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PDA Glossary

PDA Glossary of Pharmaceutical and Biotechnology Terminology

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.

Browse Terms by Title

 

Browse Terms by TR #

 
 
  • 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)

  • Acceptance Criteria

    Numerical limits, ranges, or other suitable measures for acceptance of test results. (TR 14) (TR 29) (TR 38) (TR 64)

    Numerical limits, ranges, or other suitable measures for acceptance of test results. Exceeding the acceptable range for a critical parameter during subsequent validation studies may result in questionable product quality that would require initiation of an investigation. Exceeding the operating range should be documented and explained in the validation report and evaluated for validation study impact. (TR 42)

    The pre-defined specifications, standards or ranges that must be met under stated test conditions. (TR 48)

    Numerical limits, ranges, or other suitable measures for acceptance of the results of analytical method validation that is satisfied to determine suitability of test method performance.(TR 57) (TR 69) (TR 72) (TR 74)

    The criteria that a system or component must satisfy in order to be accepted by a user or other authorized entity. (TR 54-5)

  • Acceptance Limit

    The maximum amount of residue allowed in a product, in an analytical sample, or as an amount per surface area. (TR29)

  • 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)

  • Acholeplasma laidlawii

    A. laidlawii is a mycoplasma in class Mollicutes and order Acholeplasmatales. (TR75)

  • 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)

  • 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)

  • 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)

  • Action Plan

    A written plan consisting of elements to be accomplished to achieve a specific result. The plan describes responsibility for each element and a target date for completion. (TR22)

  • Active Pharmaceutical Ingredient (API)

    Synonym: Drug Substance. (TR14) (TR42)

    A substance or mixture of substances that, when delivered in a finished drug product, directly affects the structure or function of the body. (TR54-4)

    Any substance or mixture of substance intended to be used in the manufacture of a drug (medicinal) product and that, when used in the production of a drug, becomes an active ingredient of the drug product. Such substances are intended to furnish pharmacological activity or other direct effect in the diagnosis, cure, mitigation, treatment, or prevention of disease or to affect the structure and function of the body. Note: also known as Drug Substance. (TR29) (TR56) (TR41) (TR54-3) (TR60)

    Any substance or mixture of substances intended to be used in the compounding of a drug preparation, thereby becoming the active ingredient in that preparation and furnishing pharmacological activity o other direct effect in the diagnosis, cure, mitigation, treatment, or prevention of disease in humans and animals or affecting the structure and function of the body. (TR63) (TR70)

    Any substance or mixture of substances intended to be used in the manufacture of a drug product, and that when used in the production of a drug, becomes an active ingredient in the drug product. Such substances are intended to furnish pharmacological activity or other direct effect in the diagnosis, cure, mitigation, treatment or prevention of disease, or to affect the structure and function of the body. (TR74)

  • Active Pharmaceutical Ingredient (API) Equivalent to Drug Substance for large molecules

    Any substance or mixture of substances intended to be used in the manufacture of a drug (medicinal) product and that, when used in the production of drug, becomes an active ingredient of the drug product. Such substances are intended to furnish pharmacological activity or other direct effect in the diagnosis, cure, mitigation, treatment, or prevention of disease or to affect the structure and function of the body. (TR60)

  • Active Pharmaceutical Ingredient (API) or (Drug substance)

    Any substance or mixture of substances intended to be used in the manufacture of a drug (medicinal) product and when used in the production of a drug, becomes an active ingredient of the drug product (also called “drug substance”). (TR29)

    Any substance or mixture of substances intended to be used in the manufacture of a drug (medicinal) product and that, when used in the production of a drug, becomes an active ingredient in the drug product. Such substances are intended to furnish pharmacological activity or other direct effect in the diagnosis, cure, mitigation, treatment, or prevention of disease or to affect the structure and function of the body. (TR54-3)

    Any substance or mixture of substances intended to be used in the compounding of a drug preparation, thereby becoming the active ingredient in that preparation and furnishing pharmacological activity or other direct effect in the diagnosis, cure, mitigation, treatment, or prevention of disease in humans and animals or affecting the structure and function of the body. (TR63)

  • Active Pharmaceutical Ingredient (API) Starting Material

    A raw material, intermediate, or an API that is used in the production of an API and that is incorporated as a significant structural fragment into the structure of the API. An API Starting Material can be an article of commerce, a material purchased from one or more suppliers under contract or commercial agreement, or produced in-house. API Starting Materials normally have defined chemical properties and structures. (TR60)

  • Activity

    Ability of endotoxin (LPS) to initiate the LAL cascade in the compendial bacterial endotoxins test (BET) assay, or the ability to elicit a pyrogenic response in a compendial pyrogen test (2,10). Activity can be measured by other assays such as the monocyte activation test (MAT) or recombinant Factor C tests (rFc), if such tests have been validated, to demonstrate that decisions made from the results are comparable to or superior to the compendial assay. Activity is measured in endotoxin units (EU). In terms of activity, one EU = one IU, regardless of the source. Activity is generally expressed as a concentration, usually EU/mL.(TR82)

  • Adsorption

    Retention of solutes, suspended colloidal particles or microorganisms to fluid contact surfaces, e.g., the surfaces of pores in the filter medium. (May be modified with the following terms: electrokinetic, charge-rated, surface charge, hydrophobic or ionic strength. (TR45)

    The retention of solutes, suspended colloidal particles or microorganisms to fluid contact surfaces, e.g., the surfaces of pores in filtration membranes. (TR26)

  • 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)
  • 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)

  • Adventitious Virus

    An exogenously introduced infectious virus that is unintentionally present in a biological product or its manufacturing process. (TR71) (TR83)

  • Adverse Drug Reaction (ADR)

    The American Society of Hospital Pharmacists (ASHP) defines a significant ADR as any unexpected, unintended, undesired, or excessive response to a drug that:
    (1) Requires discontinuing the drug (therapeutic or diagnostic) Requires changing the drug therapy
    (2) Requires modifying the dose (except for minor dosage adjustment)
    (3) Necessitates admission to a hospital
    (4) Prolongs stay in a healthcare facility
    (5) Necessitates supportive treatment
    (6) Significantly complicates diagnosis
    (7) Negatively affects prognosis
    (8) Results in temporary or permanent harm, disability, or death.
    The World Health Organization (WHO) defines ADR as any noxious, unintended, and undesired effect of a drug which occurs at doses used for prophylaxis, diagnosis, or therapy, excluding therapeutic failures, intentional and accidental overdose and drug abuse. It does not consider errors in drug administration to be adverse events. (TR55)

  • 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)

  • 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)

  • 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)

  • Air Detector

    A moist heat sterilization process that operates at a controlled pressure greater than saturated steam pressure and typically uses compressed air to bring the chamber to the desired pressure. (TR01) (TR48)

  • Air Overpressure Sterilization Process

    A moist heat sterilization process that operates at a controlled pressure greater than saturated steam pressure and typically uses compressed air to bring the chamber to the desired pressure. (TR01) (TR48)

  • 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)

  • Airborne Particulate Count (Total Particulate Count)

    The total number of particles of a specific size per unit volume of air. (TR13)

  • Airborne Viable Particulate Count (Total Airborne Aerobic Microbial Count)

    The total number of particles of a specific size per unit volume of air. (TR13)

  • Airlock

    A room that controls the airflow between two rooms of different classification. (TR 70)

  • 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)

  • 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)

  • 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)

  • 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)

  • Anaerobe

    An organism that has the ability to grow in the absence of oxygen. (TR51)

  • Anaerobic Microorganism

    A microorganism that does not utilize oxygen as the final electron acceptor during metabolism; microorganism that will grow only in the absence of oxygen. (TR62)(TR22)

  • Analysis of Variance (ANOVA)

    A general statistical approach to data analysis (i.e., comparison of means) in which the variation in a method’s results is partitioned among explanatory factors in order to systematically assess factor influence and/or variance components. (TR57)

  • Analyte

    Substance (usually a residue) for which an analysis is being performed. (TR29) (TR49) (TR70)

    A specific chemical moiety being measured, which can be intact drug, biomolecule or its derivative, impurity, and/or excipients in a drug product. [Synonym: measurand] (TR57)

  • Analytical Control

    Material used to monitor the performance of a method to assess the integrity and validity of the results. (TR57-2)

  • Analytical Instrument Qualification (AIQ)

    The qualification of the analytical instrument(s) used as part of the analytical procedure. (TR57)

  • Analytical Method Comparability (AMC)

    Equivalence study that measure the same property of two methods and that shows that replacing one of these methods with the other would not adversely affect the test’s use or results. (TR57-2)

  • Analytical Method Design

    Collection of activities performed to define the intended purpose of the method, select the appropriate technology to implement the method, and identify the critical method variables that need to be controlled to ensure that the method is robust and rugged. (TR57-2)

  • Analytical Method Development (AMD)

    Collection of activities performed to select an appropriate technique and method conditions to meet the Analytical Target Profile (ATP) requirements. (TR57-2)

  • Analytical Method Qualification (AMQ)

    Formal or informal study performed to assess initial method performance prior to full ICH Q2(R1) validation; assessment activity that culminates in a scientifically sound method that has an acceptable level of performance, is documented to be suitable for its intended use, and is demonstrated to have “adequate capability … to meet appropriate standards of performance for its purpose” (TR57-2)

  • Analytical Method Transfer (AMT)

    Documented process that qualifies a laboratory (receiving unit) to use an analytical test procedure that originates in another laboratory (the transferring unit, also known as the sending unit), thus ensuring that the receiving unit has the knowledge and ability to perform the transferred analytical procedure as intended. (TR57-2)

  • Analytical Platform Technology (APT)

    An analytical method that is used for multiple products and/or types of sample matrix without modification of the procedure. Similar to compendial methods, an APT method may not require full validation for each new product or sample type. (TR57)

  • Analytical Procedure

    That which is performed in order to obtain a reportable result. The procedure should describe in detail the steps necessary to perform the analytical test. This may include but is not limited to: the sample, the reference standard and the reagents preparations, use of the apparatus, generations of the calibration curve, use of the formulae for the calculation [Synonym: Method, Assay] (TR57)

  • Analytical Target Profile (ATP)

