FDA-Investigating Out-of-Specification (OOS) Test Results for Pharmaceutical Production

This guidance for industry provides the Agency’s current thinking on how to evaluate out-ofspecification (OOS) test results. For purposes of this document, the term OOS results includes all test results that fall outside the specifications or acceptance criteria established in drug applications, drug master files (DMFs), official compendia, or by the manufacturer. The term also applies to all in-process laboratory tests that are outside of established specifications. This guidance applies to chemistry-based laboratory testing of drugs regulated by CDER. It is directed toward traditional drug testing and release methods. These laboratory tests are performed on active pharmaceutical ingredients, excipients and other components, in-process materials, and finished drug products  to the extent that current good manufacturing practice (CGMP) regulations (21 CFR parts 210 and 211) and the Federal Food, Drug, and Cosmetic Act (the Act) (section 501(a)(2)(B)) apply. The principles in this guidance also apply to in-house testing of drug product components that are purchased by a firm. This guidance can also be used by contract firms performing production and/or laboratory testing responsibilities. Specifically, the guidance discusses how to investigate OOS test results, including the responsibilities of  laboratory personnel, the laboratory phase of the investigation, additional testing that may be necessary, when to expand the investigation outside the laboratory, and the final evaluation of all test results.

The Agency, in accordance with its August 2002 “Pharmaceutical CGMPs for the 21st Century” initiative, encourages modern approaches to manufacturing, monitoring, and control to enhance process predictability and efficiency. Process Analytical Technology (PAT) takes a different approach to quality assurance by using process controls and in-process data as the release specification instead of relying on single laboratory determinations to make batch acceptability decisions. This guidance is not intended to address PAT approaches, as routine in-process use of  these methods might include other considerations. For information on timely in-process testing,see the CGMP guidance entitled PAT — A Framework for Innovative Pharmaceutical Development, Manufacturing, and Quality Assurance. 

FDA's guidance documents, including this guidance, do not establish legally enforceable responsibilities. Instead, guidances describe the Agency's current thinking on a topic and should be viewed only as recommendations, unless specific regulatory or statutory requirements are cited. The use of the word should in Agency guidances means that something is suggested or recommended, but not required. 

II. BACKGROUND

Laboratory testing, which is required by the CGMP regulations (§§ 211.160 and 211.165), is necessary to confirm that components, containers and closures, in-process materials, and finished products conform to specifications, including stability specifications. Testing also supports analytical and process validation efforts.4 General CGMP regulations covering laboratory operations can be found in part 211, subparts I (Laboratory Controls) and J (Records and Reports). These regulations provide for the establishment of scientifically sound and appropriate specifications, standards, and test procedures that are designed to ensure that components, containers and closures, in-process materials, and finished drug products conform to the established standards. Section 211.165(f) of the CGMP regulations specifies  hat finished drug products that fail to meet established standards, specifications, or other relevant quality control criteria will be rejected.

Both finished pharmaceuticals and active pharmaceutical ingredients (APIs) are to be manufactured in accordance with current good manufacturing practice under section 501(a)(2)(B) of the Act. Current good manufacturing practice for APIs includes the performance of scientifically sound raw material testing, in-process monitoring, release and stability testing, process validation, and adequate investigations of any OOS result obtained from such testing. All citations to part 211 in this document pertain to finished pharmaceuticals, but these referenced regulatory requirements are also consistent with Agency guidance on CGMPs for PIs with respect to laboratory controls, which include out-of-specification investigations. See FDA’s guidance for industry Q7A Good Manufacturing Practice Guidance for Active Pharmaceutical Ingredients (ICH Q7A) for specific recommendations. The responsibility of a contract testing laboratory in meeting these requirements is equivalent to that of a manufacturing firm.