WHO-GMP, USDMF, and CEP: What to Check Before Choosing an API Manufacturer in India
                     WHO-GMP, USDMF, and CEP: What to 
Check Before Choosing an API 
Manufacturer in India 
India hosts more USFDA-compliant pharmaceutical manufacturing facilities than any 
country outside the United States, according to India Brand Equity Foundation data, and 
its more than 500 API manufacturers account for an 8 percent share of global API 
value. That scale creates real variation in regulatory readiness. Two manufacturers 
producing the same molecule, such as piroxicam or furosemide API, can carry very 
different documentation packages depending on which markets they have historically 
exported into. 
Three documents do most of the work in a supplier qualification file: the WHO-GMP 
certificate, the US Drug Master File, and the European Certificate of Suitability. Each 
answers a different regulatory question, and a formulator who understands what each 
one actually confirms can qualify an Indian API manufacturer faster and with fewer 
surprises during their own product's review. 
What a WHO-GMP Certificate Actually Confirms 
A WHO-GMP certificate is issued by a national regulatory authority, in India's case the 
Central Drugs Standard Control Organisation together with state licensing authorities, 
after an inspection confirms a manufacturing site meets the production and quality 
control standards set out in WHO Technical Report Series guidance. The certificate 
applies to a specific manufacturing site and product category, not to a company as a 
whole, so a formulator should confirm the certificate actually covers the API and 
manufacturing block being sourced from, not simply that the company holds a WHO-
GMP certificate somewhere in its portfolio. 
WHO-GMP certification is typically the minimum bar for exporting API into markets 
across Africa, Southeast Asia, and Latin America, and it also functions as a baseline 
credibility signal for buyers in more heavily regulated markets before deeper due 
diligence begins. It does not, on its own, confirm the site has passed a US FDA or EU 
inspection, which is why buyers targeting those markets need to look further. 
The US Drug Master File: Type II Filings and What to Ask For 
A Type II Drug Master File is the mechanism an API manufacturer uses to share 
confidential manufacturing and quality data with the US FDA without disclosing it 
directly to the formulator referencing it. The manufacturer files the DMF, receives a filing 
number, and the formulator's own abbreviated new drug application references that 
number, which lets the FDA cross-check the API data during its review of the finished 
product. A formulator sourcing metoprolol succinate or metoprolol tartrate API for a US-
bound ANDA should confirm the DMF number is active and has not received a 
deficiency letter that remains unresolved. 
Filing a DMF does not guarantee it will be reviewed favorably, since the FDA only 
evaluates a DMF's content in the context of a specific ANDA that references it. Buyers 
should ask the manufacturer how many ANDAs currently reference their DMF for the 
molecule in question, since a DMF with multiple successful references carries more 
practical assurance than one that has never been tested through an actual FDA review 
cycle. 
The European Certificate of Suitability (CEP): When It Matters 
A Certificate of Suitability, issued by the European Directorate for the Quality of 
Medicines, confirms that an API manufacturer's process and quality controls are 
suitable to meet the relevant European Pharmacopoeia monograph. It serves a similar 
function to a DMF but is specific to the EU regulatory framework, and unlike a DMF, the 
CEP itself is a public document that formulators can verify directly through the EDQM 
database rather than relying solely on the manufacturer's representation. 
A CEP matters most for formulators filing into EU member states or other markets that 
accept CEPs as part of a simplified quality dossier. For a molecule like 
hydrochlorothiazide or piroxicam API, where the European Pharmacopoeia monograph 
is well established, a current CEP substantially shortens the quality section of a 
marketing authorisation application compared with submitting full manufacturing data 
independently. 
Matching Documentation to Molecule: Furosemide, 
Metoprolol, Piroxicam, and Hydrochlorothiazide 
Documentation depth varies by molecule maturity in a given manufacturer's portfolio. A 
well-established furosemide API manufacturer with years of export history typically 
holds an active DMF, a CEP, and multiple national GMP certificates, since the molecule 
has moved through many buyers' qualification processes already. A piroxicam API 
supplier serving a smaller, more specialised buyer base may hold WHO-GMP and a 
national GMP certificate without yet carrying a US DMF, which is not disqualifying but 
does mean the buyer should confirm what documentation timeline the manufacturer can 
commit to if a US filing is planned. 