    Set of predefined method parameters and performance requirements that help identify the type of method desired relative to method categories (identity, purity, and impurity) defined in ICH Q2(R1) as well as the necessary method performance attributes, such as accuracy, precision, and specificity. (TR57-2)

  • Annealing Temperature

    A temperature designed to allow primers to attach to single-stranded DNA or RNA to initiate amplification. The annealing temperature is usually kept a few degrees lower than the melting temperature of the primers to avoid non-specific amplification. See “Melting Temperature”. (TR50)

  • Antimicrobial Chemical Agent

    Substance used to destroy or suppress the growth of microorganisms, whether bacteria, fungi, or viruses, on inanimate objects and surfaces. (TR70)

  • Area Disinfection

    Disinfection of floors, walls, ceilings, and other surfaces. (TR70)

  • Aseptic (Asepsis)

    Free from disease-producing microorganisms. (TR28)

    Free from disease-producing microorganisms. An operation performed in a controlled environment designed to prevent contamination through the introduction of microorganisms. (TR26)

  • Aseptic Filling

    The part of aseptic processing where a pre- sterilized product is filled and/or packaged into sterile containers and closed. (TR22) (TR28) (TR62) (TR13)

  • Aseptic Process

    A process in which sterile materials are handled in an environment in which the air supply, materials, equipment and personnel are controlled to prevent microbial and particulate contamination. (TR44) (TR51)

  • 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)

  • 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)

  • Aseptic Processing Simulation (APS)

    A means for establishing the capability of an aseptic process as performed using a growth medium. (TR22) (TR62)

  • Attachment (Adhesion)

    Discrete association of a microorganism with an animate or inanimate surface. (TR69)

  • Atypical Particles (AP)

    Particles that should not be present in excipients, APIs, intermediates, and final oral dosage forms, and their presence should always trigger an investigation. These particles consist of foreign matter that is not intended/designed to be in direct contact with the product/manufacturing process. These particles commonly originate from materials which accidently or unintentionally come into contact with the product or a process stream. (TR78)
  • Automated Inspection

    Consists of mechanical handling and presenta­tion of product containers combined with auto­mated inspection of the filled containers using image analysis and/or light obscuration. (TR79)

  • Back Pressure

    Residual pressure opposing the free flow of liquid or gas at the outlet side of the filter. (TR45)

    Pressure applied downstream of a filter or other piece of equipment. (TR26)

  • Bacteria

    Single-celled, microscopic organisms typically with a cell wall and characteristic shape (e.g., round, rod-like, spiral or filamentous); lacking a defined nucleus (“prokaryotic”). (TR26)

  • Bacterial Endotoxin

    Endotoxins are fever producing substances commonly found in the cell wall of certain Gram-negative bacteria. (TR3)

  • 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)

  • Bacteriophage

    A bacteriophage is any one of a number of viruses that infect bacteria. The term is commonly used in its shortened form, “phage”. (TR41) (TR 47)

  • Ballotini

    Small glass beads (spheres) obtainable in a range of sizes, used in the recovery of spores from paper carriers. (TR51)

  • Batch Filtration Process

    In a batch filtration process, the entire volume to be filtered is held in a single feed tank. The retentate stream is recycled back to that single feed tank. (TR15)

  • Batch Oven

    A convection oven with a chamber or chambers where items are dry-heat sterilized or depyrogenated as a single load in a discontinuous process. The oven typically uses one or more filters to remove air particles. (TR3)

  • Batch Process

    A process where there are no streams flowing into or out of a controlled volume, as opposed to a continuous process. In a batch filtration process, the feed solution is reduced in volume due to permeation of filtrate through the filter. There is no continuous addition of feed solution to the feed vessel. (TR45)

  • Beta Glucans [(1→3)-β-D-glucans] (BG)

    Homopolymers of glucose connected by (1→3)-β-D- glycosidic linkages. (TR45)

  • 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)

  • Bioanalytical Test Method

    A method used to assess the presence of analytes (chemical or biological) in biological samples (e.g., serum, plasma, etc.). (TR57)

  • 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)

  • 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)

  • Biocide

    Chemical substance that has been proven to kill specific microorganisms common in the pharmaceutical manufacturing environment. (TR 69)

  • Biofilm

    Microbially derived sessile community characterized by cells that are irreversibly attached to a substratum, interface, or each other; are embedded in a matrix of extracellular polymeric substances (EPSs) that they produce; and exhibit an altered phenotype with respect to growth rate and gene transcription. (TR 69)

  • Biofouling (or Biological Fouling)

    Accumulation and subsequent deleterious effects of biological contaminants on engineered products or processes (TR 69)

  • Biological Active Substance

    Manufactured biological active substances and medicinal products involving biological process­es and materials, such as cultivation of cells or extraction from living organisms. (TR56)

  • Biological Activity

    Property that describes the specific ability or capacity of a product to achieve a defined biological effect. (TR57)

  • 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)

  • Biological Indicator (BI) Challenge System

    A test system containing viable microorganisms of a pure and specified strain providing a defined resistance to a specified sterilization process (TR1)(TR3) (TR30) (TR61)

  • 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)

  • 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)

  • 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)

  • Biological Tests

    Biological tests include animal, cell culture, or biochemical based testing that measures a biological, biochemical, or physiological response. (TR38)

  • 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)

  • 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)

  • Blocking

    The grouping of related experimental units used in design of experiments (DOE). (TR57)

  • Boundary Layer

    A thin layer of fluid near the membrane surface in which the tangential velocity changes from zero at the surface to the free stream value away from the surface. (TR15)

    Coating of fluid in the immediate vicinity of a bounding surface where the effects of viscosity are significant (TR 69)

  • Bracketing

    A demonstration of unit operation performance at two different values of a given parameter (e.g., ionic strength, dwell time or temperature), allowing the use any values of that parameter falling within this range. (TR41)

  • Bracketing Approach

    A scientific approach for defining product/load characteristics (e.g., viscosity, container sizes, container fill volumes, item sizes, loading configurations) that are tested (in a qualification study or validation study) at upper and/or lower limits. (TR1) (TR61)

    A validation method that tests the extremes of a process or product. The method assumes the extremes will be representative of all the samples between the extremes. (TR26)

  • Break-loose Force

    Energy required to initiate plunger movement within the syringe barrel upon injection. (TR 73)

  • Breakthrough Limited

    A filtration operation resulting in a significant rise in filtrate turbidity accompanied by a small increase in differential pressure. This occurs when the adsorptive capacity of the filter is reached, resulting in the passage of particles smaller than the pore size of the filter that would normally be removed by adsorption. (TR45)

  • Brevundimonas Diminuta (B. diminuta)

    Small bacteria (0.3–0.4 &;mum in diameter by 0.6–0.1 &;mum long) used to challenge a sterilizing grade filter during validation testing. [Formerly Pseudomonas diminuta](TR45)

  • 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)

  • Carrier

    A solid support upon which the test organism used in biological monitoring is inoculated. (TR51)

  • 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)

  • Cell Substrate

    The host cells that are used to propagate or detect viruses. (TR 47)

    Cells used for the manufacture of a biological medicinal product. (TR 71) (TR 83)

  • Cells at Limit of invitro Cell Age Used for Production

    Cells used for production which are at the limit of their invitro cell age. Note Also known as, “End-of-Production-Cells”. (TR56)

  • CFU: Genome Copy Ratio

    The relationship between the number of colony forming units counted on solid media and the number of genome copies measured using a method suitable for quantitative assessment of genomic DNA. (TR50)

  • Challenge Concentration

    The concentration in Colony Forming Units/mL of the test microorganism in the challenge fluid. (TR75)

  • Challenge Fluid

    The carrier fluid in which the test microorganism is suspended and delivered to the test filter. (TR75)

  • Challenge Level

    The concentration of the test microorganism applied to the test filter (per centimeter squared) or the total number of cells applied to the test filter at the completion of the challenge. (TR75)

  • Challenge Volume

    The volume of challenge fluid applied to the test filter. (TR75)

  • 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)

  • 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)

  • Chemistry Manufacturing and Controls (CMC)

    The body of information that defines the technical development, manufacturing facility and support utilities; the process equipment and materials used in manufacturing; the manufacturing process itself; the personnel involved in manufacturing and qual­ity; the chemistry of the product; QC in process and release testing, specifications, and stability of the product; all of the controls, documentation, and training necessary to ensure that all of these listed ac­tivities are properly and effectively carried out. (TR56)

  • Coefficient of Determination (r²)

    A measure of the proportion of the variation of one variable determined by the variation of the other. (TR57)

  • Colonization (Microbial)

    Growth (division) of adherent microorganisms on a surface (TR 69)

  • Colony Forming Unit (CFU)

    One or more microorganisms that produce a visible, discrete growth entity on a semi-solid, agar-based microbiological medium. (TR22) (TR62)

    Visible outcome of growth of microorganisms arising from a single or multiple cells. (TR28)

    A single microorganism or an aggregate of many that forms a single discrete colony on solid agar media after suitable incubation. Colony forming units are used for bacterial titer (total bacteria load in a sample) determination on solid media. (TR50) (TR75)

  • Color Changing Unit (CCU)

    The quantity of mycoplasma contained in the highest dilution of a test article that produces a color change in a pH-sensitive liquid medium (typically containing phenol red) within a specified time of incubation, used for end-point determination of growth. (TR50)

  • Column Load

    The solute that is passed through the column for separation. (TR14)

  • Column Packing

    Preparation of a column that includes the addition of resin slurry into a column to create a bed suitable for its intended use. Characteristics of a packed column bed include bed height and diameter, backpressure, and number of theoretical plates. (TR14)

  • Contact Time

    The minimum amount of time that a sanitizer, disinfectant, or sporicide must be left in complete (wet) contact with the surface to be treated in order to be effective. (TR70)

  • 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)

  • Contamination Rate

    The percentage of units filled in a process simulation that are positive for microbial growth after incubation. (TR22)

  • Continuous Convection Tunnel

    A convection oven with a conveyor belt that transports articles through several temperature zones that are supplied with heated forced HEPA filtered air. The pre-heat/loading zone warms articles prior to the heat zone, the heat zone heats articles to sterilization or depyrogenation temperature and the cool zone cools articles prior to conveyance out of the unit. [Synonym: Tunnel Sterilizer] (TR3)

  • Correlation Coefficient ( r )

    A measure of covariation, the square root of the coefficient of determination. (TR57)

  • 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)

  • Co-Validation

    Sending and receiving laboratories participate in the AMV study execution. (TR57)

  • Coverage

    The appropriate distribution of a chemical agent needed on the equipment surface to be effective. (TR70)

  • Critical Aspect Design Elements (CADE)

    Critical aspect design elements are components, instruments, and process controls that comprise the critical aspect (e.g., temperature feedback loop). Critical aspect design elements are tested in commissioning and qualification. (TR54-5)

  • Critical Aspects (CAs) of Manufacturing Systems

    Critical aspects are constituent parts of a system or piece of equipment that provide the ability to control one or more critical process parameter of the associated process (e.g., temperature control­ler of a bioreactor). (TR54-5)

  • 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.

