Naïve polysaccharide

The polysaccharide that comprises the cell that is in its native or natural state and unaltered by denaturing agent, such as heat, chemical, enzyme action, or the exigencies of extraction.

Naïve protein

The protein inside the cell that is in its native or natural state and unaltered by denaturing agent, such as heat, chemical, enzyme action, or the exigencies of extraction.


The reduction in viral infectivity by binding the antibody to the surface of viral particles (virion), blocking the viral replication cycle.


A type of white blood cell. It is the most abundant type of granulocytes and make up 40% to 70% of all white blood cells in humans. that plays an important role in acute inflammation. It migrates toward sites of infection or inflammation, through process called ‘chemotaxis’, and activate other immune cells by releasing cytokines. It is also capable of phagocytosis and degranulation of antimicrobial granules, playing key role as a part of innate immunity.

New Biological Entity (NBE)

A biologic compound or vaccine not previously approved for human use by the Center for Biologics Evaluation and Research (CBER).

New Chemical Entity (NCE)

A chemically synthesized pharmaceutical that does not possess any active derivatives approved by the US FDA.

National Regulatory Agencies (NRA)

Agencies responsible for ensuring that products released for public distribution (normally pharmaceuticals and biological products, such as vaccines and medical devices including test kits) are evaluated properly and meet international standards of quality and safety and efficacy. 

New Drug Application (NDA)

A type of application in which a pharmaceutical manufacturer or its agent requests permission from the Food and Drug Administration (FDA) for a license to market or sale a drug for one or more specified indications.


The examination of the body of an animal after its death.

Newcastle Disease Virus (NDV)

A virus that causes Newcastle Disease, a viral avian disease affecting many domestic and wild bird species. Though it can infect humans, most cases are non-symptomatic and rarely it can cause a mild fever and influenza-like symptoms and/or conjunctivitis in humans. Strains of Newcastle disease virus have been used to create viral vector vaccine candidates against Ebola and Covid-19.

Nonclinical Study

In vivo or in vitro experiments in which test articles are studied prospectively in test systems under laboratory conditions to determine their safety.

Normal operating range

A range that describes a region around the target operating conditions that contain common operational variability.

Neutralization test

Test that measures the ability of the patient’s antibody to neutralize infectivity and protect cells from infection.

Nuclear Magnetic Resonance (NMR)

A physical phenomenon in which nuclei in a strong constant magnetic field are perturbed by a weak oscillating magnetic field (in the near field) and respond by producing an electromagnetic signal with a frequency characteristic of the magnetic field at the nucleus.

New Molecular Entity (NME)

A drug whose active ingredient contains no active moiety that has been previously approved by the FDA.


Glycosylamines that can be thought of as nucleotides without a phosphate group. A nucleoside consists simply of a nucleobase and a five-carbon sugar.

Nucleoside Triphosphate (NTP)

A nucleoside containing a nitrogenous base bound to a 5-carbon sugar (either ribose or deoxyribose), with three phosphate groups bound to the sugar. They are the molecular precursors of both DNA and RNA, which are chains of nucleotides made through the processes of DNA replication and transcription.

Non-Inferiority Trial

A study that tests whether a new treatment is not worse than an active treatment it is being compared to.

Nuisance parameter

A parameter that must be estimated, even though it is of no immediate interest. The most familiar example occurs in the construction of a confidence interval for an estimate of a population mean. The sample mean is the obvious estimate, but the population variance is a nuisance parameter that must also be estimated in order to determine the size of the interval.

Null Hypothesis

A type of statistical hypothesis that proposes that no statistical significance exists in a set of given observations.

Nuremberg Code

A set of ethical research principles for human experimentation created by the court in U.S. v Brandt, one of the Subsequent Nuremberg trials that were held after the Second World War.