Submission Unit

A collection of documents pertaining to a particular clinical study protocol and/or medical product accompanied by the associated reference information officially provided to the regulatory authority. This is usually done to comply with a specific regulatory purpose or decision.


The reactant which is consumed during a catalytic or enzymatic reaction.

Subunit vaccine

A vaccine that contains purified parts of the pathogen that are antigenic, or necessary to elicit a protective immune response.

Sudden Infant Death Syndrome (SIDS)

The sudden and unexpected death of a healthy infant younger than 1 year of age. A diagnosis of SIDS is made when an autopsy cannot determine another cause of death. The cause of SIDS is unknown. Also known as crib death or cot death.

Sulfotransferase (SULT)

A family of phase II enzymes transferring a sulfate group from 3′-phosphoadenylyl sulfate to the hydroxyl group of an acceptor. It plays important role in metabolism of various drugs.

Superiority Trial

A trial aims to show that one treatment is clinically better than the other by demonstrating superiority of the test agent over placebo.


To take the place of and serve as a substitute for especially by reason of superior excellence or power.


A metabolically active assembly of phospholipids and surfactant-specific proteins that is essential for normal lung mechanic.

Surrogate Marker

A laboratory measurement or physical sign that is used in therapeutic trials as a substitute for a clinically meaningful endpoint that is a direct measure of how a patient feels, functions, or survives and is expected to predict the effect of the therapy.

Synergistic Effect

The situation when the interaction between two or more drugs causes the total effect of the drugs to be greater than the sum of the individual effects of each drug.

Structural Verification

The actions performed to document and prove that software is structurally appropriate and free of defects.

Surrogate Variable

A variable that can be measured (or is easy to measure) that is used in place of one that cannot be measured (or is difficult to measure).


A disease that is caused by the bacterium Treponema pallidum and spread through sexual intercourse. The primary stage classically presents with a single painless skin ulceration. In secondary syphilis, a diffuse rash occurs, which frequently involves the palms of the hands and soles of the feet. In tertiary syphilis, there are gummas, neurological problems, or heart symptoms.


The ongoing evaluation of an individual who has an increased risk of developing a disease or who has a disease that appears to be clinically stable or not progressing.

Subclinical infection

The presence of infection without symptoms. Also known as inapparent or asymptomatic infection.


A mixture in which particles are dispersed throughout the bulk of a fluid.


Any individual member of the clinical trial team designated and supervised by the investigator at a trial site to perform critical trial-related procedures and/or to make important trial-related decisions (e.g., associates, residents, research fellows).

Systematic Review

Study that involves thorough examination of all literature on a specific topic, applying explicit selection and exclusion criteria to choose relevant literature, conducting quality assessments of the selected literature, and synthesizing research findings.


A person who participates in a clinical trial and is subject to the application of investigational drugs, medical devices, or control devices.

Systemic Circulation

The circuit of vessels supplying oxygenated blood to and returning deoxygenated blood from the tissues of the body, as distinguished from the pulmonary circulation.

Subject Identification Code

A unique identification code assigned by the principal investigator to each subject to protect their identity. This code is used by the principal investigator to report adverse events or other clinical trial-related data instead of the subject’s name.

Systemic lupus erythematosus

A disease characterized by inflammation of the connective tissue that supports and connects all parts of the body. Chronic swelling of the connective tissue causes damage to the skin, joints, kidneys, nervous system, and mucous membranes. The disease begins with fever, joint pain, and fatigue. Additional symptoms continue to develop over the years, including nausea, fatigue, weight loss, arthritis, headaches, and epilepsy. Problems with heart, lung, and kidney function may also result. This condition is diagnosed most frequently in young women but occurs in children as well.


Development of antibodies in the blood of an individual who previously did not have detectable antibodies.

Solution Stability

The property of a drug that does not undergo decomposition or reaction within a solution.

Statistical process control

The application of statistical methods to the monitoring and control of a manufacturing process to ensure that it operates at its full potential to produce a conforming product.


Measurement of antibodies and other immunological properties present in blood serum.


Any substance, usually liquid, which is capable of dissolving one or several substances, used for the preparation of solutions or suspensions during the manufacture of intermediates or APIs.

