Critical process parameter (CPP)

A process parameter whose variability affects a critical quality attribute and which should therefore be monitored or controlled, as defined in ICH Q8. CPPs are identified through risk assessment and experiments such as design of experiments. In Japan the label matters for filings. According to PMDA, critical process parameters are treated as established conditions and are described in the manufacturing method section of the application. MHLW's examples treat a change to a critical parameter, such as sterilization conditions, as a partial change application, while changes to other parameters, such as manufacturing scale, can be minor changes.