Systematic Implementation of Quality by Design (QbD): A Perspective from Generic Pharmaceutical Industries

Quality by Design (QbD) is a structured approach to pharmaceutical development that ensures predefined product quality by understanding and controlling manufacturing processes from the outset. Unlike traditional methods focusing on end-product testing, QbD emphasizes building quality into the product design itself, enhancing manufacturing efficiency and regulatory compliance. This review highlights the application of QbD in developing generic solid oral drug products, emphasizing tools like risk assessment, process design, and control strategies to achieve consistent quality. Key components include identifying and managing Critical Quality Attributes (CQAs), Critical Process Parameters (CPPs), and Critical Material Attributes (CMAs), which influence formulation, process development, and overall performance. The integration of Design of Experiments (DoE) to systematically study the effects of multiple variables on product and process performance, enabling optimization and robust development and effective control strategies are also discussed in this article. Addressing regulatory expectations, particularly those from the International Council for Harmonisation (ICH), this review outlines how QbD principles help generics meet bioequivalence standards, ensuring consistent quality and performance. Applying QbD not only enhances product robustness and manufacturing efficiency but also improves patient safety through better process understanding and continuous improvement. This review article outlines the various steps involved in the development of generic drug products using the QbD approach from analysis of brand product to product lifecycle management and continual improvement.