Documents that describe the objectives, design, methodology, statistical considerations and aspects related to the organization of clinical trials.

Protocol Amendment

Protocol that have been revised to implement changes such as updating I/E criteria, clarifying points of confusion, and adding or removing required study procedures.

Proven Acceptable Range

A characterized range of a process parameter for which operation within this range, while keeping other parameters constant, will result in producing a material meeting relevant quality criteria.

Proxy Outcome / Proxy Measure

An indirect measure of the desired outcome which is itself strongly correlated to that outcome. It is commonly used when direct measures of the outcome are unobservable and/or unavailable.

Public Notice

A form of notice given to the public regarding certain types of legal proceedings.


The act of cleaning by getting rid of impurities.

Purified Water

Water that has been mechanically filtered or processed to remove impurities.


An increase in the number of cells as a result of cell growth and cell division. Cell proliferation occurs by a process known as cell division.


Treatment or actions taken to prevent a disease.

Prospective Validation

The validation of a manufacturing process before commercial production begins or a new process is implemented.

Plasmid DNA

A small, extrachromosomal DNA molecule within a cell that is physically separated from chromosomal DNA and can replicate independently.

Plaque Assay

Plaque-based assays are a commonly used method to determine virus concentration in terms of infectious dose. Plaque assays determine the number of plaque forming units (PFU) in a virus sample, which is one measure of virus quantity.


A condition in a recipient that might increase their risk for a serious adverse reaction, might cause diagnostic confusion, or might compromise the vaccine’s ability to produce immunity.

Plaque forming unit (PFU)

Measure used to describe the number of virus particles capable of forming plaques per unit volume. Viral particles that are defective or which fail to infect their target cell will not produce a plaque and thus will not be counted.

Post Market Surveillance

Practice of monitoring the safety of a pharmaceutical drug or medical device after it has been released on the market, thereby further refine, or confirm or deny, the safety of a drug or device after it is used in the general population by large numbers of people who have a wide variety of medical conditions.

Primary antibody

An antibody that can bind to a specific protein or a biomolecule of interest.

Pneumococcal conjugate vaccine

A pneumococcal vaccine made with the conjugate vaccine method and used to protect infants, young children, and adults against disease caused by the bacterium Streptococcus pneumoniae (pneumococcus).

Post Market Surveillance (PMS)

The practice of monitoring the safety of a pharmaceutical drug or medical device after it has been released on the market.

Primary immunodeficiency disorder

A heterogeneous group of rare, inherited disorders characterized by poor or absent function in one or more components of the immune system.


Inflammation of the lungs characterized by fever, chills, muscle stiffness, chest pain, cough, shortness of breath, rapid heart rate, and difficulty breathing.


A measure of activity expressed in terms of the amount required to produce an effect of given intensity.

Primary objective

the main goal or purpose that guides someone’s actions or decision-making process.

Point mutation

A genetic mutation where a single nucleotide base is changed, inserted or deleted from a DNA or RNA sequence of an organism’s genome.

Power (Statistics)

The probability of rejecting the null hypothesis when, in fact, it is false.

Primary structure

The characteristic sequence of amino acids forming a protein or polypeptide chain, considered as the most basic element of its structure.


An acute infectious viral disease caused by poliovirus, characterized by fever, paralysis, and atrophy of skeletal muscles. Also known as polio.

Pragmatic Trial (or Study)

Clinical trial that focuses on correlation between treatments and outcomes in real-world health system practice rather than focusing on proving causative explanations for outcomes.

Principal Investigator

The individual who assumes full responsibility for the research project including supervision of co-investigators, key personnel, and the Institutional Review Board (IRB) submission process.


An acute infectious viral disease characterized by fever, paralysis, and atrophy of skeletal muscles. Also known as polio.


How close two or more measurements are to each other.

Principal Investigator (PI)

The holder of an independent grant and the lead researcher for the grant project, usually in the sciences, such as a laboratory study or a clinical trial.

Poly A-tail

A long chain of adenine nucleotides that is added to a mRNA molecule during RNA processing. In eukaryotes, polyadenylation is part of the process that produces mature mRNA for translation. In many bacteria, the poly(A) tail promotes degradation of the mRNA.


