Drug master files serve as documentation on the quality of an active ingredient or excipient and are submitted by a manufacturer as part of the licensing or amendment procedure.

Drug master file (DMF) is set of documents submitted to FDA by a pharma manufacturer, the drug master file may also provide information which may be confidential for the company but may be required to be presented to regulatory authority for complete understanding of their product, facility, and the processes, systems, equipments and articles adapted for various of process of manufacturing and quality control and quality assurance, or storage and distribution.

For submission to European countries it is called as Active Substance Master File (ASMF) European Drug Master File (EDMF) and it is also called US-Drug Master file (US-DMF) in United States.

It is not mandatory document for US FDA, but it is submitted by a pharmaceutical manufacturer to support their export application or (ANDA) Abbreviated New Drug Application, IND Investigational New Drug Application , or (NDA) New Drug Application. FDA reviews DMF only in context with these applications and an application for marketing a new drug in market.

The types of DMFs are :

• Type I Manufacturing Site, Facilities, Operating Procedures, and Personnel (no longer applicable)
• Type II Drug Substance, Drug Substance Intermediate, and Material Used in Their Preparation, or Drug Product
• Type III Packaging Material
• Type IV Excipient, Colorant, Flavor, Essence, or Material Used in Their Preparation
• Type V FDA Accepted Reference Information

A drug master file comprises two parts: the Applicant’s Part (USA: Open Part), which contains all the information that the licence-holder needs to assess the quality and submit a licence or amendment application; and the Restricted Part (USA: Closed Part), which contains confidential information about the manufacturing procedure that only needs to be disclosed to the authorities.

The drug master file must be submitted in the format described in the Common Technical Document (CTD) Part 3.2.S. Exceptions are defined