Missing Tests for Identity lead to FDA Warning Letter
Recommendation

Thursday, 3 September 2026 9 .00 - 17.00 h
Establishment, Use and Maintenance of Analytical Reference Substances
This FDA Warning Letter issued to Canadian manufacturer Cellex-C International, Inc. on 02 August, 2017 is based on an FDA inspection performed in January 2017.
The Warning Letter refers to the company's response from 07 August, 2017.
It was criticised that not all batches of the manufactured drug product and the active substances used therein had been tested for compliance with the specifications before their release.
According to the response given by Cellex-C, the tests had been performed by a contract laboratory. The FDA criticised in their warning letter that the response didn't give enough insight on how the selection, qualification and monitoring of said contract laboratory was conducted.
The FDA deems the response insufficient for two reasons:
For one thing, Cellex-C must at least perform a specific test for identity of all incoming materials. They may not rely on the supplier's analysis certificate alone.
Moreover, the company did not state how they would implement the missing tests on incoming materials for further issues besides the test for identity in the future.
Please also see the complete Cellex-C International, Inc. Warning Letter for more detailed information.
Related GMP News
12.08.2026ECA's Analytical Control Group Publishes Detailed Report on OOS Survey
12.08.2026BP Publishes Key Insights on Limits in Chromatographic Tests
04.08.2026BioPhorum Publishes a Roadmap for QC Sample Test Execution
04.08.2026USP AISQ Virtual Workshop: ECA AQCG Board Members Contributed as Speakers
04.08.2026Several FDA Warning Letters and Untitled Letters on Asbestos Testing of Talc in OTC Drug Products