Stem cell

Undifferentiated or partially differentiated cells that can change into various types of cells and proliferate indefinitely to produce more of the same stem cell.


The level of a pathogen in a population, as measured in blood serum.

Source Data

All information in original records and certified copies of original records of clinical findings, observations, or other activities in a clinical trial necessary for the reconstruction and evaluation of the trial.


The process of making something free from bacteria or other living microorganisms.


A study measuring the proportion of persons in a community that have antibodies (due to vaccination or previous exposure) to a given agent.


Condition of being free from living germs or microorganisms.


A way of grouping cells or microorganisms, such as bacteria or viruses, based on the antigens or other molecules found on their surfaces.

Source Document

Original documents, data and records of the subject before, during and after the trial that allows independent observer to reconfirm the data and reconstruct the trial as it happened.

Sterility assurance level

The probability that a single unit that has been subjected to sterilization nevertheless remains nonsterile.


Probability of a negative test result, conditioned on the individual truly being negative.


The fluid and solvent component of blood. Serum contains all proteins except clotting factors (involved in blood clotting), including all electrolytes, antibodies, antigens, hormones; and any exogenous substances (e.g., drugs, microorganisms).


A list of detailed requirements with which the products or materials used or obtained during manufacture have to conform. They serve as a basis for quality evaluation.

Standard Operating Procedure (SOP)

Treatment that is accepted by medical experts as a proper treatment for a certain type of disease and that is widely used by healthcare professionals.

Severe Combined immune Deficiency (SCID)

A group of rare, life-threatening disorders caused by at least 15 different single gene defects that result in profound deficiencies in T- and B- lymphocyte function.


Study of the absorption and emission of light and other radiation by matter, as related to the dependence of these processes on the wavelength of the radiation.


A device for mixing liquids or flowable solids contained in a container.


A form of isomerism in which molecules have the same molecular formula and sequence of bonded atoms (constitution), but differ in the three-dimensional orientations of their atoms in space.


Limit on the period of storage time during which the pharmaceutical or drug product is considered fit for use and effective.

Spike protein

A protein that forms a large structure known as a spike or peplomer projecting from the surface of an enveloped virus.  The proteins are usually glycoproteins that form dimers or trimers. Spikes typically have a role in viral entry. They may interact with cell-surface receptors located on the host cell and may have hemagglutinating activity as a result, or in other cases they may be enzymes.


A specific version of an organism. Many agents causing diseases, including HIV/AIDS and hepatitis, have multiple strains.


Act of sorting data, people, and objects into distinct groups or layers.


An infection of the intestines caused by Shigella bacteria. Symptoms generally start one to two days after exposure and include diarrhea, fever, abdominal pain, and feeling the need to pass stools even when the bowels are empty. The diarrhea may be bloody.


A person, company, institution, group, or organization that oversees or pays for a clinical trial and collects and analyzes the data.

Streptococcus pneumoniae

A Gram-positive, spherical bacteria, alpha-hemolytic member of the genus Streptococcus. They are usually found in pairs (diplococci) and do not form spores and are non motile. It is a major cause of pneumonia, and recognized as a significant human pathogenic bacterium.


A disease characterized by painful skin lesions that occur mainly on the trunk (back and stomach) of the body but can also develop on the face and in the mouth. Complications include headache, vomiting, fever, and meningitis. Recovery can take up to 5 weeks. Herpes Zoster is caused by the same virus responsible for chickenpox. Most people are exposed to this virus during childhood. After the primary infection (chickenpox), the virus becomes dormant, or inactivated. In some people the virus reactivates years, or even decades, later and causes herpes zoster. Also known as the herpes zoster.


A substance, such as a disinfectant or other chemical, that kills spores.

Side Effect

Refers to all unintended effects that occur when a drug is administered at normal dosages, including adverse experiences (AE), signals, and adverse drug reactions (ADR).

Stability Test

A method to check the quality and how the system or software behaves in different environmental parameters like temperature, voltage etc.


Probability of a positive test result, conditioned on the individual truly being positive.

Significance level

The probability of the study rejecting the null hypothesis, given that the null hypothesis is true.


