An OOS result is generated when a drug product undergoing release testing or stability testing fails to meet an expected result or specification. When this happens, the FDA requires a valid reason must be determined to invalidate the OOS result and therefore an investigation into the cause of the OOS result must be conducted.
OOS Related Inspection Questions
•Show me a list of OOS results from the last 6 months?
•What is the procedure for OOS situations?
•Are SOPs followed?
•Are initial investigations made in a timely manner?
•Are full investigations made in a timely manner (where necessary)?
•Are investigations documented properly?
•Are investigation findings subject to proper review?
•Does the procedure include root cause analysis, impact analysis, and corrective actions and preventive actions?
Avoid Analytical Instrument Related OOS
•Regular method re-validation
•Instrument qualification (initial, after changes, after repairs etc)
•Operator qualification
•Qualification of reference material and reagents(stability, purity, accuracy)
•Preventive maintenance for equipment and computer hardware (seal, lamps)- based on usage
•Trend charts of critical instrument and method parameters
Avoid Product Related OOS
•Process analytical technology
–Get a good understanding of the process
–Uncover and fix critical process parameters
–Reduces process variability
–Can interfere in production process based on results of intermediate steps
•Setting meaningful specifications
–Set specifications based on mature process not on pilot results or ‘tentative’ registration specifications
–Update specifications based on experience and statistical evaluations