Answer: A PQS establishes a state of control across the four product lifecycle stages (Development, Technology Transfer, Commercial Manufacturing, and Product Discontinuation). The four core enablers and management pillars are:
- ​Process Performance and Product Quality Monitoring System: Tracking critical process parameters (CPPs) and critical quality attributes (CQAs).
- ​Corrective Action and Preventive Action (CAPA) System: Identifying root causes through systematic problem-solving (e.g., Fishbone, 5-Whys) and requiring mandatory effectiveness checks.
- ​Change Management System: Formal risk-based evaluation before introducing any changes to equipment, facilities, utilities, raw materials, or analytical methods.
- ​Management Review: Periodic evaluation of quality performance indicators, internal audits, customer complaints, and CAPA timeliness by senior executive management.