Relating to or denoting the stage of drug testing that precedes the clinical stage.

Principle of autonomy

The ability of competent subjects to make their own decisions be recognized and respected, and protection of the vulnerable from imposition of unwanted decisions.


Pertaining to cells or cell products derived from several lines of clones.

Preferred Terms

The term traditionally used to report the frequency of adverse events.

Process Analytical Technologies (PAT)

A term defined by the United States Food and Drug Administration (FDA) as a mechanism to design, analyze, and control pharmaceutical manufacturing processes through the measurement of critical process parameters (CPP) which affect the critical quality attributes (CQA).


A measure of the heterogeneity of sizes of non-uniform molecules or particles in a mixture.


A written direction for the preparation and administration of a remedy.


Any of several enzymes that catalyze the formation of a long-chain molecule by linking smaller molecular units, as nucleotides with nucleic acids.


The ratio of cases of a condition or diseases within a population.


The presence of two or more variant forms of a specific DNA sequence that can occur among different individuals or populations.

Process Validation

Documented evidence demonstrating the effective and reproducible production of pharmaceuticals that comply with pre-established specifications and quality characteristics when operating within predetermined ranges.


A lysosomal storage disorder characterized by the excess accumulation of phospholipids in tissues.

Phase III trial

Phase III trial is designed to assess the effectiveness of the new intervention and, thereby, its value in clinical practice. It is randomized controlled multicenter trials on large patient groups (300–3,000 or more) and is aimed at being the definitive assessment of how effective the drug is, in comparison with current gold standard treatment.

Polysaccharide vaccine

Vaccine produced from the polysaccharide (sugar) coating of an encapsulated bacterium.


An early symptom indicating the onset of an attack or a disease.


Resistant to change under the influence of radiant energy and especially of light.

Phase Ⅳ trial / Post Marketing Surveillance

Phase IV trial is designed to detect any rare or long-term adverse effects over a much larger patient population and longer time period than was possible during the Phase I-III clinical trials.


Long-chain polymeric carbohydrates composed of monosaccharide units bound together by glycosidic linkages.

Product Liability (PL)

The area of law in which manufacturers, distributors, suppliers, retailers, and others who make products available to the public are held responsible for the injuries those products cause.


A substance or treatment that has no effect on living beings, usually used as a comparison to vaccine or medicine in clinical trials.


The observable characteristics or traits in an individual organism based on the expression of their genes.

Pooled analysis

A statistical technique for combining the results of multiple studies.

Product Life Cycle

The length of time from a product first being introduced to consumers until it is removed from the market.


A plasmid is a small, circular, double-stranded DNA molecule that is distinct from a cell’s chromosomal DNA. Plasmids naturally exist in bacterial cells, and they also occur in some eukaryotes. Often, the genes carried in plasmids provide bacteria with genetic advantages, such as antibiotic resistance. Scientists have taken advantage of plasmids to use them as tools to clone, transfer, and manipulate genes. Plasmids that are used experimentally for these purposes are called vectors. Researchers can insert DNA fragments or genes into a plasmid vector, creating a so-called recombinant plasmid. This plasmid can be introduced into a bacterium by way of the process called transformation.


An infectious disease caused by the bacterium Yersinia pestis. There are three forms of plague, each affecting a different part of the body and causing associated symptoms. Pneumonic plague infects the lungs, causing shortness of breath, coughing and chest pain; bubonic plague affects the lymph nodes, making them swell; and septicemic plague infects the blood and can cause tissues to turn black and die.


The entire population to which the intervention of a clinical trial or research study is applied.


All operations involved in the preparation of a pharmaceutical product, from receipt of materials, through processing, packaging and repackaging, labelling and relabelling, to completion of the finished product.


A small, well-defined bump in the skin.


A tiny reddish or purplish spot on the skin or mucous membrane, commonly part of infectious diseases such as typhoid fever.

Parallel Design

A type of study design in which participants are randomly assigned to treatment arms and then remain in that same treatment arm throughout the course of the study.


Substance used in the diagnosis, treatment, or prevention of disease and for restoring, correcting, or modifying organic functions.


A variable whose measure is indicative of a quantity or function that cannot itself be precisely determined by direct methods.

