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Data Subsets
US Approved Drugs
A list of drugs that have been approved by the FDA for marketing in the US according to one or more of the following sources:
  • DailyMed
  • Drugs@FDA
  • OrangeBook
  • Code of Federal Regulations Title 21 – Over-the-Counter Drugs
Marketed Drugs
Substances that have a record of ever having been approved for marketing anywhere in the world according to any of the sources used in NCATS Inxight.
Investigational Drugs
Substances that have ever entered any clinical trial regardless of the outcome, but have not been approved or marketed.
All Substances
All substances in the database.

Drug (therapeutic, intervention)

The "platonic", idealized form of an active pharmaceutical ingredient included in or produced by a currently or previously marketed drug product to contribute to the pharmacological action used to treat a condition. Usually an active moiety, except for prodrugs.

Active Pharmaceutical Ingredient

A substance present in a currently or previously marketed drug product that is or becomes pharmacologically active once delivered to patients.


A substance that is not pharmacologically active until covalently modified by endogenous biological activity.

Active Moiety

The essential aspect of a substance responsible for its pharmacological activity.

21 CFR 314.108(a):

The molecule or ion, excluding those appended portions of the molecule that cause the drug to be an ester, salt (including a salt with hydrogen or coordination bonds), or other noncovalent derivative (such as a complex, chelate, or clathrate) of the molecule, responsible for the physiological or pharmacological action of the drug substance.

Drug Product

A regulated, packaged, and formulated product currently or previously marketed for medical use containing one or more active pharmaceutical ingredients.


Fundamentally, an ingredient in a drug product. Substances are catalogued by the Federal Drug Administration (FDA) and assigned a UNique Ingredient Identifier (UNII). Multiple substances can share the same active moiety. Currently, there are six distinct types of Substances, as defined by the ISO 11238 identification of medical products standard: chemical, protein, nucleic acid, polymer, structurally diverse, and mixture. In addition, FDA defines a "concept" as a collection of names, codes, and relationships, which refer to matter that does not fit the definition of a substance, but is still of research, regulatory, or clinical significance. To ensure comprehensive coverage and avoid ambiguity, NCATS Inxight: Drugs includes concepts into its list of Substances.

ISO 11238:

Any matter that has discrete existence, whose origin may be biological, mineral or chemical. Substances can be either single substances or mixture substances. Single substances shall be defined using a minimally sufficient set of data elements divided into five types, chemical, protein, nucleic acid, polymer, and structurally diverse. Substances may be salts, solvates, free acids, free bases, mixtures of related compounds that are either isolated or synthesized together.

Primary Target

A biological component, substance, or process that is modulated by a therapeutic intervention, and is suspected to be the most relevant target for the biological activity associated with the major pharmacological use or proposed indication of the therapeutic intervention.

Treatment Modality

Substances are classified based on their effect on disease progression for a specific disease or condition.
NCATS Inxight uses the following categories:
Halts or slows disease progression. Treatment often targets the primary pathology of a disease.
Intended to prevent the development of a medical condition.
Improves the quality of life by alleviating the associated symptoms, without necessarily affecting the underlying pathology.
Treats adverse effects associated with the treatment of a condition.
A substance used for diagnostic purposes, including disease detection and monitoring of disease progression.
Inactive ingredient
An ingredient of a given formulation (most frequently, an excipient) that does not exhibit pharmacological activity. In this case, a condition is only related to such compound via the formulation used to affect (treat or diagnose) this condition.