  • Culture Medium

    The nutritional medium which supports the growth of the given microorganism. (TR75)

  • Cycle Development

    A series of activities performed for the purpose of defining or confirming the cycle parameters (e.g., time, temperature, pressure) necessary to ensure sanitization or sterilization. (TR61)

  • Cycle Phases

    A discrete series of sterilizer process steps (such as, heat-up, exposure and cool-down) performed sequentially that represent a complete sterilization cycle. (TR48)

  • 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)

  • Cytopathic Virus

    Viruses where infection of cells results in microscopically visible degeneration of the cells or other morphological changes. (TR47)

  • Darcy Permeability

    The constant of proportionality of the material as defined by Darcy’s Law. (TR45)

  • 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)

  • De Novo Sequence Assembly

    Assembly of short reads of a sequence to generate a contiguous sequence (contig). (TR71)

  • Dead Leg

    Area of entrapment in a vessel or piping run that could lead to contamination of the product. (TR69)

  • 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)

  • Decontamination

    A process that is designed to remove soil (including microorganisms) and may consist of cleaning and/or disinfection. (TR51)

  • 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)

  • 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)

  • 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)

  • Detergent

    A synthetic wetting agent and emulsifier that can be added to a solvent to improve its cleaning efficiency. (TR70)

  • Dextrans

    Complex, branched, high molecular weight polysaccharides made of many glucose molecules joined into chains of varying lengths and branches. (TR41)

  • Dirty Hold Time

    The time from the end of product manufacturing until the beginning of the cleaning process (also called “soiled hold time”). (TR29)

  • Disinfectant

    A chemical or physical agent that reduces, destroys, or eliminates vegetative forms of harmful microorganisms but not spores. (TR70)

  • Disinfection

    The destruction of pathogenic and other kinds of microorganisms by thermal or chemical means. (TR51) (TR70)

    Process of eliminating nearly all recognized pathogenic microorganisms but not necessarily all microbial forms (e.g., bacterial spores) on inanimate objects. (TR69)

    The chemical or physical inactivation of a bioburden on inanimate surfaces. Typically this requires a minimum three-log (3-log) reduction of vegetative microorganisms and two-log (2-log) reduction for bacterial spore be achieved in validation. (TR13)

  • Downstream Side (of Filter)

    The effluent side of the process step (filter). (TR45)

    The filtrate or outlet side of the filter. (TR26)

  • Dry Equipment

    No visible water in the equipment or line when viewed under appropriate lighting conditions. (TR29) No visible water pool evident in the equipment or line when viewed under appropriate lighting conditions. (TR49)

  • Dryness Fraction

    An absolute measure of the actual latent heat of a sample of steam relative to the theoretical latent heat of saturated steam. (TR01) (TR48)

  • Dryness Value

    A dimensionless test quantity developed to approximate the dryness fraction. (TR01)

  • 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)

  • 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)

  • 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)

  • Dwell Time

    The period that items are subjected to a given processing condition. [Synonym: Residence Time] (TR3)

  • Dynamic Light Scattering (DLS)

    A technique used to measure the size and size distribution of particles. Particles suspended in a solution will cause scattering of light and the extent of the scattering is related to the size and shape of the particles. (TR47)

  • Early Phase

    Generally used to indicate Phase 1 and A clinical studies.(TR 56)
  • Emulsions

    A dispersed colloidal system consisting of two immiscible liquid phases generally stabilized with one or more suitable agents. Injectable emulsions are sterile liquid dosage forms of drug substances dissolved or dispersed in a suitable emulsion me­dium. Injectable emulsions are for parenteral ad­ministration of poorly water-soluble drugs. (TR79)

  • Endogenous Virus

    A virus that pre-exists in the genome of the cell substrate. (TR71)

    A virus that integrates into the genome of the cell substrate. (TR83)

  • Endogenous Virus-Like Particles – (e.g., Type C endogenous retroviruses)

    Virus-like entity whose genetic material is stably integrated into the germ line of an organism or cell line. Cell lines (notably CHO) may constitutively produce virus-like particles, which are typically noninfectious but still of safety concern. Model retroviruses are generally used as surrogates to measure virus-like particle clearance. (TR41)

  • Endospore

    A type of spore formed intracellularly by some bacterial genera. (TR51)

  • Endotoxin

    Lipopolysaccharides from the cell walls of bacteria, the most potent of which derive from Gram-negative organisms. When injected, they are known to cause a febrile, or fever-producing reaction that can cause severe patient reactions, and on occasion, can be fatal. (TR26) (TR44)

    Pyrogenic lipopolysaccharide component of Gram-negative bacterial cell walls. (TR69)

  • Endotoxin Indicator (EI) for Depyrogenation

    An article challenged with a vial of endotoxin (or a carrier spiked with endotoxin) designed for use in depyrogenation studies. The endotoxin (a purified lipopolysaccaride) is validated for use in or on an endotoxin indicator. The carrier is made from a material appropriate for the intended depyrogenation processes to which it will be subjected. The endotoxin on a carrier is added at a concentration sufficient to allow recovery of a minimum of 1000 USP endotoxin units/carrier. The endotoxin indicator would allow for accurate indication of at least a 3-log reduction in USP endotoxin units during depyrogenation process challenges. (TR3)

  • Endpoint PCR

    A classical PCR method based on repeated cycling of the reaction mixture between two or three temperatures (denaturing, annealing, and extension) with detection of the amplified product after reaction completion (e.g., by agarose gel electrophoresis). (TR50)

  • Environmental Flora (isolates)

    Microorganisms associated with a processing environment. (TR22)

  • Environmental Monitoring (EM)

    Describes the processes and activities that need to take place to characterize and monitor the quality of the environment. (TR70)

  • Environmental Monitoring Program

    Defined documented program which describes the routine particulate and microbiological monitoring of processing and manufacturing areas, and includes a corrective action plan when action levels are exceeded. It includes assessment of environmental air, surfaces and personnel. (TR22) (TR28) (TR62)

  • Enzyme-Linked Immunosorbent Assay, or ELISA

    A biochemical technique used to detect or measure the presence of an antibody or an antigen in a sample. (TR41) (TR47)

  • Exclusivity

    The capacity of an assay not to detect microorganisms closely related to a target microorganism. (TR33)

  • Exotoxin

    Lipopolysaccharides from the cell walls of bacteria, the most potent of which derive from Gram-negative organisms. When injected, they are known to cause a febrile, or fever-producing reaction that can cause severe patient reactions, and on occasion, can be fatal. (TR26) (TR44)

    Pyrogenic lipopolysaccharide component of Gram-negative bacterial cell walls.(TR69)

    The major constituent of the outer membrane of Gram-negative bacteria is composed of lipid A, the core polysaccharide, and the O-antigen polysaccharide; endotoxin is also known as lipopolysaccharide (LPS).(TR82)

  • Extracellular Polymeric Substance (EPS)

    Product of microbial growth, particularly in biofilms, composed of polysaccharides, lipids, proteins, and nucleic acids; produced by bacteria and fungi; is an important mediator of microbial attachment to surfaces and biofilm formation. (TR69)

  • Extraction Control

    A known test article processed with a nucleic acid extraction procedure in order to ensure the proper extraction of nucleic acid. (TR50)

  • Extraction Recovery

    The efficiency of extraction of target analyte from a test matrix. It is usually measured as ratio (percentage) of analyte amount extracted from the matrix to that originally present in the matrix before extraction. (TR50)

  • F0

    <p>A term used when the specific reference conditions of T<sub>ref</sub>- = 121.1&deg;C and z = 10&deg;C are used to calculate the equivalent lethality. For example, when the z-value of the BI is 10&deg;C, a cycle with an F(T=121.1&deg;C, z=10&deg;C), or F<sub>0</sub>, equal to 8 minutes is equivalent (in terms of delivered lethality) to a square wave cycle of 8 minutes at 121.1&deg;C. A square wave cycle that provided an exposure of 25.9 minutes at 116&deg;C would also yield an F<sub>0</sub> of 8 minutes.   Note: The reference temperature used in calculating F<sub>0</sub> is 121.1&deg;C, which is the approximate mathematical equivalent of 250°F. (TR01) (TR30) (TR48) (TR61)</p>
  • False Negative

    A test result that is erroneously classified in a negative category (e.g., the absence of a viable microbial detection result when viable microorganisms are present). (TR33)

  • False Positive

    A test result that is erroneously classified in a positive category (e.g., a viable microbial detection result when viable microorganisms are not present). (TR33)

  • Fastidious strain (isolate)

    A population of microorganisms having complex nutritional requirements and thus difficult to cultivate. (TR50)

  • Fermentation Broth

    The fluid and all constituents in a fermentation vessel prior to separation. (TR45)

  • First Air

    Refers to the air exiting at the face of HEPA filters. Based on the airflow through HEPA filters and its unidirectional air flow the air exiting at the filter face is for the purposed of aseptic processing free of particulate contamination (both viable and non-viable). (TR70)

  • First Air (First Work Location)

    The work location first in the path of HEPA filtered air. (TR62)

  • Focus Forming Unit (FFU)

    A measure of virus infectively based on formation of a region or “focus”, of infected cells within a monolayer culture that is caused by viruses that do not kill their host, but rather transform them. The number of foci is directly correlated to the number of infectious virus particles. (TR47)

