Critical Process Control Essay

A critical process parameter (CPP) is “a process parameter whose variability has an impact on a critical quality attribute (CQA) and therefore should be monitored or controlled to ensure the process produces the desired quality” A . Identifying the CPPs for a process is therefore dependent on knowing the CQAs for the process. Knowledge of CPPs and other critical aspects of process control are vital for defining the control strategy for a process to assure consistent control of product quality. Development and process experience provide this knowledge, including the acceptable ranges and/or design space boundaries for the process, the appropriate reliability and precision of process controls and the probable adverse consequences and risks of operating outside the identified acceptable ranges.

Validation of the process, by bringing a focus on CPPs and other critical aspects of process control, will provide confirmation that the process control strategy is effective in assuring product quality. CPPs are typically identified during process development. Steps for identifying CPPs can be summarized as follows

1. Ensure CQAs have already been identified for the product. Prior knowledge of the CQAs for a process, which are typically identified in regulatory filings, is essential for identifying the CPPs. The CQAs are physical, chemical, biological, or microbiological properties or characteristics that should be within an appropriate limit, range, or distribution to ensure the desired product quality. CQAs for intermediates also contribute to the control strategy for a process.
2. Identify inputs (process parameters and critical aspects) that impact the CQAs (outputs).
3. Establish a correlation between CQAs and PPs. understand how these parameters and critical aspects impact CQAs. Laboratory and pilot-scale models designed to be representative of the commercial process may be used to