FDA Warning Letter: Missing Stability Testings

In October 2025, the U.S. FDA issued a Warning Letter (WL) to the US American company "Dixon Investments Inc. dba ARI" after having inspected its site in March 2025.

The significant violations of CGMP regulations for drug product, which are mentioned in the Warning Letter, are listed as follows:

• "Your firm failed to establish adequate written procedures for production and process control designed to assure that the drug products you manufacture have the identity, strength, quality, and purity they purport or are represented to possess (21 CFR 211.100(a))."
  
• "Your firm failed to follow an adequate written testing program designed to assess the stability characteristics of drug products and to use results of stability testing to determine appropriate storage conditions and expiration dates (21 CFR 211.166(a))."
  
• "Your firm's quality control unit failed to exercise its responsibility to ensure drug products manufactured are in compliance with CGMP, and meet established specifications for identity, strength, quality, and purity (21 CFR 211.22)."

According to U.S. FDA Warning Letter, the firm failed to "test an adequate number of drug product batches as defined by their written stability procedure". This is a repeated finding which caused a long list of remediation activities and CAPA measurements requested by the U.S. FDA. Additionally, it is mentioned that these repeated findings let to the conclusion that the quality oversight of the management is inadequate.

Coming to the final conclusion mentioned in the Warning Letter, the U.S. FDA may refuse new applications listing the company as drug manufacturer and export certificates until the site has addressed all observations and fully complies with CGMP requirements, which might be checked by a further inspection.

To view the complete list of violations and the conclusion given by the U.S. FDA, please see the Warning Letter Dixon Investments Inc. dba ARI.