A point in a project or plan at which development can be examined and any important changes or decisions relating to costs, resources, profits, etc.

Sensitivity Analysis

Determination of how different values of an independent variable affect a particular dependent variable under a given set of assumptions. In meta-analysis, sensitivity analysis means testing the robustness of the results by analyzing how the inclusion or exclusion of a specific primary study in the meta-analysis changes the overall results, thereby assessing the impact of that particular study on the meta-analysis outcome.

Silence (Gene)

Mutations in DNA that do not have an observable effect on the organism’s phenotype. Mutations that cause the altered codon to produce an amino acid with similar functionality (e.g. a mutation producing leucine instead of isoleucine) are often classified as silent.


A person, group or organization with a vested interest, or stake, in the decision-making and activities of a business, organization or project.


Areas that are separated by walls, where access of personnel or air conditioning units is segregated.

Small biologic

Small-sized biologics, such as antibodies that are typically composed of 2,000 to 3,000 atoms.

Standard treatment

Treatment that is accepted by medical experts as a proper treatment for a certain type of disease and that is widely used by healthcare professionals. In many scientific studies, the control group receives the standard treatment rather than a placebo while a treatment group receives the experimental treatment.


A condition which is the consequence of a previous disease or injury.

Small Interfering RNA (siRNA)

A class of double-stranded RNA at first non-coding RNA molecules, typically 20–24 (normally 21) base pairs in length, similar to miRNA, and operating within the RNA interference (RNAi) pathway.

Starting material

Any substance of a defined quality used in the production of a pharmaceutical product, but excluding packaging materials.

Serious Adverse Event (SAE)

Adverse event associated with use of medical product, which includes death, life threatening, hospitaliation, disability and/or permanent damage, congenital anomaly and/or birth defect.


An acute, highly infectious, often fatal disease caused by a poxvirus and characterized by high fever and aches with subsequent widespread eruption of pimples that blister, produce pus, and form pockmarks. Also known as variola.

Statistical inference

The process of using sample statistics to answer questions about population parameters.

Sealed vessel

A container that prevents intrusion of gases or microbes under normal handling or storage conditions.

Secondary antibody

Antibody that binds to primary antibodies and provide signal detection and amplification along with extending the utility of an antibody through conjugation to proteins. Secondary antibodies are especially efficient in immunolabeling.

Secondary endpoint

Endpoint that may provide supportive information about a therapy’s effect on the primary endpoint or demonstrate additional effects on the disease or condition.

Secondary standards

Reference material with a potency calculated relative to a primary standard and can be used as calibrant and/or positive control and/or monitor in an assay.

Secondary structure

Local spatial conformation of the polypeptide backbone excluding the side chains. It is formally defined by the pattern of hydrogen bonds between the amino hydrogen and carboxyl oxygen atoms in the peptide backbone. The two most common secondary structural elements are alpha helices and beta sheets.

Seed Lot System

A system in which successive batches of a product are derived from the same master seed lot at a given passage level to prevent the unwanted drift of properties that might ensure from repeated subcultures or multiple generations.


The sudden onset of a jerking (localized or generalized) or staring spell. Seizures following a vaccination can be caused by fever. Also known as convulsions.

Selection Bias

Type of bias introduced by the selection of individuals, groups, or data for analysis in such a way that proper randomization is not achieved, thereby failing to ensure that the sample obtained is representative of the population intended to be analyzed.

Self-amplifying mRNA

A type of mRNA that encodes a replicase that copies the original strand of RNA once it enters the cell.

Self-contained area

Premises which provide complete and total separation of all aspects of an operation, including personnel and equipment movement, with well established procedures, controls and monitoring. This includes physical barriers as well as separate air-handling systems, but does not necessarily imply two distinct and separate buildings.


(Chemistry) A chemical compound consisting of an ionic assembly of positively charged cations and negatively charged anions.

Sample size

The number of participants or observations included in a study.


Of or relating to good health or protection from dirt, infection, disease, etc.


The causal agent of Coronavirus Disease 2019 (COVID-19).


Used to describe a system that can be made larger, without affecting its performance.