Usage Examples
- Get the Letter of Authorization from the supplier before we commit to an ANDA filing date.
- The DMF holder changed the crystallization step and never notified us; we found out through an FDA information request.
- There is no approved DMF to point at, so the deficiency lands on our application, not theirs.
What is DMF (Drug Master File)?
A DMF is a standalone submission of confidential manufacturing, packaging, or excipient information that FDA reviews only when an application incorporates it by reference, letting a supplier support a customer's filing without disclosing trade secrets.
A DMF exists because two companies need FDA to see the same manufacturing detail while one of them refuses to show it to the other. An API supplier will not hand its route of synthesis to every generic customer. The DMF lets the supplier file that information directly with FDA and let customers rely on it without ever receiving it.
A DMF covers drug substances and their intermediates, drug product, packaging materials, excipients, colorants and flavors, and FDA-accepted reference information; the Type I slot is marked reserved in the regulation. A DMF is not an application and carries no approval status of its own. FDA ordinarily neither independently reviews nor approves one, examining it only inside a referencing IND, NDA, or ANDA.
A DMF is applied through written authorization. The holder issues a Letter of Authorization naming what a specific applicant may use, keeps a current list of every authorized person inside the file, and notifies each of them in writing whenever the file changes. The applicant then cites the material by name, reference number, volume, and page number.
Not to be confused with
- NDA / ANDA
- an NDA or ANDA is an application seeking approval to market a product. A DMF is never approved on its own; it only supports the application that references it, and deficiencies land on that application.
- Letter of Authorization
- the LOA is the written permission that lets one named applicant incorporate specified DMF material by reference. It is the instrument, not the file, and it conveys no access to the file's contents.
- CMC
- CMC is the whole body of chemistry, manufacturing, and controls information a product needs. A DMF is one delivery mechanism for the slice of that package a third party will not disclose to the applicant.
- Incorporation by reference
- the act, not the file. A DMF can sit with zero authorized users; an incorporation by reference is the specific citation of named material by reference number, volume, and page number inside a submission.
The obligations sit on both sides of the reference: the holder maintains the file, the applicant cites it correctly.
What you must do
- 1Obtain the holder's written authorization before an IND, NDA, ANDA, amendment, or supplement incorporates any part of a DMF21 CFR 314.420(b)
- 2Describe every incorporation by reference by name, reference number, volume, and page number of the drug master file21 CFR 314.420(b)
- 3Maintain inside the file a complete list of each person currently authorized to incorporate by reference, identifying exactly what each may use21 CFR 314.420(d)
- 4Include the name of each drug product and its application number in that list wherever the authorization is restricted to particular products21 CFR 314.420(d)
- 5Notify each authorized person in writing whenever information in the file is added, changed, or deleted21 CFR 314.420(c)
- 6Submit a letter of intent to the Drug Master File Staff before filing information not covered by Types II through IV21 CFR 314.420(a)(5)
Common mistakes
Treating the DMF as an approval
FDA ordinarily neither independently reviews nor approves a drug master file, so "our supplier has an approved DMF" is not a status that exists. The first real review happens against your application, on your review clock, and every deficiency is yours to resolve through a supplier you do not control.
Letting the authorization list go stale
the file must carry a complete list of every currently authorized person and exactly what each may reference. When a customer is added, a product is renamed, or an application number changes, an out-of-date list breaks the reference chain and the applicant's citation points at nothing.
Changing the file without notifying customers
the holder must tell each authorized person in writing about any addition, change, or deletion. Applicants who discover a process change through an FDA information request lose weeks reconstructing what happened, and usually lose confidence in the supplier at the same time.
When This Matters
- Get the Letter of Authorization from the supplier before we commit to an ANDA filing date.
- The DMF holder changed the crystallization step and never notified us; we found out through an FDA information request.
- There is no approved DMF to point at, so the deficiency lands on our application, not theirs.
Frequently Asked Questions
A Type II DMF holds information on a drug substance, drug substance intermediate, and materials used in their preparation, or on a drug product. It is the type most API manufacturers maintain, because it is where the route of synthesis, process controls, and impurity data sit that a customer never sees.
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