to report adverse event information to FDA. These reports may also may be voluntarily submitted to the FDA directly by healthcare professionals or the general public at Med Watch. The reports are reviewed, safety issues are monitored, and data are periodically analyzed and assessed by the Center for Drug Evaluation and Research (CDER). (TR55)
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Adverse Trend
A series of alert-level or action-level excursions that indicates the system or areas are not in control and have the potential to affect the product quality. (TR 70)
An increase in the frequency of alert- and action-level excursions or repeated recovery of low levels of microorganisms below the alert level during microbial monitoring or of pharmaceutical ingredient or finished product failure that is indicative of a loss of process control. (TR88)
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Aerobic Microorganism
A microorganism that utilizes oxygen as the final electron acceptor during metabolism; a microorganism that will grow primarily in the presence of oxygen. For the purpose of this report, this definition encompasses facultative anaerobes. (TR22) (TR62)
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Aggregation
Clumping of proteins, viruses, or bacteria that may arise from several mechanisms and may be classified in numerous ways, including soluble/insoluble, covalent/noncovalent, reversible/irreversible, and native/denatured. (TR47)
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Air Removal Test
A test used to evaluate air removal and steam penetration in an empty sterilizer that is used for porous/hard goods load sterilization (e.g., Bowie-Dick Test, DART, Lantor Cube, Browns’ Test). (TR01) (TR 48)
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Airlock
A room that controls the airflow between two rooms of different classification. (TR 70)
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Alert Level
An established microbial or nonviable particle level giving early warning of potential drift from normal operating conditions; not necessarily grounds for definitive corrective action but typically requires follow-up investigation. (TR13) (TR22) (TR69)
An established level that, when exceeded, is giving an early warning of a potential drift from normal operating conditions; while not necessarily grounds for definitive corrective action, it typically requires follow-up review. (TR 60)
An established microbial or nonviable particle level giving early warning of potential drift from normal operating conditions; not necessarily grounds for definitive corrective action, but typically requires follow-up investigation (3, 4, 7). (TR88)
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Alert Limit
An established internal (in-house) data-based value giving early warning of potential drift of manufacturing process from normal operating conditions and triggers appropriate follow-up investigations. Alert limits are always lower than action limits. (TR69)
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Alternative or Rapid Microbiological Method (RMM)
A novel, modern and/or fast microbiological testing method that is different from a classical or traditional growth-based method, such as agar-plate counting or recovery in liquid broth media. The alternative or rapid method may utilize instrumentation and software to manage the testing and resulting data, and may provide quantitative, qualitative and/or microbial identification test results. Automated technologies that utilize classical growth-based methods may also be designated as being novel, modern or rapid, based on their scientific principle and approach to microbial detection. The terms alternative, rapid microbiological method, rapid method and the acronym RMM are used interchangeably within this technical report. (TR33)
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Amplicon
A segment of double stranded DNA formed as the product of polymerase chain reaction or other amplification based techniques such as TMA or NASBA. (TR50)
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Anaerobe
An organism that has the ability to grow in the absence of oxygen. (TR51)
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Antimicrobial Chemical Agent
Substance used to destroy or suppress the growth of microorganisms, whether bacteria, fungi, or viruses, on inanimate objects and surfaces. (TR70)
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Area Disinfection
Disinfection of floors, walls, ceilings, and other surfaces. (TR70)
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Aseptic Processing
Handling sterile materials in a controlled environment, in which the air supply, facility, materials, equipment and personnel are regulated to control microbial and particulate contamination to acceptable levels. (TR28) (TR62) (TR69) Handling of sterile product, containers, and/ or devices in a controlled environment in which the air supply, materials, equipment, and personnel are regulated to maintain (product) sterility. (TR13)
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Aseptic Processing Area (APA)
Controlled environment, consisting of several zones, in which the air supply, facility, materials, equipment and personnel are regulated to control microbial and particulate contamination to acceptable levels. (TR22) (TR28) (TR62) (TR70)
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Aseptic Processing Simulation (APS)
A means for establishing the capability of an aseptic process as performed using a growth medium. (TR22) (TR62)
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Autoclave
A chamber for steam sterilization. (TR45)
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Bacterial Endotoxin Test (BET)
Assay for measuring active endotoxin by combining a liquid test sample with Limulus amebocyte lysate (LAL) reagent and measuring the resulting proportional reaction via visual, turbidimetric, chromogenic, or other validated means of detection. (TR3)
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Ballotini
Small glass beads (spheres) obtainable in a range of sizes, used in the recovery of spores from paper carriers. (TR51)
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Bioburden
The total number of microorganisms per unit of material prior to sterilization. (TR13) Total number of viable microorganisms on or in a health care product prior to sterilization. (TR22)(TR61)(TR62) A population of viable microorganisms in a fluid prior to sterilizing filtration. (TR26) A measure of the contaminating organisms found in or on a given amount of material before it undergoes a sterilization process. (TR45) (TR70) The number of detectable microorganisms (bacteria and fungi) with which an object is contaminated. It is measured in CFU (colony forming units). (TR47) The number of viable, contaminating microorganisms present on a product immediately prior to decontamination. (TR51) Viable microbial contaminants associated with personnel manufacturing environments (air and surfaces), equipment, product packaging, raw materials (including water), in-process materials, and finished products. (TR 67) (TR 69)
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Biological Activity
Property that describes the specific ability or capacity of a product to achieve a defined biological effect. (TR57)
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Biological Indicator (BI)
An inoculated carrier contained within its primary pack ready for use and providing a defined resistance to the specified sterilization process. (TR51)
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Biological Medicinal Product
