
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 1: Validation: Moist Heat (39)
- TR 70: Cleaning/Disinfection Programs (31)
- TR 48: Moist Heat Sterilizer Systems (26)
- TR 3: Validation: Dry Heat (26)
- TR 13: Environmental Monitoring (24)
- TR 61: Steam in Place (22)
- TR 69: Bioburden/Biofilm Management (21)
- TR 51: Biological Indicators (19)
- TR 22: Aseptic Process Simulation (19)
- TR 45: Depth Filtration (18)
- TR 62: Manual Aseptic Processes (17)
- TR 47: Virus Spikes/Virus Clearance (14)
- TR 50: Alt. Methods Mycoplasma Testing (14)
- TR 41: Virus Filtration (14)
- TR 26: Sterilizing Filtration of Liquids (13)
- TR 29: Validation: Cleaning (12)
- TR 15: Validation: TFF in Biopharmaceuticals (11)
- TR 57: Analytical Method Validation (10)
- TR 30: Parametric Release (9)
- TR 28: Process Simulation for Bulk API (8)
- TR 33: Rapid Micro Methods (8)
- TR 66: Single-Use Systems (7)
- TR 67: Objectionable Microorganisms (7)
- TR 71: Emerging Methods for Virus Detection (6)
- TR 76: Identification and Classification of Visible Nonconformities in Elastomeric Components and Aluminum Seals for Parenteral Packaging (6)
- TR 88: Microbial Data Deviation Investigations in the Pharmaceutical Industry (5)
- TR 77: The Manufacture of Sterile Pharmaceutical Products Using Blow-Fill-Seal Technology (5)
- TR 44: QRM: Aseptic Processes (5)
- TR 49: Validation: Cleaning Biotech (4)
- TR 57-2: Analytical Method Development (4)
- TR 14: Validation: Protein Purification Chromatography (4)
- TR 83: Virus Contamination in Biomanufacturing: Risk Mitigation, Preparedness, and Response (4)
- TR 42: Validation: Protein Manufacturing (4)
- TR 55: TBA/TCA Detection Mitigation (3)
- TR 60: Process Validation (3)
- TR 75: Mycoplasma Filter Rating Method (3)
- TR 85: Enhanced Test Methods - Visible Particle Detection/Enumeration Closures/Containers (3)
- TR 74: Reprocessing of Biopharmaceuticals (2)
- TR 38: Manufacturing Chromatography Systems Postapproval Changes (ChromPAC) (2)
- TR 78: Particulate Matter in Oral Dosage Forms (2)
- TR 54-5: Quality Risk Management for the Design, Qualification, and Operation of Manufacturing Systems (2)
- TR 43: Glass Defects (2)
- TR 52: Supply Chain GDP (1)
- TR 53: Stability Testing New Drug Products (1)
- TR 54: QRM:Manufacturing Operations (1)
- TR 54-4: QRM: Biotech Drug Substance (1)
- TR 56: Phase Appropriate cGMP Application (1)
- TR 58: Temp Controlled Distribution (1)
- TR 64: Temp Controlled Systems Qualification (1)
- TR 68: Drug Shortage Management (1)
- TR 84: Integrating Data Integrity Requirements into Manufacturing & Packaging Operations (1)
- TR 82: Low Endotoxin Recovery (1)
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- Manufacturing (269)
- GMP/Good Manufacturing Processes/cGMP (212)
- Microbiology (201)
- Validation (163)
- Quality Risk Management/QRM (125)
- Biotechnology (118)
- Filtration (45)
- Virus (39)
- Packaging Science (23)
- Combination Products (15)
- Technology Transfer (13)
- Vaccines (8)
- Prefilled Syringes/PFS (6)
- Inspections (5)
- Supply Chain (4)
- Visual Inspection (2)
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AOAC International (Association Official Analytical Communities)
Serves communities of the analytical sciences by providing the tools and processes necessary to develop voluntary consensus standards or technical standards through stakeholder consensus and working groups in which the fit-for-purpose and method performance criteria are established and fully documented. (TR55)
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Accelerated Stability Testing
Studies designed to increase the rate of chemical degradation or physical change of a drug substance or drug product by using exaggerated storage conditions as part of the formal stability studies. (TR57-2)
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Acceptance Limit
The maximum amount of residue allowed in a product, in an analytical sample, or as an amount per surface area. (TR29)
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Accuracy
The closeness of the actual test results obtained by the new method to the actual test results obtained by the existing method. (TR33) An analytical procedure expresses the closeness of agreement between the value that is accepted either as a conventional true value or an accepted reference value and the value found. This is sometimes termed trueness. (TR57)
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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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Airborne Particulate Count (Total Particulate Count)
The total number of particles of a specific size per unit volume of air. (TR13)
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Airborne Viable Particulate Count (Total Airborne Aerobic Microbial Count)
The total number of particles of a specific size per unit volume of air. (TR13)
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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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Attachment (Adhesion)
Discrete association of a microorganism with an animate or inanimate surface. (TR69)
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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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Bias
A systematic difference in a method that manifests itself as a deviation of the method mean from an expected value. (TR57) Total systematic error, in contrast to random error. Measurement centered on the true result is said to be unbiased or have no systematic error. The distance between the center of a large (infinite) number of measurements and the correct value is the bias. (TR 57-2)
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Bioanalytical Test Method
A method used to assess the presence of analytes (chemical or biological) in biological samples (e.g., serum, plasma, etc.). (TR57)
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Bioassay
Analysis (as of a drug) to quantify the biological activity(ies) of one or more components by determining its capacity for producing an expected biological activity. (TR57)
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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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Biofouling (or Biological Fouling)
Accumulation and subsequent deleterious effects of biological contaminants on engineered products or processes (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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Bubble Point Test
A test to indicate the maximum pore size of a filter. The differential gas pressure at which a liquid (usually water) is pushed out of the largest pores and a steady stream of gas bubbles is detected from a previously wetted filter under specific test conditions. Used to test filter integrity with specific, validated, pressure values, wetting liquids and temperatures for specific pore-size (and type of ) filters. (TR26)
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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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Change Management
A systematic approach to proposing, evaluating, approving, implementing, and reviewing changes. (TR 51) (TR 54-5)
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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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Cleanroom
A room designed, maintained, and controlled to prevent particle and microbiological contamination of a drug product or medical device. A cleanroom is assigned and reproducibly meets an appropriate air cleanliness classification. (TR13)