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 84: Integrating Data Integrity Requirements into Manufacturing & Packaging Operations (8)
- TR 80: Data Integrity Management System for Pharmaceutical Laboratories (7)
- TR 45: Depth Filtration (6)
- TR 60: Process Validation (5)
- TR 70: Cleaning/Disinfection Programs (5)
- TR 51: Biological Indicators (4)
- TR 57: Analytical Method Validation (4)
- TR 26: Sterilizing Filtration of Liquids (4)
- TR 48: Moist Heat Sterilizer Systems (3)
- TR 1: Validation: Moist Heat (3)
- TR 3: Validation: Dry Heat (3)
- TR 14: Validation: Protein Purification Chromatography (3)
- TR 88: Microbial Data Deviation Investigations in the Pharmaceutical Industry (3)
- TR 76: Identification and Classification of Visible Nonconformities in Elastomeric Components and Aluminum Seals for Parenteral Packaging (3)
- TR 54-5: Quality Risk Management for the Design, Qualification, and Operation of Manufacturing Systems (3)
- TR 54-2: QRM: Packaging Labeling (2)
- TR 56: Phase Appropriate cGMP Application (2)
- TR 57-2: Analytical Method Development (2)
- TR 58: Temp Controlled Distribution (2)
- TR 61: Steam in Place (2)
- TR 67: Objectionable Microorganisms (2)
- TR 68: Drug Shortage Management (2)
- TR 69: Bioburden/Biofilm Management (2)
- TR 74: Reprocessing of Biopharmaceuticals (2)
- TR 13: Environmental Monitoring (2)
- TR 15: Validation: TFF in Biopharmaceuticals (2)
- TR 86: Industry Challenges and Current Technologies for Pharmaceutical Package Integrity Testing (2)
- TR 29: Validation: Cleaning (2)
- TR 41: Virus Filtration (2)
- TR 42: Validation: Protein Manufacturing (2)
- TR 43: Glass Defects (2)
- TR 47: Virus Spikes/Virus Clearance (1)
- TR 49: Validation: Cleaning Biotech (1)
- TR 53: Stability Testing New Drug Products (1)
- TR 54: QRM:Manufacturing Operations (1)
- TR 54-3: QRM: Drug Products (1)
- TR 54-4: QRM: Biotech Drug Substance (1)
- TR 71: Emerging Methods for Virus Detection (1)
- TR 38: Manufacturing Chromatography Systems Postapproval Changes (ChromPAC) (1)
- TR 79: Particulate Matter Control in Difficult to Inspect Parenterals (1)
- TR 30: Parametric Release (1)
- TR 77: The Manufacture of Sterile Pharmaceutical Products Using Blow-Fill-Seal Technology (1)
- TR 44: QRM: Aseptic Processes (1)
Filter By Technical Report Keyword
- Manufacturing (57)
- Quality Risk Management/QRM (38)
- Validation (33)
- Biotechnology (27)
- GMP/Good Manufacturing Processes/cGMP (27)
- Microbiology (20)
- Sterile Processing (20)
- Technology Transfer (18)
- Filtration (11)
- Packaging Science (11)
- Supply Chain (4)
- Visual Inspection (4)
- Outsourcing (3)
- Virus (2)
- Inspections (1)
- Prefilled Syringes/PFS (1)
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D-Value
The time in minutes required for a one-logarithm, or 90%, reduction of the population of microorganisms used as a biological indicator under specified lethal conditions. For dry-heat sterilization, the D-value should always be specified with a reference temperature, DT. For example, a biological indicator (BI) challenge system with a D 160°C=1.9 minutes, requires 1.9 minutes at 160°C to reduce the population by one logarithm. (TR3) The time in minutes at a specific temperature required to reduce the population of a specific microorganism by 90% [or one (1) log] in defined conditions [e.g., method of sterilization (dry heat versus steam), solute, or carrier]. (TR13)
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D-value (D10 -Value)
The time in minutes required for a one-logarithm, or 90%, reduction of the population of microorganisms used as a biological indicator under specified lethal conditions. (TR51)
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DT Value
The time in minutes required for a onelogarithm, or 90%, reduction of the population of microorganisms used as a biological indicator under specified lethal conditions. For steam sterilization, the D-value should always be specified with a reference temperature, DT . For example, a BI system with a D121°C = 1.4 minutes requires 1.4 minutes at 121°C to reduce the population by one logarithm.(TR1) (TR61)
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Darcy Permeability
The constant of proportionality of the material as defined by Darcy’s Law. (TR45)
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Darcy’s Law
Darcy’s Law states that the volumetric flow rate Q of liquid through a specimen of porous material is proportional to the hydrostatic pressure difference ∆p across the specimen, inversely proportional to the length L of the specimen and proportional to the cross-sectional area A. Darcy’s Law is expressed as Q = kA ∆p/L. (TR45)
Data (MHRA)
Facts, figures and statistics collected together for reference or analysis. All original records and true copies of original records, including source data and metadata and all subsequent transformations and reports of these data, that are generated or recorded at the time of the GXP activity and allow full and complete reconstruction and evaluation of the GXP activity.(TR80)
Data (WHO)
Data means all original records and true copies of original records, including source data and metadata and all subsequent transformations and reports of this data, which are generated or recorded at the time of the GXP activity and allow full and complete reconstruction and evaluation of the GXP activity. Data should be accurately recorded by permanent means at the time of the activity. Data may be contained in paper records (such as worksheets and logbooks), electronic records and audit trails, photographs, microfilm or microfiche, audio- or video-files or any other media whereby information related to GXP activities is recorded.(TR80)
