Why Your CDMO’s Inspection Record Is Your Problem Too
When a regulatory agency inspects a contract manufacturing organisation, it is not just inspecting the CDMO. It is inspecting the GMP compliance of every product made at that site, including yours.
A Form 483 observation or a warning letter to your CDMO does not automatically stop your programme, but it can. Regulators may place a clinical hold, request additional manufacturing information, or delay the approval of a marketing authorisation application if there are unresolved GMP concerns at a manufacturing site named in the submission. Understanding how inspections work, and what questions to ask your CDMO before one happens, is basic programme risk management.
How Inspections Are Triggered
Routine Surveillance Inspections
The FDA inspects domestic manufacturing sites roughly every two years and foreign sites less frequently, prioritising those associated with products marketed in the US. EU national competent authorities inspect licensed sites on a risk-based schedule, typically every three to five years. These routine inspections are not triggered by any specific concern and are a normal part of operating a GMP facility.
Application-Based Inspections
When a new drug application, biologics licence application, or marketing authorisation application names a manufacturing site, regulators may conduct a pre-approval inspection (PAI) to verify that the site is capable of manufacturing the product as described in the application. A PAI finding that identifies significant GMP deficiencies can delay approval or require a complete response.
For-Cause Inspections
A for-cause inspection is triggered by a specific concern, such as a product recall, a serious adverse event with a potential manufacturing cause, a whistleblower complaint, or unsatisfactory results from a prior inspection. These inspections are more intensive than routine surveillance and carry higher risk of serious regulatory action.
What Inspectors Look For
| Inspection Focus Area | What the Inspector Is Assessing | Common Finding |
| Data integrity | Are records accurate, complete, and attributable? Can the inspector trace every action to a person and a time? | Electronic records without adequate audit trails; backdated entries; deletions without justification |
| Change control | Are manufacturing changes properly assessed, approved, and reflected in regulated documents? | Changes implemented without formal change control; regulatory filings not updated |
| Out-of-specification investigations | Are OOS results properly investigated? Are invalidated results justified? | OOS investigations closed prematurely; root cause attributed to human error without adequate evidence |
| Contamination control | Are cleaning validation, environmental monitoring, and personnel practices adequate? | Environmental monitoring exceedances not investigated; cleaning validation data gaps |
| Batch record review | Are batch records complete and do they reflect the actual manufacturing process? | Unexplained corrections; missing critical in-process data; batch records not reflecting deviations |
| CAPA effectiveness | Are corrective actions actually preventing recurrence? | Repeat deviations for the same root cause; CAPA closed before effectiveness verified |
Questions Sponsors Should Ask Their CDMO
You have a right to understand the inspection history of any facility manufacturing your product. The following questions are reasonable and professional to ask before engaging a CDMO and at regular intervals during a manufacturing relationship.
- When was the facility last inspected and by which authority?
- Were there any findings (Form 483 observations or Warning Letters from the FDA; critical or major findings from EU inspectors)?
- How were those findings resolved? Can you share the response?
- Is any ongoing regulatory correspondence active relating to GMP compliance at this site?
- How are inspection preparation activities managed, and can the sponsor attend a mock inspection?
How a Well-Prepared CDMO Handles an Inspection
A GMP-mature CDMO treats inspection readiness as a continuous state, not a sprint that happens when an inspection notice arrives. Documentation is current, deviations are closed or actively progressed, and the quality team can answer questions about any product or process without scrambling for information.
When an inspection begins, the CDMO’s quality leadership manages the interaction professionally, provides accurate and complete information, and does not make commitments on behalf of sponsors without appropriate coordination. Sponsors are notified promptly when their product or process is discussed during an inspection.
Ardena’s Inspection Track Record
Ardena’s manufacturing sites are subject to regular inspection by national competent authorities in Belgium, the Netherlands, and Spain, as well as by the US FDA for sites that supply products to the US market. The quality teams at each site maintain inspection-readiness as a core operational discipline, with regular internal audits and a proactive approach to managing open findings.