  • Fraction-Negative Methods

    Fraction-negative methods use the starting population of a biological indicator (N0) and data in the quantal range to create a two-point line from which the DT-value can be determined. The quantal range is the exposure period over which a set of replicate test units exhibit a dichotomous response – some are positive for growth and the rest are negative for growth. (TR01)

  • Frank (Canonical) Pathogens

    Microorganisms responsible for infection in healthy individuals (i.e., individuals with normal operative and functional host defense mechanisms) that may be acquired from exposure to other infected people or animals, environmental reservoirs (exogenous) or the individual’s normal (endogenous) microbial flora. (TR67)

  • Free Drained Equipment

    No visible water pool in the equipment or line when viewed under appropriate lighting conditions (but may contain water droplets). (TR29)

  • F-Value (Lethality Factor)

    A measurement of sterilization effectiveness, the F-value is the calculated equivalent lethality (using a specified z-value), in terms of minutes at a reference temperature (Tref), delivered by a sterilization cycle. (TR1) (TR3) (TR30) (TR48) (TR61)

  • F-Value (Lethality Factor) -- FBiological

    A term used to describe the delivered lethality, measured in terms of actual kill of microorganisms on or in a BI challenge system. The FBiological-value is calculated as DT × LR, where DT is the D-value of the BI system at the reference temperature (T) and LR is the actual logarithmic reduction (log N0 – log NF) of the BI population achieved during the cycle. (TR1)

  • F-Value (Lethality Factor) -- FO

    A term used when the specific reference conditions of Tref = 121.1°C and z = 10°C are used to calculate the equivalent lethality. For example, when the z-value of the BI is 10°C a cycle with an F(T=121.1°C, z=10°C), or F0, equal to 8 minutes is equivalent (in terms of delivered lethality) to a square wave cycle of 8 minutes at 121.1°C. A square wave cycle that provided an exposure of 25.9 minutes at 160deg;C would also yield an F0 of 8 minutes. (TR1)

  • F-Value (Lethality Factor) -- Fphysical

    A term used to describe the delivered lethality calculated based on the physical parameters of the cycle. The FPhysical-value is the integration of the lethal rate (L) over time. The lethal rate is calculated for a reference temperature (Tref-) and z-value using the equation: L = 10(T-Tref- )/z. (TR1)

  • F-Value (Lethality Factor) -- F-Value for Depyrogenation

    The term F-value may also be used in dryheat depyrogenation processes to calculate the time in minutes equivalent to a lethality or endotoxin destruction effect delivered by dry heat at 250°C. The F-value reference temperature is set at 250°C and the z-value minimum is set at 46.4°C. (TR3)

  • F-Value (Lethality Factor)-- FH

    A term used when the specific reference conditions of Tref = 160°C and z=20°C are used to calculate the equivalent lethality. For example, when the z-value of the BI is 20°C a process with an F(T=160°C, z=20°C), or FH, equal to 8 minutes is equivalent (in terms of delivered lethality) to a square wave process of 8 minutes at 160°C. A square wave process that provided an exposure of 45.2 minutes at 145°C would also yield an FH of 8 minutes. (TR3)

  • Gamma Irradiation

    The process by which a material is rendered sterile by exposing the material to a radioactive source, such as Cobalt 60. (TR70)

    Ionizing radiation that can be used to sterilize a material. (TR26)

  • Gels

    Gels (sometimes called jellies) are semisolid sys­tems consisting either of suspensions of small inorganic particles or of organic molecules inter­penetrated by a liquid. Gels can be classed either as single-phase or two-phase systems. (TR79)

  • Genetic Marker

    A gene or DNA sequence within a chromosome which can be used for discrimination of one mycoplasma species or strain from another. (TR50)

  • Genome Copy (GC)

    An amount of nucleic acid equivalent to the genetic complement present in the genome of a single microorganism. (TR50)

  • Genotypic

    Relating to those characters that reside in the genetic complement of a specific strain of a specific organism. (TR51)

  • Germicide

    A compound that destroys all vegetative microorganisms. (TR70)

  • Gram Positive

    An organism that retains the Gram stain. (TR51)

  • Gravity Displacement

    A sterilization process based on the principle that cold air within the chamber is heavier than the steam entering and will sink to the bottom of the chamber. As steam enters the chamber, air is pushed out the bottom drain and exits, with the condensate, through a steam trap. (TR01) (TR48) (TR61)

  • Grouping Strategy

    A strategy for establishing similar cleaning processes, usually based on similar products or similar equipment, and to validate the cleaning process based primarily on validation data for a representative of the group. (TR29) (TR49)

  • Growth Promotion Test

    Test performed to demonstrate that media will support microbial growth. (TR22) (TR28)

  • Half-Cycle Qualification

    A qualification method that uses fifty percent of the exposure time to demonstrate sterilization cycle efficacy. The physical and biological lethality values achieved in the half-cycle exposure time are doubled to project the lethality that will be achieved by the full cycle.(TR01)

  • Harvest Testing

    The screening of a biopharmaceutical bulk cell culture harvest for any adventitious contaminants, including mycoplasma, before further processing. (TR50)

  • Heat-up Phase

    The phase of a sterilization cycle that occurs prior to the exposure phase. Process parameters are developed for this phase in order to meet applicable user requirements for load conditioning (e.g., air removal and preheating.) (TR01) (TR3) (TR48) (TR61)

  • Hemadsorption

    Adherence of red blood cells to virus-specific antigens on the surface of infected cells. In cellbased in vitro assays the reaction is used as an end point for virus detection. (TR47) (TR71)

  • Hemagglutination

    A clumping together or agglutination of red blood cells. In the context of this Technical Report hemagglutination indicates presence of virus that binds to erythrocytes. (TR47)

    The clumping of red blood cells by binding to virus particles. The hemagglutination reaction is used in cell-based in vitro assays as an end point for virus detection. (TR71)

  • High-Efficiency Particulate Air (HEPA) Filter

    A type of air filter that must satisfy certain standards of efficiency such as those set by the United States Department of Energy (DOE). The air filter must remove 99.97% of all particles greater than 0.3 micrometer from the air that passes through it. (TR62) (TR70)

  • Hybridization

    The formation of a double-stranded complex of complementary strands of nucleic acids (e.g., a primer and single-stranded DNA or RNA) (TR50)

  • Inclusivity

    The ability of an assay to detect a target microorganism. (TR33)

  • Indicator Cells

    Cell lines that are used in in vitro assays to detect the presence of viral agents. (TR71)

  • Infectious Unit

    A measure of quantity of infectious virus. An infectious unit does not necessarily reflect the number of virus particles, as virus preparations also contain noninfectious virus particles and, depending on the cellular host, more than one virus particle may be necessary to infect a cell. (TR47)

  • Inoculated Carrier

    A carrier upon which a defined number of test organisms have been deposited. (TR51)

  • Interference

    The capacity of a substance to affect the quantitation of virus in the assay. (TR47)

  • Intermediate Precision

    The precision within the same laboratory using different analysts, equipment, reagents and/or on different days. (TR33)

  • Internal Control

    A reaction performed to provide confirmation of adequate performance of the NAT assay including preparation of nucleic acid, its amplification using appropriate amplification technology, and analysis of amplified products. An example is the amplification of a housekeeping gene from the production cell line which provides a positive signal even in the absence of contaminant DNA. (TR50)

  • Intrinsic Particles

    Those particles that arise from sources related to the formulation, packaging, or assembly proces­ses. In each of these cases, the particle material (e.g., glass, stainless steel, rubber, or gasket ma­terial) could be identified as a known product-contact material. (TR78)

  • In-Use Testing (also called In-Situ Testing)

    A field study that validates the effectiveness of a disinfecting agent, the trained operators, and the approved operating procedures. (TR70)

  • In-vitro Transcribed RNA

    A RNA copy synthesized using a double-stranded DNA as template. The RNA polymerases of bacteriophage T7 or SP6 are usually used to perform the in-vitro transcription. (TR50)

  • Irradiation

    The process by which an item is exposed to ionizing radiation (typically gamma) to reduce or eliminate bioburden. (TR41)

  • ISO 5

    Environmental operating conditions defined in ISO 14644-1, “Cleanrooms and associated controlled environments”. (Note: For total particulates, ISO 5 approximates the Class 100 description from the now obsolete U.S. Federal Standard 2009 and is roughly comparable to Grade A as defined in European GMP Annex 1 – “Manufacture of Sterile Medicinal Products.”) (TR22) (TR62)

  • ISO 7

    Environmental operating conditions defined in ISO 14644-1, “Cleanrooms and associated controlled environments.” Note: For total particulates, ISO 7 approximates Class 10,000 from the now obsolete Federal Standard 209. (TR62)

  • ISO 8

    Environmental operating conditions defined in ISO 14644-1, “Cleanrooms and associated controlled environments.” Note: For total particulates, ISO 8 approximates Class 100,000 from the now obsolete Federal Standard 209. (TR62)

  • ISO/IEC

    International Organization for Standardization/International Electrotechnical Commision. (TR52)

  • Isolates

    Microorganisms that are recovered from a facility. (TR70)

  • Latent Virus

    Latency is the ability of a virus to be dormant (latent) within a cell (for example, genetic episomes; provirus). Under certain conditions the virus may become active and produce particles. (TR71)

  • Leak Rate

    Leak rate is the quantity of air leakage over time into the sterilizer chamber obtained while performing a chamber leak test. The leak rate should not exceed a level that will inhibit the sterilization process during air removal or vacuum drying stages. (TR03)

  • Leak Test

    See System Integrity Test. (TR61)

  • Limit

    A value for a residue above which a cleaning process would not be acceptable. (TR29) A value for a residue above which a cleaning validation protocol would fail. (TR49)

  • Limit of Detection (LOD)

    The lowest concentration of microorganisms in a test sample that can be detected, but not necessarily quantified, under the stated experimental conditions. (TR33)

    The lowest amount of analyte in a sample that can be distinguished from the absence of analyte. (TR41)

    The lowest concentration of analyte that can be unambiguously detected in a sample. For qualitative and for quantitative NAT methods, this value is conventionally expressed as a 95% positive cut-off value, representing the target concentration detected in 95% of repeated tests using a certain assay. (TR50)

  • Limit of Quantification

    The lowest number of microorganisms in a test sample that can be enumerated with acceptable accuracy and precision under the stated experimental conditions. (TR33)

  • Limit Sample

    An actual physical unit that is agreed to between the drug manufacturer and the glass manufacturer that defines the approximate maximum degree of acceptability for a specified non-conformance. Creation of limit samples between the user and the manufacturer is optional. (TR43)

  • Limit Test

    A quantitative test designed to give a positive/negative response. Ideally, a limit test has a high degree of specificity and a low limit of detection. (TR50).

