Implementation of Quality by Design in Generic Drug Product Development: A Case Study Using Diclofenac Sodium Sustained Release Tablets

Abstract

The current study aims to implement Quality by Design (QbD) principles in the development of generic products to establish a robust, consistent, and regulatory-compliant formulation. Diclofenac Sodium was selected as a model drug to develop a sustained-release tablet formulation. Voveran^® SR 100mg Tablets were used as the reference-listed drug (RLD), and the Quality Target Product Profile and Critical Quality Attributes were delineated. Key formulation variables affecting drug release and hardness were identified using initial risk assessment. A 2^5-1 fractional factorial design was employed for screening significant factors influencing the formulation attributes. The formulations were further optimized using a Central Composite Design to define a design space, ensuring steady drug release and hardness. The desirability approach was used to confirm the optimal conditions and make the point predictions. The actual values aligned very closely with the predictions made by the model. The optimized formulations demonstrated drug release of 80-100% after 12 hours and hardness between 70-130 newtons. The optimized formulation showed excellent similarity with RLD, with an F2 value of more than 50. This study underscores the efficacy of QbD in pharmaceutical development, demonstrating its role in achieving predefined quality standards and regulatory compliance while fostering continuous improvement.