The vocabulary that decides what a claim means

The basic building block of peptides and proteins. Twenty standard amino acids combine in sequence to determine a molecule's shape and activity.

The chemical link joining two amino acids. A chain of these bonds forms a peptide; enzymes called peptidases break them.

A molecule that binds a receptor and activates it, producing a biological response similar to the natural signal.

A molecule that binds a receptor without activating it, blocking the natural signal from producing its effect.

The proportion of an administered dose that reaches systemic circulation in active form. Most peptides have very low oral bioavailability.

What the body does to a substance: absorption, distribution, metabolism, and elimination. Often summarised as exposure over time.

What a substance does to the body: the relationship between exposure and biological effect, including receptor activity.

How a substance enters the body — subcutaneous, intramuscular, oral, topical, intranasal. Route strongly affects exposure and risk.

The tendency of a substance to provoke an immune response, including anti-drug antibodies that can reduce effect or cause reactions.

Under clinical study without marketing authorisation. Investigational status describes a stage of evaluation, not a level of safety.

Research conducted before human testing, typically in cells and animal models. Preclinical findings often fail to replicate in people.

A prospective study in humans conducted under a protocol with defined endpoints, eligibility criteria, and ethics oversight.

Randomised controlled trial. Participants are assigned to intervention or comparator by chance, which limits bias and confounding.

A structured synthesis of all studies meeting prespecified criteria, designed to reduce selective use of evidence.

Statistical pooling of results from multiple studies. Pooling low-quality studies produces a precise-looking but unreliable estimate.

Performed outside a living organism, typically in cell culture. Useful for mechanism, weak evidence for clinical effect.

Performed in a living organism. In animal models, in vivo results still require human confirmation.

Preparation of a medicine by a pharmacy or outsourcing facility for a specific clinical need. Compounded products are not premarket-reviewed for safety and efficacy.

A commercial label indicating the seller is not marketing the material as a medicine. It is not a quality standard and does not indicate suitability for human use.

A measurable substitute for a clinical outcome, such as a biomarker. Surrogates can improve while patient outcomes do not.