  • Limit, Detection (DL)

    The lowest amount of analyte in a sample that can be detected but not necessarily quantitated as an exact value by an individual analytical procedure. [Synonym: Limit of detection (LOD)] (TR57)

  • Limit, Quantitation (QL)

    The lowest amount of analyte is a sample that can be quantitatively determined with suitable precision and accuracy by an individual analytical procedure. [Synonym: Limit of quantitation (LOQ)] (TR57)

  • Limiting Dilution

    In the context of this Technical Report the limiting dilution technique is used for virus cloning. The virus suspension is diluted until virus is no longer detectable. The dilution immediately before the dilution where infection of cells is no longer detectable is considered to contain only one virus particle or a very low number of virus particles. (TR47)

  • Limulus Amebocyte Lysate (LAL) Test

    Endotoxin detection and quantitation can be accomplished at high sensitivity and specificity using reagents manufactured from Limulus Amebocyte Lysate, a biological reagent prepared from horseshoe crabs and offered in a variety of formulations. (TR45)

  • Limulus Amoebocyte Lysate (LAL) Test

    A biologically based assay for the detection and quantitation of bacterial endotoxin. (TR69)

  • Linearity

    The ability to elicit results that are proportional to the concentration of microorganisms present in the sample within a given range, where accuracy and precision are demonstrated. (TR33)

    The linearity of an analytical procedure is its ability (within a given range) to obtain test results that are directly proportional to the concentration (amount) of analyte in the sample. (TR57)

  • Lipopolysaccharide

    A component of the cell wall of Gram-negative bacteria.(TR3)

    Component of the outer cell wall of Gram-negative bacteria that is pyrogenic. (TR69)(TR82)

  • Log Reduction

    Log reduction is defined as the first log being 90%, the second log being 9% and the third log being 0.09% of the original inoculums. (TR70)

  • Log Reduction Value (LRV)

    The logarithm to the base 10 of the ratio of organisms in the feed to organisms in the filtrate. (i.e., Log10(109/2) = 9.7). [Synonym: Log Titer Reduction] (TR45)

    Titer Reduction (TR) expressed as a base 10 logarithm. (TR75)

  • Log Titer Reduction (LTR) or Log Reduction Value (LRV)

    The virus reduction factor of an individual purification or inactivation step is defined as the log10 of the ratio of the virus titer or total load in the prepurification material and the virus titer or load in the post-purification material which is ready for use in the next step of the process. (TR41)

  • Low Endotoxin Recovery (LER)

    The inability to recover ≥50% activity over time when known amount of endotoxin is added to an undiluted product. LER cannot be overcome by dilution.(TR82)

  • Lyophilized (Product Cake)

    Freeze-dried product typically in the form of a solid plug or cake in the container. (TR79)

  • Magnetic Capture Hybridization (MCH)

    A purification method based on sequence-specific hybridization of labeled nucleic acid probes with targeted regions of test article nucleic acids, followed by magnetic bead capture. (TR50)

  • Mandrel

    Specialized filling needles on certain BFS machines which also act to form the container. (TR77)
  • Manual Baseline

    Data generated from visual inspection of a blind­ed set of seeded test containers that demonstrates the detection capability of human inspection. The test set is sometimes referred to as a “particle size threshold set,” where various foreign particu­late types in a gradation of sizes are examined to yield a statistically significant probability of de­tection percentage for each unit. This allows the determination of what types and sizes of particu­lates can be reproducibly detected in a specific product/container system. (TR79)

  • Manual Cleaning

    A cleaning procedure requiring operator-performed critical steps (e.g., scrubbing with a brush or rinsing with a hose). (TR70)

  • Manual Inspection

    Consists of manual handling and presentation of filled containers under controlled conditions of lighting and background to allow for human visual inspection. (TR79)

  • Manufacturing System

    The term system or systems represents equipment, facility, critical utilities, instruments, and other entities which perform the process or provide the conditions under which the process is performed. (TR54-5)

  • Masking

    A type of interference that may result in low endotoxin recovery.(TR82)

  • Matrix Spike Control

    An internal control in which an amplifiable amount of nucleic acid is added to a test article to determine inhibition of the PCR. This addition is usually performed pre-extraction and should provide a weak signal 100% of the time. Also known as “interference control”. (TR50)

  • Media

    The part of the filter through which fluid passes that retains particles during filtration. (TR45)

  • Media Fill

    See Aseptic Processing Simulation. (TR22)

  • Melting Temperature (Tm)

    The calculated or observed temperature for a primer/nucleic acid mixture at which 50% of primer-binding sites are in single strand form. (TR50)

  • Membrane (Synthetic)

    A finely porous structure having lateral dimensions much greater than its thickness, through which mass transfer may occur by the application of driving forces like pressure or electro-osmotic. (TR15)

  • Membrane Area

    The effective surface area of a membrane device that is available for filtration. (TR15)

  • Metabolite

    A substance that is either the result of metabolism or a requirement for a metabolic process. (TR70)

  • Method Capability

    The resulting acceptable uncertainty of results to achieve the required capability to detect, quantify, and/or discriminate the analyte at levels that is relevant to the intended use. (TR57)

  • Method Development

    A process that involves the selection, optimization, and qualification of a physical/chemical, biological, molecular, or microbiological test procedure. (TR57)

  • Method Lifecycle

    All stages in the life of a method, from the initial development through marketing, until the method’s discontinuation. (TR57-2)

  • Method Operating Space

    Proven acceptable ranges of a method based on knowledge of the effects of critical instrument and procedural parameters on method performance within the design space. (TR57-2)

  • Method Parameter

    Any factor or method operational step that can be varied continuously (e.g., flow rate) or specified at controllable unique levels (e.g., Gas Chromatograph liner type).

    Source
  • Method Qualification

    Formal or informal study performed to assess initial method performance prior to full ICH Q2 (R1) validation; assessment activity that cul­minates in a scientifically sound method that has an acceptable level of performance and is docu­mented to be suitable for its intended use. (TR56)

    Experimental studies performed to confirm the inherent performance capabilities of a test method for the material being analyzed and the intended use of the method. Method qualification can be performed during early development phases, prior to method validation. Specific method qualification characteristics (e.g., accuracy, specificity) should be confirmed based on the intended use of the analytical method and the relevant risk(s). (TR57)

  • Method Validation

    A formal, archived demonstration of the analyti­cal capacity of an assay that provides justification for use of the assay for an intended purpose. (TR56)

    A formal, archived demonstration of the analytical capacity of an assay that provides justification for use of the assay for an intended purpose. Validations are conducted prospectively according to a written, approved plan that states acceptance criteria. (TR57) (TR57-2)

  • Method, Qualitative

    An analytical procedure, based on the characteristics of a material that yields results that are not amenable to reliable enumeration. (TR57)

  • Method, Quantitative

    An analytical procedure that yields numerical results compared to quantitative specification(s). (TR57)

  • Microbial By-Products

    An analytical procedure that yields numerical results compared to quantitative specification(s). (TR57)

    Organic compounds produced by microorganisms during metabolism and released into the bulk-phase environment. (TR69)

  • Microbial Characterization

    The description of microorganisms based on their cellular morphology, Gram reaction, and key diagnostic tests (e.g., Gram-positive coagulase-negative cocci). (TR13)

  • Microbial Classification

    The arrangement of microorganisms into taxonomic groups based on their similarities and relationships. (TR13)

  • Microbial Count Determination

    A test performed to quantify the number of microorganisms present in a sample of material. Standard microbial methods are utilized to estimate the number of colony forming units (CFU) per unit mass or volume. (TR28)

  • Microbial Enumeration

    Compendial test for microbial counts using the plate-count, membrane-filtration or most probable number methods described in USP <61> Microbiological Examination of Nonsterile Products: Microbial Enumerations Tests. (TR67)

  • Microbial Identification

    The determination of the genus, and species when possible, to which a laboratory or manufacturing isolate belongs. (TR13)

  • Microbiological Examination Tests

    The compendial tests for microbial enumeration and absence of specified microorganisms as found in USP <61> Microbiological Examination of Nonsterile Products: Microbial Enumerations Tests and USP <62> Microbiological Examination of Nonsterile Products: Tests for Specified Microorganisms. (TR67)

  • Microbiological Identification

    Biochemical characterization of isolated colonies to determine the isolate genus and, where feasible and appropriate, the species. (TR22)

  • Micro-condensation

    The formation of very fine layers of condensation often invisible to the naked eye. (TR51)

  • Microdosing Studies

    Studies designed to speed up the development of promising drugs by establishing early on whether the drug or agent behaves in human subjects as was expected from preclinical studies. May in­clude the administration of single subtherapeutic doses of the study drug to a small number of sub­jects (10 to 15) to gather preliminary data on the agent’s pharmacokinetics and pharmacodynam­ics. A Microdosing study gives no data on safety or efficacy, being by definition a dose too low to cause any therapeutic effect. (TR56)

  • Microfiltration (MF)

    Pressure-driven, membrane-based separation process in which particles and dissolved macromolecules (typically 0.1 &;mum or larger) are retained. (TR15)

  • Microorganism

    A microbe; a free-living organism too small to be seen by the naked eye. (TR45) (TR26)

  • Microorganism of Concern

    A bacterium, yeast, or mold that, due to it prominence in product recalls, infection outbreaks, nosocomial infections, and the clinical literature, results in a multifactor risk assessment to determine whether the microorganism is objectionable if it is present in a specific nonsterile product. (TR67)