A product (therapeutic or prophylactic) for human use that has been manufactured in or from a biological source. Examples include recombinant therapeutic proteins or vaccines. Biological medicinal products are also referred to as: biological medicines, biological products, biologics and biologic drugs. (TR 71)
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Biological Qualification
A component of performance qualification that demonstrates, by use of biological indicators, that the required lethality (FBIO) is achieved consistently throughout the load. (TR1) (TR3) (TR30) A component of performance qualification that demonstrates, by use of biological indicators, that the required lethality (FBIO) or spore log reduction (SLR) is achieved consistently throughout the sterilized or sanitized portion of the SIP system. (TR61)
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Biological Safety Cabinet (BSC)
An enclosed, ventilated workspace with engineering controls designed to remove or minimize exposure to hazardous biological materials. A BSC is a principle device to provide containment of infectious splashes or aerosols generated by many microbiological procedures. BSCs are designed to provide personnel, environmental and product protection when appropriate practices and procedures are followed. A cabinet that is designed to protect the operator and the environment from the hazards of handling infected material and other dangerous biological. (TR62)
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Biological Tests
Biological tests include animal, cell culture, or biochemical based testing that measures a biological, biochemical, or physiological response. (TR38)
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Biologics License Application (BLA)
An application, filed with the US Food and Drug Administration (FDA), which contains specific information on the manufacturing processes, chemistry, pharmacology, clinical pharmacology and the medical effects of the biologic product (similar function as the Marketing Authorization Application in Europe). (TR56)
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Biomethylation
The enzyme chlorophenol o-methyltransferase responsible for fungal methylation has been isolated in cell-free extracts. Biomethylation, in this context, may be seen as a detoxification mechanism, although it plays a role in the production of mycotoxins by secondary metabolism. Slightly xerophilic fungi frequently associated halophenol biomethylation include Trichoderma longibrachiatum, Trichoderma virgatum, Aspergillus sydowii, and Penicillium islandicum. (TR55)
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CE Marking
The CE marking is a key indicator of a product’s compliance with EU legislation and enables the free movement of products within the European market. (TR58)
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Characterization Method
Scientifically sound method of a generally complex nature that is used for nonroutine assessment of specific biochemical, chemical, physicochemical, immunochemical, microbiological, and biological characteristics or inherent properties of a compound. (TR 57-2)
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Characterization Study
A series of tests designed to increase process knowledge by examining proposed operational ranges and their individual and/or combined impact on the chromatography process. (TR14) A late-stage study that evaluates the process to increase process knowledge and examines proposed operational ranges and their individual and/or combined impact on target protein quality. (TR42)
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Contaminant
Any adventitiously or externally introduced material(s) (e.g., chemical, biochemical, or microbial species) not intended to be part of the process. (TR14) (TR15) (TR70)
An undesired impurity of a chemical or microbiological nature that is introduced into a raw material, intermediate, or API (drug substance) during manufacture. (TR14) (TR15)
Any adventitiously introduced materials (e.g., chemical, biochemical, or microbial species) not intended to be part of the manufacturing process of the drug substance or drug product. (TR69) (TR74)
Any adventitiously introduced material (e.g., chemical, biochemical) or microorganisms including viruses not intended to be included in the manufacturing process of the drug substance or drug product. (TR83)
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Contamination Rate
The percentage of units filled in a process simulation that are positive for microbial growth after incubation. (TR22)
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Coupon
A small, generally flat portion of a defined material of construction (such as stainless steel or PTFE) and of a defined surface finish, typically used for laboratory cleaning evaluations and/or for laboratory sampling recovery studies. (TR29) (TR49)
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Critical Area/Critical Zone
An area designed to maintain sterility of sterile materials. Sterilized product, containers, closures, and equipment may be exposed in critical areas. (TR13) (TR22) (TR44) (TR62)
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Critical Process (CP)
A process that impacts a critical quality attribute of the intermediate, drug substance or drug product being manufactured and therefore should have established critical process parameters that can be monitored or controlled to ensure that the process produces the desired quality.
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Cross-Flow Rate
Volumetric rate of fluid flow parallel to the membrane surface. (TR15)
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Cytopathic Effect (CPe)
Morphological changes induced by viruses in infected cells in invitro culture. They are usually localized around a site of initial infection and vary in appearance based on the virus and the cultured cell. (TR47)
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Cytopathic Virus
Viruses where infection of cells results in microscopically visible degeneration of the cells or other morphological changes. (TR47)
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Decontamination
A process that is designed to remove soil (including microorganisms) and may consist of cleaning and/or disinfection. (TR51)
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Degradation
The breakdown (usually chemical) of material during manufacture, including during and after the cleaning process. (TR49) (TR70)
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Degradation Product
Molecular variants resulting from changes in the desired product or product-related substance brought about over time and/or by the action of light, temperature, pH, water, etc., or by reaction with an excipient and/or the immediate container/ closure system. Such changes may occur because of manufacture and/or storage (e.g., deamidation, oxidation, aggregation, proteolysis). Degradation products may be either product-related substance or product-related impurities. (TR57)
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Deionized Water
Water treated by passing through both cation- and anion-exchange resin beds, or a mixed-resin bed to remove both positive and negative ions. (TR45)
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Depyrogenation
The destruction and/or removal of bacterial endotoxins. A depyrogenation process should demonstrate at least 99.9% or a 3-log endotoxin reduction. (TR3) Removal or destruction of pyrogens. (TR70)
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Detergent
A synthetic wetting agent and emulsifier that can be added to a solvent to improve its cleaning efficiency. (TR70)