Change control ensures that any modification to facilities, processes or documents is assessed before implementation. Typical changes are classified as major, moderate and minor based on potential impact on product quality, patient safety and regulatory compliance.
Major changes are those that can significantly affect critical quality attributes or regulatory commitments. Examples include new manufacturing sites, addition of a new equipment train, changes to sterilisation or aseptic processes, new API suppliers, and revisions to product specifications or analytical methods that may alter release decisions. Major changes require formal risk assessment, validation or revalidation, possible stability studies, and prior approval from regulatory authorities where required.
Moderate changes (often called “moderate” or “level II” variations) have a lower but still meaningful risk. Typical examples are adjustments to non-critical process parameters within proven ranges, replacement of equipment with equivalent design, changes to primary packaging components of the same material, or updates to test methods without changing acceptance criteria. These changes still need documented risk assessment, protocol-driven verification, and timely regulatory notification according to regional guidelines.
Minor changes are low-risk adjustments with negligible impact on quality, safety or efficacy. Examples include editorial updates in SOPs without altering intent, relocation of non-critical utilities, format changes to batch records, or like-for-like replacement of instruments. Minor changes may be handled through streamlined workflows, such as simplified change proposals and effectiveness checks, while still maintaining full traceability.
Documentation for each category should define approvals, validation needs, stability requirements and regulatory pathways. Aligning classification with training, CAPA and lifecycle management helps teams act quickly on new knowledge and compliance changes while maintaining a practical, risk-based approach to change control.