  • Minimum Acceptable Cycle (MAC)

    The minimum cycle conditions (in terms of delivered minimum lethality or minimum time and temperature) that would be considered acceptable. (TR01) (TR61)

  • Minimum Load

    The minimum quantity or mass of items permitted in a validated depyrogenation or sterilization load. (TR01) (TR3) (TR30) (TR48)

  • Mixed Load

    A load that contains multiple item item types representing various sterilization challenges. For example, some load items may have air removal challenges, while others pose a challenge due to their mass. (TR01)

  • Mock Soil

    A soil which is used in place of the manufactured product during a cleaning validation protocol (also called a “surrogate” soil). (TR29)

  • Mock Soiling

    A process of soiling the equipment for a cleaning validation protocol in which soil is applied to the equipment surfaces to simulate the condition of the soil on those surfaces following typical product manufacturing. (TR29)

  • Module

    An individual unit consisting of multiple membranes in any format within a frame structure containing integral channels and ports for feed, retentate, filtrate and air connections. (TR15)

    Filter element that is incorporated into a cartridge or capsule. (TR26)

  • Moist Heat

    Steam, steam-air mixtures, and superheated water used for sterilization. (TR01)

  • Moist Heat Sterilizer

    Equipment (e.g., a pressure-rated vessel and associated controls) used to achieve sterilization through time, temperature and pressure. [Synonym: Autoclave, Steam Sterilizer] (TR48)

  • Mollicutes

    A class of bacteria which lack a cell wall. Mollicutes are small, typically about 0.1-0.5 &;mum in size, and vary in form (trivial name: mycoplasma) (TR50)

  • Monodispersed particles

    Particles of uniform size in a dispersed phase. In the case of viruses, this term refers to free virus particles not agglomerated to other viruses or proteins in solution. (TR41)

  • Most Probable Number (MPN) Method

    A statistical method of estimating the number of viable organisms suspended in a liquid. (TR51)

  • Multiplicity of Infection (MOI)

    The average number of infectious units added per cell in an infection. (TR41)

  • Mycoplasma

    Small, flexible bacteria that lack a cell wall. Mycoplasma can pass through 0.2 μm and some 0.1 μm rated filters and are unaffected by some antibiotics, such as penicillin. (TR70) (TR47)

  • Mycoplasma Reduction Filter

    A sterilizing grade filter that also provides a log reduction value (or a titer reduction value) for a specified test mycoplasma according to the PDA Mycoplasma Consensus Method. (TR75)

  • Negative Control

    A test article used to assess the performance of an assay in the known absence of a targeted microorganism or nucleic acid. Negative controls are used to minimize a risk of false positive results, which could occur due to non-specific signals. (TR50)

  • New Drug Application (NDA)

    An application filed with the FDA used for the regulation and control of new drugs in the Unit­ed States; the goal is to provide enough infor­mation to permit the FDA reviewer to reach the following key decisions: whether the drug is safe and effective in its proposed use(s), and wheth­er the benefits of the drug outweigh the risks; whether the drugs proposed labeling (package insert) is appropriate, and what it should con­tain; whether the methods used in manufactur­ing the drug, and the controls used to maintain the drug’s quality are adequate to preserve the drug’s identity, strength, quality, and purity. (TR56)

  • Nominal Molecular-Weight Cutoff (NMWCO)

    A manufacturer’s measure of an ultrafiltration membrane based on a defined solute-retention coefficient. (TR15)

  • Nominal Pore Size Rating

    A filter rating with an arbitrary value, indicating a particulate size range at which the filter manufacturer claims the filter removes some percentage. Nominal ratings vary from manufacturer to manufacturer and may not be suitable to compare filters among manufacturers. Processing conditions, such as operating pressure and concentration of contaminant may have a significant effect on the retention efficiency of the nominally rated filters. (TR41)

  • Nominal Value

    The assumed activity of an endotoxin preparation, dilution, or "spike"; based on label-claim information.(TR82)

  • Nonspecific Model Virus

    A virus used for characterization of viral clearance of the process when the purpose is to characterize the capacity of the manufacturing process to remove and/or inactivate viruses in general (i.e., to characterize the general viral clearance capacity of the purification process.) (TR41)

  • Nonviable

    A term used in reference to particulates that are not capable of living, growing, or developing and functioning successfully (“unable to divide” or “not capable of reproducing”). (TR13)

  • Nosocomial Infection (hospital-related infection)

    An infection acquired in a hospital or other healthcare institution that was not present at the time of admission; the most common sites of infection are the urinary tract, surgical wound and lower respiratory tract and bloodstream. The vast majority of nosocomial infections are associated with use of invasive medical devices (e.g., urinary tract catheters, ventilators and central venous catheters). (TR67)

  • Nuclease

    An enzyme capable of cleaving the phosphodiester bonds between the nucleotide subunits of nucleic acids. (TR47)

  • Nucleic Acid Amplification Technique (NAT)

    A method for detection, and in some cases, quantification of target organisms via detection of organism specific nucleic acid. PCR or polymerase chain reaction is a common NAT method that is based on amplification of targeted sequences using primers and specialized DNA polymerases. (TR50)

  • Nucleic Acid Sequence Based Amplification (NASBA)

    An isothermal amplification method targeting RNA in which amplifications of RNA occurs via DNA intermediates. Each of the DNA templates can make 100 to 1000 copies of RNA amplicons, potentially resulting in the production of greater than a billion amplicons. (TR50)

  • Nucleic Acid Standard

    A sample with a precisely measured content of specific nucleic acid. A nucleic acid standard can be serially diluted to assess the limit of detection of an NAT assay or to create a standard curve for Q-PCR to determine the concentration of target nucleic acid. (TR50)

  • Objectionable Microorganism

    According to 21 CFR 211.113 objectionable microorganisms can be: product related or recipient related. Please see glossary for "product related" or "recipient related" for additional information. (TR67)

  • Occult Contamination

    A cell culture contamination not immediately apparent by visual inspection or other obvious indicators. (TR50)

  • Opportunistic Pathogens

    Microorganisms responsible for infection in injured, invasively treated or immune-suppressed individuals that typically do not cause infection in healthy individuals, unlike frank pathogens. (TR67)

  • Optical Density (OD)

    A unitless measure of the absorption of light of a given wavelength in media of a given path length. (TR41)

  • Overkill Design Approach

    A sterilization design approach where minimal information is required about the product bioburden. A worst-case bioburden assumption is used to determine the delivered lethality needed to achieve a PNSU of 10-6 on or in the items being sterilized. When using this approach, the qualification program must demonstrate that both the FBIO and FPHYS are greater than 12 minutes. The required lethality may vary regionally. (Note: For typical SIP systems, the FPHYS will need to be greater than the FBIO.) (TR01) (TR3) (TR30) (TR61)

  • Parametric Release

    A sterility release system based upon effective control, monitoring, documentation, and batch records review of a validated sterilization process cycle in lieu of release procedures based upon end-product sterility testing. (TR01) (TR3) (TR13)

    A sterility release program based on effective control, monitoring and documentation of a validated sterile-product manufacturing process where sterility release is based on demonstrated achievement of critical operational parameters and performance attributes in lieu of end-product sterility testing. (TR30)

  • Partial-Cycle Qualification

    A qualification method that uses less than the full exposure time to demonstrate sterilization or sanitization cycle efficacy. [Synonym: fractional cycle.] (TR61)

  • Passaging

    Propogation of a seed stock by serial sub-culturing. (TR51)

  • Passive Holdover

    The length of time that the temperature remains within the acceptable range when power is lost. (TR64)

  • Pathogen

    Any microorganism which by direct interaction with (i.e., infection of) another organism causes disease in the organism (by convention, a multi-cellular organism). (TR51)

  • Pedigree

    A statement of origin for a drug, active ingredi­ent, or other critical starting material that identi­fies the original source of the material and each sale, purchase, or trade prior to receipt by the user, including the dates, names, and addresses of all parties involved in such transactions. Note: Also called a “batch tree.” (TR56)

  • Penetration Probe

    A probe placed in contact with the load item or inside a container of liquid to measure the temperature of the load item or liquid. (TR01)

    A thermocouple placed in contact with the load item to measure the temperature of the load item. (TR3)

  • Penetration Thermocouple

    A thermocouple that is placed in or against the material/product to measure the material/product temperature. (TR64)

  • Penicylinder

    A small, ceramic carrier surface used to hold cultures of microorganisms. Used in antimicrobial effectiveness testing procedures. (TR70)

  • Pharmacodynamics

    How the drug works in the body, the biochemical and physiological effects of drug and its mecha­nisms of their actions. (TR56)

  • Pharmacokinetics

    How the body processes the drug; the study of the movement of drugs in the body, including the processes of absorption, distribution, localization in tissues, biotransformation, and excretion. (TR56)

  • Phase 1 Clinical Trials

    Phase 1 trials are the first stage of testing in hu­man subjects. Often, a small (20-100) group of healthy volunteers will be selected. For life-threat­ening indications such as oncology, these can be patients that have the target disease but may not yet be the ideal target population. This Phase in­cludes trials designed to assess the safety (phar­macovigilance), tolerability, pharmacokinetics, and pharmacodynamics of a drug. These trials are often conducted in an inpatient clinic, where the subject can be observed by full-time staff. (TR56)

  • Phase 2 Clinical Trials

    Once the initial safety of the study drug has been con­firmed in Phase 1 trials, Phase 2 trials are performed on larger groups (20-300) and are designed to assess efficacy, as well as to continue safety assessments in a larger group of volunteers and patients. Phase 2a is specifically designed to assess dosing requirements (how much drug should be given). Phase 2b trials are specifically designed to study efficacy (how well the drug works at the prescribed dose(s). (TR56)

  • Phase 3 Clinical Trials

    Final clinical stage Phase 3 trials are designed to demonstrate the potential advantages of the new therapy; safety and efficacy of the new therapy are studied over a longer period of time, and more patients (1,000-3,000) are enrolled in the study with less restrictive eligibility criteria. Phase 3 studies are intended to help scientists identify rarer side effects of treatment and prepare for a broader application of the product. Phase 3 trials enroll patients to verify efficacy and monitor ad­verse reactions during long term use. (TR56)