For metoprolol succinate and metoprolol tartrate API, request documentation specific to 
each salt form rather than assuming shared paperwork, since the two are filed and 
monographed separately. Hydrochlorothiazide API sourcing should include confirmation 
of compatibility data with the specific combination partners a formulator plans to use, 
since regulators increasingly expect combination-specific stability evidence rather than 
single-molecule data alone. 
Site Inspection History: Reading Between the Certificates 
A current certificate confirms a facility passed its most recent inspection, but it does not 
show the inspection history that led there. Ask for the manufacturer's most recent 
inspection observations, whether from CDSCO, WHO, USFDA, or an EU authority, and 
how the site closed out any findings. A site with a documented, closed-out corrective 
action history demonstrates a functioning quality system more convincingly than a 
certificate with no visible inspection record behind it. 
Publicly available USFDA inspection classification data, when a site has been inspected 
by the agency, is a useful independent cross-check against what a manufacturer 
represents during supplier qualification. Buyers evaluating a metoprolol or 
hydrochlorothiazide API manufacturer with US FDA inspection history should review the 
agency's published classification for that site before relying solely on the manufacturer's 
own summary. 
Building a Documentation Checklist Before You Issue an 
RFQ 
Document Issuing Body What It Confirms 
WHO-GMP Certificate National authority (CDSCO in Site meets WHO Technical 
India) Report Series manufacturing 
standards 
US DMF (Type II) US FDA Confidential manufacturing 
data available for ANDA 
cross-reference 
CEP EDQM Process meets European 
Pharmacopoeia monograph 
requirements 
Site Master File Manufacturer, reviewed at Overview of facility, 
inspection equipment, and quality 
systems 
Stability Data (ICH zone) Manufacturer API stability under 
destination-market climatic 
conditions 
Request every document on this list before issuing a purchase order, not after. A 
manufacturer's willingness to share this documentation promptly during the RFQ stage 
is itself informative: a supplier confident in its regulatory position rarely hesitates to 
provide it. 
Frequently Asked Questions: API Manufacturer 
Documentation 
What is the difference between a DMF and a CEP? 
A Drug Master File is filed with the US FDA and remains confidential except to the 
agency, while a Certificate of Suitability is issued by EDQM and is publicly verifiable. 
Both confirm an API manufacturer's process meets the relevant regulatory quality 
standard, but they serve different markets and filing pathways. 
Does a WHO-GMP certificate cover every product a manufacturer makes? 
No. A WHO-GMP certificate applies to a specific manufacturing site and product 
category confirmed during inspection, not to a company's entire portfolio. Buyers should 
confirm the certificate specifically covers the API and production block they intend to 
source from. 
How can a buyer verify a manufacturer's CEP is genuine? 
The European Directorate for the Quality of Medicines maintains a public database 
where buyers can search a CEP by manufacturer name or reference number. This lets 
a formulator confirm a certificate's validity independently rather than relying only on the 
manufacturer's documentation. 
Why would an API manufacturer not hold a US DMF? 
Filing and maintaining a US DMF costs money and administrative effort, so 
manufacturers serving markets that do not require it, such as parts of Africa, Southeast 
Asia, or Latin America, may not maintain one. This is not automatically disqualifying, but 
buyers planning a US filing should confirm a realistic timeline for the manufacturer to file 
one. 
What should a buyer ask about a manufacturer's inspection history? 
Ask for the most recent inspection observations from any regulatory authority, WHO, 
USFDA, CDSCO, or an EU authority, and how the manufacturer closed out any 
findings. A documented corrective action history shows more about quality system 
maturity than a certificate alone. 
Is a CEP more useful than a DMF for an EU-bound product? 
Yes, for EU filings a current CEP is generally more directly useful since it maps to the 
European Pharmacopoeia monograph a marketing authorisation application will 
reference. A DMF remains the relevant document for US-bound filings instead. 
Documentation Is the Cheapest Due Diligence You Will Do 
Every hour spent verifying a WHO-GMP certificate, a DMF filing status, or a CEP 
reference before committing to a supplier costs far less than discovering a 
documentation gap after a regulatory agency raises it during review of the finished 
product. The manufacturers worth building a long-term cardiovascular or anti-
inflammatory API supply relationship with are the ones that treat this documentation as 
readily available, not as something to produce only under pressure. 
As more buyers diversify their API sourcing away from single-country dependence, the 
manufacturers that can produce a complete, current documentation package on request 
will absorb a growing share of that shifting demand.