Pharmaceutical Inspection Cooperation Scheme

A non-binding, informal co-operative arrangement between Regulatory Authorities in the field of Good Manufacturing Practice (GMP) of medicinal products for human or veterinary use.

Partial immunity

Some degree of protection from a disease. The host with partial immunity can be infected again, but with a lower probability.

Pharmaceutical product

Any material or product intended for human or veterinary use presented in its finished dosage form, or as a starting material for use in such a dosage form, that is subject to control by pharmaceutical legislation in the exporting state and the importing state.

Particle Size

A notion introduced for comparing dimensions of solid particles (flecks), liquid particles (droplets), or gaseous particles (bubbles).

Pharmaceutical Quality System

A set of procedures and practices that ensures medicinal products fit for their intended use, comply with relevant authorisation requirements, and do not place patients at risk due to inadequate safety, quality or efficacy.

Partition Coefficient

The ratio of the concentrations of a solute in two immiscible or slightly miscible liquids, or in two solids, when it is in equilibrium across the interface between them.


A health-care professional licensed to engage in pharmacy with duties including dispensing prescription drugs, monitoring drug interactions, administering vaccines, and counseling patients regarding the effects and proper usage of drugs and dietary supplements.


Bacterial infectious disease caused by Bordetella pertussis, marked by a convulsive spasmodic cough, sometimes followed by a crowing intake of breath. Also known as whooping cough.

Passive immunity

Protection against disease through antibodies produced by another human being or animal. Passive immunity is effective, but protection is generally limited and diminishes over time (usually a few weeks or months). For example, maternal antibodies are passed to the infant prior to birth and protect the baby for the first 4–6 months of life.


An insect or small animal that is harmful.


Organisms (such as bacteria, viruses, parasites and fungi) that cause disease in human beings.


Quantitative measure of the acidity or basicity of aqueous or other liquid solutions.


The process by which a disease or disorder develops.


The study of how genes affect a person’s response to drugs. Combines pharmacology and genomics to develop effective, safe medications that can be prescribed based on a person’s genetic makeup.


The specialty of medical science concerned with the cause, development, structural/functional changes, and natural history associated with diseases.

Pharmacokinetics (PK)

A branch of pharmacology dedicated to describing how the body affects a specific substance after administration. A number of phases occur once the drug enters into contact with the organism, these are described using the acronym ADME (Absorption, Distribution, Metabolism, Excretion).

Phase I trial

Phase I study is the first stage of testing drugs in human subjects. They are designed to test the safety, side effects, best dose, and formulation method for the drug. Phase I trials are not randomized, and the drug is given to small group of 20-100 healthy volunteers.


Of or relating to the medical care or illnesses of children.


Process and science of monitoring the safety of medicines and taking action to reduce the risks and increase the benefits of medicines.

Phase II trial

Phase II trials are clinical trial performed on larger groups (50–300 individuals) and are designed to assess effect and biologic activity of drug, as well as to continue Phase I safety assessments in a larger group of volunteers and patients.


An antibiotic drug obtained from molds of the genus Penicillium and used to treat or prevent various infections caused by gram-positive bacteria such as streptococcus.

Pharmacy Law

A comprehensive set of statutes, rules, and guidelines overseeing pharmacy practice, medication distribution, and other products.

Per Protocol Set

A set of patients who followed the rules of the study and completed the study without major protocol deviations.


All operations, including filling and labelling, that a bulk product has to undergo in order to become a finished product. Filling of a sterile product under aseptic conditions or a product intended to be terminally sterilized, would not normally be regarded as part of packaging.

Per-Protocol Analysis

Inclusion in the analysis of only those patients who strictly adhered to the protocol.

Packaging material

Any material, including printed material, employed in the packaging of a pharmaceutical, but excluding any outer packaging used for transportation or shipment. Packaging materials are referred to as primary or secondary according to whether or not they are intended to be in direct contact with the product.

Performance Qualification(PQ)

Documented verification that ensures that all equipment and systems function properly and do not compromise product quality.


A widespread occurrence of an infectious disease over a whole country or the world at a particular time such as AIDS, pH1N1, or SARS-CoV-2.


The ability of a substance to allow gases or liquids to go through it.