  • Planktonic (Free Floating)

    Suspended in the bulk phase of a fluid as opposed to being attached to surfaces. (TR69)

  • Plaque Forming Unit (PFU)

    A measure of virus infectively based on formation of a region, or “plaque” of lysed cells within a monolayer culture caused by viruses that kill and disrupt their host cell. The number of plaques is directly correlated to the number of infectious virus particles. (TR47)

  • Plaque Purification

    The process of extracting virus from a lawn of plaque for growth in cell culture. By performing several rounds of plaque purification a virus clone can be isolated. (TR47)

  • Plasmid

    An extra-chromosomal DNA molecule in bacteria which is capable of replicating independently of the host chromosomal DNA. Plasmids are often used as positive controls for NAT assays. (TR50)

  • Polymerase Chain Reaction (PCR)

    A technique widely used in molecular biology in which a DNA polymerase is used to amplify a piece of DNA by in vitro enzymatic replication. As PCR progresses, the DNA thus generated is itself used as a template for replication. This sets in motion a chain reaction in which the DNA template is exponentially amplified. This technique may be used to quantify virus. (TR41) (TR47)

  • Porous/Hard Goods Load (P/HG)

    A porous/hard goods load consists of items in which the bioburden is inactivated through direct contact with saturated steam. Porous/ hard goods load items include: filters, stoppers, tubing (hoses), mops, garments, stoppers, cleaning equipment, or machine change parts. (TR01)

  • Positive Control

    A test article used to assess the performance of an assay in the known presence of a targeted microorganism or nucleic acid. A positive control is used to monitor the performance of assay routinely and during validation. For culture-based assays, a live mycoplasma preparation must be used to show that the assay was run properly. NAT positive controls use a nucleic acid with the target sequence of interest. (TR50)

  • Positive Control Filter Membrane (Penetration Control)

    A control filter membrane with a larger pore size rating than the test filter and used to demonstrate the penetrative ability of the test microorganism. Penetration of this filter by at least one CFU is required to validate a test. (TR75)

  • Positive Unit

    Unit filled in an aseptic processing simulation that exhibits detectable microbial growth after incubation. (TR22) (TR62)

  • Precision

    The degree of agreement among individual test results when the procedure is applied repeatedly to multiple samplings of the same suspension of microorganisms and using different suspensions across the range of the test. Also known as repeatability. (TR33)

    The closeness of agreement (degree of scatter) between a series of measurements obtained from multiple sampling of the same homogeneous sample under the prescribed conditions. Precision may be considered at three levels: repeatability, intermediate precision, and reproducibility. It is usually expressed as the variance, standard deviation, or coefficient of variation of a series of measurements. (TR57)

  • Precision, Intermediate

    The closeness of agreement between a series of measurements obtained within laboratory variations (e.g., different days, different analysts, different equipment). (TR57)

  • Precision, Repeatability

    The closeness of agreement between a series of measurements obtained under ideal conditions (e.g., same day, analyst, and instrument). (TR57)

  • Precision, Reproducibility

    The closeness of agreement between a series of measurements for the same sample obtained among different laboratories. (TR57)

  • Preliminary/Process Hazard Analysis (PHA)

    A tool of analysis based on applying prior experience or knowledge of a hazard or failure to identify future hazards, hazardous situations and events that might cause harm, as well as to estimate their probability of occurrence for a given activity, facility, product or system. (TR54-5)
  • Presterilization Bioburden

    Number of viable organisms present on or in product prior to exposure to the sterilization process. (TR30)

  • Primary Contact Surfaces

    All process surfaces that have a direct influence on the quality of the drug substance being manufactured, including surfaces processing equipment, storage containers, and of processing aids during manufacturing operations. (TR54-4)

  • Primer

    A short synthetic single-stranded nucleic acid complementary to a specific sequence of a target gene, DNA or RNA. It usually serves to initiate the de novo synthesis of nucleic acid from a template. (TR50)

  • Probability of a Non-Sterile Unit (PNSU)

    The number that expresses the probability of occurrence of a non-sterile unit after exposure to a sterilization process. Within the pharmaceutical industry, a design end point better than or equal to the probability of one non-sterile unit in a million units is expected, i.e., PNSU ≤ 10–6. [Synonym: Steriliy Assurance Level (SAL)] (TR01)

  • Probability of Detection

    The likelihood of detecting a defective unit dur­ing an inspection process expressed as a prob­ability, quantitatively as a number (0–1) or as a percentage (0–100%). (TR79)

  • Product Changeover

    Procedural steps taken for switching from the manufacturing of one product to another product. (TR29)

  • Product Characterization

    The characterization of quality attributes, such as peptide map, glycosylation, chromatography pro­file, molecular weight, gel chromatogram, poly­morphs, etc. (TR56)


  • Psid

    Pound-force per square-inch differential is the difference in pressure; for example, the pressure differential between the upstream (influent) and downstream (effluent) sides of a filter. (TR75)

  • Psoralen

    A class of UV photoactivated chemicals able to covalently modify nucleic acids. Psoralens may be used to reduce contaminating nucleic acid in NAT reagents. (TR50)

  • Pyrogen

    Any substance capable of eliciting a febrile (or fever) response upon injection or infection (as in endotoxin released in vivo by Gram-negative bacteria. (TR3)

    Fever-producing substance (TR69)

    A material that elicits a pyrogenic response (fever). (TR70)

  • Q-PCR Probe

    A synthetic, chemically-labeled single-stranded nucleic acid complementary to a selected sequence within a DNA sequence to be amplified using forward and reverse primers in a Q-PCR reaction. A probe is typically labeled with both a fluorophor and quencher. The latter inhibits fluorescence until the quencher and fluorophore are separated by the exonuclease activity of DNA polymerase. (TR50)

  • Rapid Microbiological Methods (RMMs; Alternative Microbiological Methods)

    Technologies that allow users to obtain microbiology test results more quickly than traditional microbiological methods, which are usually culture/ growth based. (TR69)

  • Raw Materials

    Starting materials, reagents, and solvents used in the production of intermediates or APIs/drug substance. (TR54-4) (TR83)

  • Recalls

    Actions taken by a firm to remove a product from the marketplace; may be conducted on a firm’s own initiative or in response to an FDA request or order under the agency’s statutory authority. (TR67)

  • Recipient Related

    A microorganism that, due to its numbers and pathogenicity, can cause infection, allergic response or toxemia in patients receiving the product. (TR67)

  • Reference Standard Endotoxin (RSE)

    The primary standard from USP, EDQM, JP and WHO for use in the harmonized compendial bacterial endotoxins test (BET). The current 3rd International Standard (WHO), USP, and EDQM RS are lyophilized formulation that contains highly purified LPS that is chemically extracted and purified from E. coli strain O113:H10:K(-) and further formulated with stabilizers and excipients.(TR82)

  • Reference Strain

    A well characterized, widely accepted preparation of viable organisms that is used to validate a microbiological assay. (TR50)

  • Relevant Virus

    A virus used in process evaluation studies that either is the identified virus, or of the same species as the virus known to or likely to contaminate the cell substrate or any other reagents or materials used in the production process. (TR41)

  • Reporter Gene

    A coding sequence linked to a gene or promoter of interest. It is generally used to determine activation of the promoter or expression of the gene of interest in a cell or organism. (TR50)

  • Retroviruses

    RNA viruses containing a virally-encoded reverse transcriptase enzyme able to transcribe the RNA genome into DNA, which can then be incorporated into the host DNA. (TR47)

  • Reverse Transcriptase PCR (RT-PCR)

    A technique for amplifying a defined segment of a RNA molecule. The RNA is first reverse-transcribed into complementary DNA (cDNA), followed by amplification of the cDNA using PCR. (TR50)

  • Sanitization

    Reduction of microbial contaminants to safe levels as judged by public health requirements for the specific country. (TR13)

    A significant reduction in bioburden, achieved in chromatography by the use of bactericidal agents, such as sodium hydroxide (NaOH), hydrochloric acid (HCl), ethanol (EtOH), and isopropanol (IPA). (TR14)

    The process of reducing microbial levels by treatment at less than defined sterilizing conditions. Typically water at 80 °C or a chemical treatment is used to perform sanitization of process components. (TR45)

    A process that reduces the number of viable microorganisms to a defined level. (TR61) (TR69)

  • Sanitize

    To make physically clean and to remove and destroy, to the maximum degree that is practical, agents injurious to health. (TR70)

  • Sanitizer

    A compound that will reduce the number of vegetative microorganisms to a safe level as determined by public health requirements. Normally a reduction of 103 in vegetative microorganisms is obtained. (TR70)

  • Saturated Steam

    Steam that is at a temperature and pressure that corresponds to the vaporization curve of water. It is in a state of equilibrium between being a liquid and a gas, with no entrained liquid water. [Synonym: Dry Saturated Steam] (TR01) (TR48) (TR61)

  • Saturated Steam Process

    A sterilization process, typically used for porous/hard goods loads, where the sterilizing medium is saturated steam. (TR01)

  • Screening Studies

    Studies used to select a particular type and grade of filter media. (TR45)

  • Sessile Microorganisms

    Microorganisms that are attached to animate or inanimate surfaces, as opposed to planktonic organisms. (TR69)

  • Soil

    The chemical or microbiological materials left on process equipment after completion of process manufacturing, but before initiation of the cleaning process. (TR29)

  • Specified Microorganisms

    Microorganisms with limit tests for absence in 1 or 10 g of a drug product, as described in USP <62> Microbiological Examination of Nonsterile Products: Tests for Specified Microorganisms and USP <1111> Microbiological Quality of Nonsterile Pharmaceutical Products: Acceptance Criteria for Pharmaceutical Preparations and Substances for Pharmaceutical Use. (TR67)

  • Spore

    A bacterial dormant form that is highly resistant to adverse conditions. Fungal spores are not highly resistant; their susceptibilities are closer to vegetative microorganisms. (TR13)

  • Spore Log Reduction (SLR)

    The number of log reductions (10-fold changes) of spores from the initial population. For the overkill sterilization method, one targets a spore log reduction of 12 to achieve 1 x 10-6 probability of a survivor when using a biological indicator having a population of 1 x 106. (TR61)

