Guidance on Process Validation (PV 2011) uses the basic principles of scientific understanding put forth in ICHQ8—the foundation of Quality by Design (QbD)—to establish process understanding and link it to product reproducibility. It effectively abandons the old concepts of demonstrating process validation (IQ/OQ/PQ) and replaces it with a new, structured approach. It formalizes these principles by describing the level of product and process understanding necessary to satisfy the requirements of Stage 1 of the new PV guidance: Process Design, or QbD. To achieve this level of process understanding a framework that integrates product performance as part of process characterization is required. Simply put, the new PV guidance will make it much easier to justify moving toward QbD.
The challenge that many industry personnel face is bridging the gap between the former validation approach of “three batches and we’re done” to understanding how the new PV stages work together to establish process predictability. In practical terms, the new PV guidance describes the three stages as follows:
Stage 1 – Process Design (PD): The commercial manufacturing process is defined during this stage based on knowledge gained through development and scale-up activities.
Stage 2 – Process Performance Qualification (PPQ): During this stage, the process design is evaluated to determine if the process is capable of reproducible commercial manufacturing.
Stage 3 – Continued Process Verification: Ongoing assurance is gained during routine production that the process remains in a state of control, or Product & Process Control (P&PC)
Formula: PD + PPQ + P&PC = QbD