Active pharmaceutical ingredient (API) meaning

In legal and regulatory practice, an active pharmaceutical ingredient (API)—also called the drug substance—is the component of a finished medicinal product that provides the pharmacological or other direct effect (for diagnosis, cure, mitigation, treatment or prevention of disease, or to affect body structure or function). UK and Irish medicines legislation uses the term “active substance” and defines it consistently with EU law (Directive 2001/83/EC), implemented in the UK by the Human Medicines Regulations 2012 and in Ireland by national regulations. “API” is the synonymous industry term used in guidance such as ICH Q7. The term is descriptive and not typically defined by case law. APIs must be manufactured under GMP in appropriately authorised or registered facilities. Manufacturers, importers and distributors are subject to oversight by the MHRA (UK) and HPRA (Ireland), with EU/EEA coordination via the EMA. The API itself is not separately registered as a product in the UK or Ireland; instead, detailed API data are filed in the marketing authorisation dossier (commonly via an ASMF or EDQM CEP; a US-facing supply chain references an FDA DMF). Medicinal products also contain excipients (non-active components). Intermediates formed during synthesis are not APIs until meeting the defined identity, quality and potency. Usage is...