  • Sporicidal Process

    A process that destroys or inactivates microbial spores. (TR51)

  • Sporicidal Vapor Phase Decontamination

    The destruction of inactivation of microbial spores using a vapor or gaseous agent. (TR51)

  • Sporicide

    A compound that destroys all vegetative microorganisms and bacterial and fungal spores. (TR70)

  • Sporulation

    The formation of a spore. (TR51)

  • Static Monitoring

    Monitoring of the environment in the absence of normal operations. This includes having the equipment installed and operational when no personnel are present. Per the EU and ISO standards, this is synonymous with “at rest.” (TR13)

  • Storage Solution

    A solution typically selected to control bioburden during column storage. (TR14)

  • Strain

    A specific isolate of a species that is maintained in pure culture and is serotypically, genotypically, or chemotaxonomically characterized to differentiate it from other strains of the same species. The strain is representative of the species and provides a reference for the species based on its historic isolation, characterization, and deposition in recognized culture collections. (TR13)

  • Substrate

    Primary construction material of a surface to be cleaned or disinfected. (TR70)

  • Supplemental Testing or Inspection

    Destructive reconstitution, dilution, transfer, clearing, solubilizing, filtration, screening, or sieving that allows a product to be visually exam­ined or evaluated microscopically to determine the presence, type, and size of foreign particulate contamination present within the product, con­tainer, or device. (TR79)

  • Survivor Curve

    Graphical representation of the inactivation of a population of microorganisms with increasing exposure to a microbicidal agent under stated conditions. (TR01) (TR3) (TR51) (TR61)

  • Suspensions

    A suspension is a biphasic preparation consisting of solid particles dispersed throughout a liquid phase. Some suspensions are prepared and ready for use, and others are prepared as solid mixtures intended for reconstitution with an appropriate vehicle just before use. (TR79)

  • Tailing

    Deviation from first-order death kinetics in a microbial population observed when the logarithm of the number of survivors is plotted against time. The “tail” of the survivor curve represents organisms surviving for times in excess of those that would be predicted from first-order kinetics. (TR51)

  • Targeted Species

    The range of species for which detection or analysis is aimed for by an assay method. (TR50)

  • TCld50 Assay

    Quantal assays for determining the titer of a virus. The 50% tissue culture infective does (TCID50) is the dilution of virus that results in the infection of 50% of cell cultures that have been infected with the same dilution of the virus sample. (TR47)

  • Technically Unavoidable Particles (TUPs)

    Particles that are visibly different from the bulk of the material when viewed with the naked eye within the container or against a suitable back­ground (e.g., size, shape, color, number, texture) and are inherent to the manufacturer’s process, product, or raw materials. The unintended pres­ence of a small quantity of particles, stemming from impurities of natural or synthetic ingre­dients, the manufacturing process, storage, or migration from packaging that is technically un­avoidable in good manufacturing practice, and do not pose a risk to patient safety. (TR78)

  • Terminal Sterilization

    A process whereby product is sterilized within its sterile barrier system. (TR01

    The application of a lethal agent to sealed, finished drug products for the purpose of achieving a predetermined sterility assurance level (SAL) of usually less than 10-6 (i.e., a probability of a nonsterile unit of less than one in a million). A process where the material is sterilized in its final packaged configuration. (TR13)

  • Test Sets

    A group of defect standards combined with good or blank units used to evaluate the probability of detection in visual inspection or testing system performance. Test sets can be used for inspec­tor training, validation of automated systems, or other special studies as needed. (TR79)

  • Thermocycling

    Repetition of the PCR reaction steps of denaturing, annealing, and extension. Each step is characterized by different temperatures and reaction times. Some PCR methods combine the annealing and extension steps (i.e., two step PCR). (TR50)

  • Tissue Culture Infectious Dose – TCID50

    The dilution of virus that results in the probability of infection of 50% in replicate tissue-culture inoculations. (TR41)

  • Titer Reduction (TR)

    A measure of the degree to which a particular filter removes a microorganism under specified test conditions. Calculated as the ratio of the total number of microorganisms used to challenge the filter divided by the total number of microorganisms that passed through the filter. (TR75)

  • Toll-like Receptor (TLR)

    A class of single membrane-spanning non-catalytic receptors that recognize structurally conserved molecules derived from microbes. They can activate immune cell responses when microbes have breached physical barriers such as the skin or intestinal tract mucosa. (TR50)

  • Touchdown PCR

    A technique to reduce appearance of non-specific amplicons in PCR reactions. The earliest cycles of a touchdown PCR method have high annealing temperatures. The annealing temperature is decreased in increments for subsequent cycles until a fixed point is reached. (TR50)

  • Turbulent Flow

    Movement of a fluid in which its velocity at any point varies in a random or erratic (nonlaminar) manner. (TR69)

  • Tyndall Lighting

    Collimated lighting at right angle to the viewing direction, typically against a black or dark back­ground, which is useful during manual visual inspection to detect fine dispersions of small par­ticulate that scatter the light making them more detectable. (TR79)

  • Unidirectional Air Flow Hood (UAFH)

    A cabinet designed to protect materials from operator and environmental contamination. Also referred to as laminar air flow hood. (TR62)

  • Unwanted Event or Condition

    Lack of sterility assurance or an unacceptable level of endotoxin that could result in harm to the patient. (TR44)

  • Upstream

    The influent side of the filter. (TR45) (TR26)

  • Vapor Phase Hydrogen Peroxide (VPHP)

    A disinfection system in which 35% hydrogen peroxide is changed to a vapor phase and used for bioburden reduction of a chamber or items in a chamber. (TR70)

  • Vegetative Cell

    Cells in an actively growing state. Some microorganisms can only be vegetative, while others are sporeformers and can be in a vegetative or spore (dormant) state. (TR13)

  • Viable

    Alive and able to be cultured in the laboratory. (TR69)

  • Viable but Nonculturable (VBNC)

    Unable to be cultured in the prevailing test conditions but nonetheless capable of cell division and carrying out metabolic functions (TR69)

  • Virus

    A simple, potentially pathogenic organism composed of a single type of nucleic acid (DNA or RNA) encased in a protein shell (called a capsid) and, in some cases, a lipid membrane (called an envelope). Viruses are incapable of independent replication and therefore must infect a host cell in order to propagate. (TR41)

    Obligate, intercellular, replicating, infectious agents that are potentially pathogenic, possessing only a single type of nucleic acid (either RNA or DNA). They use the host cells for propagation as they are unable to grow independently, for example by binary fission, and multiplying their genomic material. (TR47) (TR83)

  • Virus (Adventitious Virus)

    Unintentionally introduced contaminant viruses. (TR47)

  • Virus (Endogenous Virus

    Viral entity whose genome is part of the germ line of the species of origin of the cell line and can be produced in culture by cell lines from these species. (TR47)

  • Virus (Non-specific Model Virus)

    A virus used for characterization of viral clearance of the process when the purpose is to characterize the capacity of the manufacturing process to remove and/or inactivate viruses in general, i.e., to characterize the robustness of the purification process. (TR47)

  • Virus (Relevant Virus)

    A virus used in process evaluation studies that either is the virus, or of the same species as a virus known to or possible to contaminate the cell substrate or any other reagents or materials used in the production process. (TR47)

  • Virus (Specific Model Virus)

    Virus that is closely related to the known or suspected virus (same genus or family), having similar physical and chemical properties as those of the observed or suspected virus. (TR47)

  • Virus Preparation

    According to the mode of preparation the following terms are used:
    Crude Virus Preparation: A virus preparation that has undergone minimal processing post propagation. The virus is usually separated from cells which are lysed as the result of virus replication or are freezed/thawed in one or several cycles to release the virus from infected cells. The preparation is typically purified from cell debris by low speed centrifugation.
    Purified Virus Preparation: A virus that has undergone purification process by one or more techniques, such as density ultracentrifugation, chromatography or membrane adsorber. The purity of the virus preparation varies depending on the purification technique and should be characterized by appropriate analytical methods. (TR47)

  • Virus Production Lot

    A virus preparation that is used directly in a clearance study. It can be crude or purified. Typically a large volume is produced, tested and qualified. This volume is divided into multiple aliquots for individual clearance studies. (TR47)

  • Virus Removal

    Physical separation of virus particles from the intended product. (TR41)

  • Virus Seed

    An initial virus stock produced after a new virus is introduced into a laboratory. Its purpose is to create a Master Virus Bank. (MVB) (TR47)

  • Visible Particle Range

    Particulate matter sized above the visible particle 70% probability of detection threshold are con­sidered in the visible range, typically >100-150 μm. (TR79)

  • Water Activity (Aw)

    Water Activity, Aw is the ratio of the vapor pressure of water in a product (P) to the vapor pressure of water in a product (P) to the vapor pressure of pure water (Po) at the same temperature. It is numerically equal to 1/100 of the RH generated by the product in a closed system. It is a measure of the free or available moisture in the material. Note: Water activity ≠ water content. RH can be calculated from direct measurements partial vapor pressure or dew point, or from indirect measurements by sensors whose physical or electric characteristics are altered by the RH to which they are exposed. Microorganisms need available water within a pharmaceutical product, as well as nutrients and minerals, to proliferate. Water activity, and not water content, is a better measure of the free water, in contrast to bound water that microbial cells require for metabolic activity and osmotic regulation. Effects of reduced Aw on microbial growth include a longer lag phase, slower growth rate, lower numbers of organisms in the stationary phase, and reduced microbial toxin production; below a specified Aw for an organism, microbial growth will not occur. (TR55) (TR67)

  • Water for Bacterial Endotoxin Test (BET)

    Sterile Water for Injection or other water that shows no reaction with the specific bacterial endotoxin test reagent with which it is to be used, at the limit of sensitivity of such reagent. (TR3)

  • Water for Injection (WFI)

    Water purified by distillation or a purification process that is equivalent or superior to distillation in the removal of chemicals and microorganisms and contains no added substances. (TR45)

  • Zone of Protection/Machine Shroud

    A system fitted to a BFS machine to direct a flow of HEPA-filtered air over the Critical Processing Zone of the machine. (TR77)