An Active Substance Master File (ASMF), or formerly known as European Drug Master File (EDMF) procedure, is a set of documents that protects the valuable confidential intellectual property of the manufacturer. The purpose of an ASMF is to provide the Health Authorities (HAs) with complete information of the active substance used in a drug product to evaluate its suitability for the product. It also allows the Marketing Authorization Holder (MAH) of the product to take the responsibility for the quality of the active substance used in the product.

ASMF Content

An ASMF must contain all the scientific information related to the active substance. The information of an ASMF is divided into two parts:

  1. Applicant Part (AP) – Contains information considered as non-confidential by the MAH
  2. Restricted Part – Contains confidential information

ASMF Usage

An ASMF is submitted only to support a Marketing Authorisation Application (MAA) or Marketing Authorisation Variation (MAV). It is used for the following active substances:

  1. Active substances that are new
  2. Already existing active substances, which are excluded from the European Pharmacopoeia (Ph.  Eur.)
  3. Pharmacopoeial active substances, which are included in the (Ph. Eur.)

An ASMF holder is required to submit the following to the MAH holder:

  • A copy of AP’s latest version
  • A copy of the summary/detailed version of AP’s latest version
  • A copy of the letter of access, which has not been previously submitted for the same product

A single active substance can have both, an ASMF as well as a Certificate of Suitability (CEP). However, the MAH cannot refer to both the documents for a single active substance. In case, the information present in a CEP is insufficient, only then both the documents can be referred.

An ASMF is extremely important for the MAH as it contains confidential information related to the product. Authoring it within in defined compliance standards is advisable. Are you looking for Regulatory support to author ASMF? Reach out to us at