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Data Integrity (FDA)
Refers to the completeness, consistency, and accuracy of data. Complete, consistent, and accurate data should be attributable, legible, contemporaneously recorded, original or a true copy, and accurate (ALCOA).(TR80) (TR84)
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Data Integrity (MHRA)
The degree to which data are complete, consistent, accurate, trustworthy, reliable and that these characteristics of the data are maintained throughout the data life cycle. The data should be collected and maintained in a secure manner, so that they are attributable, legible, contemporaneously recorded, original (or a true copy) and accurate. Assuring data integrity requires appropriate quality and risk management systems, including adherence to sound scientific principles and good documentation practices.(TR80) (TR84)
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Data Integrity (WHO)
The degree to which data are complete, consistent, accurate, trustworthy and reliable and that these characteristics of the data are maintained throughout the data life cycle. The data should be collected and maintained in a secure manner, such that they are attributable, legible, contemporaneously recorded, original or a true copy and accurate. Assuring data integrity requires appropriate quality and risk management systems, including adherence to sound scientific principles and good documentation practices.(TR80) (TR84)
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Data Integrity Controls
Controls put in place to either minimize the potential for a data integrity issue to occur or, if an issue does occur, the controls applied to increase the probability of detection.(TR84)
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Data Lake
A storage repository that holds, in a structured way, a vast amount of raw data, including metadata, in its native format until it is needed. (TR84)
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Data Lifecycle (MHRA)
All phases in the life of the data (including raw data) from initial generation and recording through processing (including transformation or migration), use, data retention, archive/retrieval and destruction.(TR80) (TR84)
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Data Lifecycle (WHO)
All phases of the process by which data is created, processed, reviewed, analyzed and reported, transferred, stored and retrieved and monitored until retirement or disposal. There should be a planned approach to assessing, monitoring and managing the data and the risks to those data in a manner commensurate with potential impact on patient safety, product quality and/or the reliability of the decisions made throughout all phases of the data life cycle. (TR80)(TR84)
Data Process Flow Map
A flow map that uses a baseline process flow map and overlays the data flow. (TR84)
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Data Vulnerability
An indicator of data’s level of exposure to data integrity failures due to intrinsic weaknesses in manufacturing processes, data-capture technology, and human factors or a combination thereof.(TR84)
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Date of Manufacture
For small molecules, the date of manufacture of a drug product is considered to be the initial date that an active ingredient has been added during manufacturing. For biologics the date of manufacture can be determined in multiple ways and should be consistent with internal quality systems and the product license application. (TR53)
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De Novo Sequence Assembly
Assembly of short reads of a sequence to generate a contiguous sequence (contig). (TR71)
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Dead Leg
Area of entrapment in a vessel or piping run that could lead to contamination of the product. (TR69)
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Deadlegs
An area of entrapment in the vessel or piping run that could lead to contamination of the product due to insufficient exposure to moist heat. (TR61)
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Decision Maker(s)
Person(s) with the competence and authority to make appropriate and timely quality risk management decisions.(TR54) (TR54-2)
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Decommissioning
A planned and orderly removal of a facility, operation or system from use. (TR48)
The process of retiring equipment/systems/facilities from production use. (TR54-5)
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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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Dedicated Equipment
Equipment used exclusively for the manufacture of only one drug product, bulk drug substance, or intermediate. (TR29)
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Defect
(1) A departure of a quality characteristic from its intended level or state that occurs with a severity sufficient to cause an associated product or service not to satisfy its intended normal or foreseeable usage requirements. (TR51) (2) The nonfulfillment of intended usage requirements. The departure or absence of one or more quality characteristics from intended usage requirements. (TR43)
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Defect (ANSI def.)
A departure of a quality characteristic from its intended level or state that occurs with a severity sufficient to cause an associated product or service not to satisfy its intended normal or foreseeable usage requirements. (TR76)
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Defect (ISO def.)
