1. The Anatomy of a Drug Master File (DMF)
A Drug Master File is a confidential dossier submitted to regulatory authorities (such as the US FDA or EDQM) containing detailed information about the chemistry, manufacturing, and controls (CMC) of an active ingredient.
In commercial procurement, buyers receive the Applicant's Part (Open Part), which details specifications, stability data, analytical procedures, and packaging systems without exposing the manufacturer's proprietary synthesis route (Restricted Part).
- Type II DMF: Active Pharmaceutical Ingredients, drug substance intermediates, and materials used in their preparation
- Open Part (Applicant's Part): Shared with pharmaceutical formulators for submission in regulatory dossiers
- Letter of Access (LoA): Formal authorization permitting regulatory review of the supplier's confidential file on behalf of the buyer
2. WHO-GMP and Site Regulatory Audits
A valid WHO-GMP certificate issued by the competent national drug control authority (such as CDSCO in India) affirms that the manufacturing facility operates under rigorous cleanliness, process validation, air handling (HVAC), and cross-contamination prevention standards.
Buyers should verify certificate validity, inspection dates, and the specific list of approved synthetic blocks on the license annexures.
Frequently Asked Questions
What is a Letter of Access (LoA)?
An LoA is a formal legal instrument provided by the API manufacturer to regulatory agencies granting permission to reference their DMF in connection with a specific applicant's drug application.
Can an API with an active DMF be substituted across suppliers without regulatory filing?
No. Sourcing an API from an alternate supplier constitutes a variation or post-approval change requiring regulatory notification and comparative stability testing.
Summary & Procurement Recommendation
Selecting verified API manufacturers with robust regulatory documentation ensures frictionless market approvals and uninterrupted commercial manufacturing.