A Comprehensive Review on Assessment and Key Control Strategies for Impurities in Drug Development with a Special Emphasis on Post-marketing Surveillance

The presence of impurities is the primary cause of safety related drug product recall. Clinical data generated during the drug discovery process may not be able to conclude the long-term safety of a drug. The best way to ensure drug safety is to control the associated impurities. It can be achieved by a clear understanding of the route and factors for impurity formation. Tight control on manufacturing, storage, and transport process can provide a beneficial effect on minimization of impurity generation. Control strategies employing quality by design and risk assessment-based approaches potentially enhance drug safety profile and, thereby, minimize product recalls. Prior understanding of key aspects of the safety profile of impurities, post-marketing surveillance criticalities, and establishment of constructive preventive strategies is the best way to minimize unwanted product recall due to associated safety issues. Effective preventive strategies should be designed and executed during the product manufacturing and supply chain process. The novelty of this article can be justified by the unavailability of any similar type of reports discussing the functional pathway of regulatory bodies aiming for effective control of drug impurities. This article contains novel, critical, and constructive prevention strategies to establish a robust safety profile of pharmaceutical products.