The nonfulfillment of intended usage requirements. The departure or absence of one or more quality characteristics from intended usage requirements. (TR76)
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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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Deployment
Activities involving the hands-on steps required to successfully assemble and make a system ready for use for a specific SUS application. (TR66)
Depth Filter
A matrix of randomly distributed fibers creating a tortuous path with pores of undefined size and shape. A filter that removes particles by a combination of adsorption and size exclusion within its porous matrix rather than on its frontal surface. (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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Design Qualification (DQ)
Documented verification that the proposed design of the systems is suitable for the intended purpose. Also establishing confidence that ancillary component systems are capable of consistently operating within established limits and tolerances. (TR39) (TR48) (TR64) (TR 72)
Design Reviews
Planned and systematic reviews of specifications, design, and design development and continuous improvement changes performed as appropriate throughout the lifecycle of the manufacturing system. Design reviews evaluate deliverables against standards and requirements, identify problems, and propose required corrective actions. (TR54-5)
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Design Space
The multidimensional combination and interaction of input variables (e.g., material attributes) and operational parameters that have been demonstrated demonstrated to provide assurance of quality. Working within the design space is not considered as a change. Movement out of the design space is considered to be a change and would normally initiate a regulatory post approval change process. Design space is proposed by the applicant and is subject to regulatory assessment and approval. (TR30) (TR60) (TR 57-2)
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Design Specification
Controlled documentation that clearly and explicitly defines the manufacturing system details, codes, and standards to be followed during fabrication and construction to meet associated requirements. (TR54-5)
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Design of Experiments (DOE)
A method for carrying out carefully planned experiments on a process. Usually, DoE involves a series of experiments that initially involves evaluating many variables and then focuses on a few critical ones. (TR54-4)
A structured, organized method for determining the relationship between factors affecting an assay and output of that assay. (TR57) (TR57-2) (TR74)
A structured, organized method for determining the relationship between factors affecting a process and the output of that process (8). (TR60)
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Design, Experimental
The arrangement of factors and factor levels. Optimal experimental design minimizes “noise” in data to allow focus on the influence on assay response of critical factors. A factorial experiment (DOE) may minimize experiments required to achieve analytical purpose. (May be modified with complete block, factorial, fractional factorial, full factorial, incomplete block). (TR57)
Destructive
A method in which a sample cannot be subsequently utilized in any other analytical method or processed to a final product. (TR86)
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Detectability
The ability to discover or determine the existence, presence, or fact of hazard. (TR54) (TR54-5)
The ability to discover or determine the existence, presence, or fact of a hazard (6). For purposes of this technical report, a hazard typically would be a data integrity breach.(TR84)
Detectability (D)
The ability to discover or determine the existence, presence, or fact of a hazard. (TR54-2) (TR54-3)
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Detection
The ability to discover or identify a defect or failure. (TR44)
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Detergent
A synthetic wetting agent and emulsifier that can be added to a solvent to improve its cleaning efficiency. (TR70)
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Deterministic Leak Test Method
A method in which the leakage event being detected or measured is based on phenomena that follow a predictable chain of events. In addition, the measure of leak detection is based on physicochemical technologies that are readily controlled and monitored, yielding objective quantitative data. (TR86)
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Development Reports
Documentation and description of work done during the early phases of development. The goal is to document information about the way the process works and to document why key choices were made in selecting the specifics of the process (e.g., flow rate or temperature). These documents can serve as a reference during investigations of discrepancies and during the design of specific Validation and characterization studies.(TR14) (TR 42)
Documentation and description of work done during the early phases of development (Stage 1). The goal is to document information about the way the process works and to document why key choices were made in selecting the specifics of the process (e.g., flow rate or temperature). These documents can serve as a reference during investigations of deviations and during the design of specific validation and process characterization studies.(TR60)
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Deviation
Departure or digression from set parameters. (TR58)
Data or a result outside of the expected range or an unfulfilled requirement; it may be called nonconformity, defect, discrepancy, out-of-specification, out-of-limit, or adverse trend. (TR88)
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Dew Point
The temperature at which a vapor or vapors become saturated. (TR51) The temperature to which a given parcel of humid air must be cooled, at constant barometric pressure, for water vapor to condense into water. The condensed water is called dew. The dew point is a saturation temperature. The dew point is associated with Relative Humidity (RH). A high RH indicates that the dew point is closer to the current air temperature. RH of 100% indicates the dew point is equal to the current temperature and the air is maximally saturated with water. When the dew point remains constant and temperature increases, RH will decrease. (TR55)
Dextrans
Complex, branched, high molecular weight polysaccharides made of many glucose molecules joined into chains of varying lengths and branches. (TR41)
Diafiltration
The convective elimination of permeable solutes by the addition of fresh solvent to the retentate. (TR15)