FDA WARNING_LETTER - RHYZ ANALYTICAL LABS - June 05, 2025

On November 12, 2025, the FDA issued a Warning Letter to Rhyz Analytical Labs following an inspection from June 2 to 5, 2025, at their Provo, UT facility. The letter detailed significant violations of Current Good Manufacturing Practice (CGMP) regulations, rendering drug products tested by the company adulterated under the Federal Food, Drug, and Cosmetic Act.

Key violations included the firm"s failure to thoroughly investigate unexplained discrepancies or out-of-specification (OOS) results, particularly for microbiological tests. Rhyz Analytical Labs repeatedly concluded "unknown laboratory error" without sufficient scientific justification, relying on retest data without proper root cause analysis, and failing to assess the effectiveness of corrective and preventive actions. Additionally, the company"s Quality Unit failed to establish adequate written responsibilities and procedures, demonstrating insufficient oversight of contract testing operations, including critical processes like deviations, change control, cleaning, and laboratory investigations.

The FDA deemed the company"s responses to these observations inadequate. Rhyz Analytical Labs is required to conduct a retrospective, independent review of all invalidated OOS results from the past three years, providing scientific justification and a remediation plan for vulnerable laboratory methods. They must also submit a comprehensive remediation plan for their OOS investigation systems, addressing Quality Unit oversight, trend identification, root cause resolution, and revised procedures. Furthermore, a comprehensive assessment and remediation plan for the Quality Unit is mandated to ensure its effective functioning, including robust procedures and adequate oversight. Failure to address these violations promptly may lead to further regulatory action.