In the most recent GMP Trends Report, one firm was cited for failing to adequately investigate out-of-specification (OOS) results, instead relying on repeated retesting to invalidate initial failures.
“…..The responsibilities and procedures applicable to the quality control unit are not in writing and fully followed.
Specifically, SOP …,“Test Out of Specification (OOS)”, is inadequate and not followed in that investigations are not always conducted for OOS results. Additionally, your firm’s practice is to retest OOS results … times, which can be used to invalidate initial OOS results without further investigation and documentation.”
FDA investigators noted that no scientific justification or documentation accompanied the decision to disregard original OOS data. This practice runs counter to 21 CFR 211.192, which requires that “any unexplained discrepancy… shall be thoroughly investigated, whether or not the batch has already been distributed.” In accordance with FDA OOS guidance, a written record of the investigation shall be made and shall include the conclusions and follow-up.
OOS results must be scientifically investigated, not dismissed through repeated testing. By retesting until a passing result is achieved, without root-cause analysis or documented justification, firms risk distributing products with unknown quality defects.
