Drug master file (revision 15)

A drug master file (DMF) is a submission to a medicines regulator containing confidential detail about the manufacture, processing and control of a substance. Its purpose is to allow a customer's application to reference that detail without the holder disclosing it to the customer.^[1]

A DMF is not an approval. Filing one causes it to be assigned a number and acknowledged; the regulator reviews its content only when an application referencing it is reviewed, and a review finding may be adverse.^[1]

Equivalent mechanisms exist elsewhere — the European certificate of suitability to the monographs of the European Pharmacopoeia is the closest analogue, though it differs in being an assessment rather than a repository.^[2]

The holder files the document with the regulator. When a customer submits an application using that substance, the holder issues a letter of authorisation permitting the regulator to review the file in support of that application.^[1]

The customer never sees the confidential content. This solves a genuine commercial problem: a manufacturer's process is often its principal asset, and disclosure to a customer who may be a competitor's supplier is unattractive.

Because review occurs only in the context of an application, an unreferenced file has never been assessed. A statement that a substance "has a DMF" therefore says that a document exists, not that it has been found adequate.^[1]

The last row matters here. A DMF describes a process and its controls for a substance intended as an active pharmaceutical ingredient. Material sold as a research chemical is not that substance in the regulatory sense, even where the chemistry is identical.^[3]

DMF numbers are published in regulator lists, so the existence of a filing is checkable. Its status generally is not.^[1]

• Active pharmaceutical ingredient
• Good manufacturing practice
• ISO 9001
• Certificate of analysis