Continued Process Verification, 3rd Stage of FDA Process Validation Guidelines

Continued Process Verification (CPV), the 3rd Stage of the FDA process validation guidelines, represents the Ship of Theseus in bioprocessing:

• The bioprocess is validated and on the market, but it inevitably is subject to changes in supplies, raw materials, equipment and parameters.
• At what point is the process no longer in its original validated state?
• CPV seeks to prove that the process does not leave its validated state, despite various changes to the process.

Continued Process Verification can take a number of forms, but at its core, it is a study plan with a list of parameters and attributes that must be regularly controlled and observed during the lifecycle of the GMP bioprocess. Review at regular intervals is critical to ensure that the changes are not having an impact on present results.

The primary reasons for creating a Continued Process Verification plan are not only to achieve compliance with regulatory authorities, but also to prevent batch discards, mitigate process vulnerabilities, and find continuous improvement possibilities. Various important considerations are also discussed, including which data may be included in a Continued Process Verification plan, with what frequency should the attributes be monitored, and what level of statistical sophistication is required.

Lastly, the importance of data integrity is discussed, wherein the transfer of many different data sources to a centralized single-source-of-truth is critical to ensure that the data analysis is robust and reveals the correct signals to investigate.