Impurities in Oncology Pharmaceuticals: A Review of Classification, Detection Methods, Regulatory Frameworks and Emerging Trends.

Pharmaceutical impurities pose a significant challenge in the development and manufacturing of anti-cancer drugs due to their high potency, narrow therapeutic index, and prolonged administration in most treatment regimens. Even trace-level impurities can compromise drug safety, efficacy, and regulatory compliance. This review provides a comprehensive overview of various types of pharmaceutical impurities organic, inorganic, residual solvents, and genotoxic impurities with a focus on their origins, toxicological significance, and impact on oncology therapeutics. The paper discusses traditional and modern analytical methods used for impurity detection, including chromatographic techniques, spectroscopic tools, mass spectrometry, and capillary electrophoresis and advanced hyphenated systems. Regulatory frameworks from International Council for Harmonization, the U.S. Food and Drug Administration, the European Medicines Agency, Therapeutic Goods Administration, Medicines and Healthcare products Regulatory Agency and the World Health Organization are examined, particularly concerning acceptable limits for genotoxic and elemental impurities. In addition, this study explores recent advancements such as surface plasmon coupled emission technique, AI-assisted data analysis, portable sensors, and real-time monitoring technologies that enhance impurity profiling. The advantages and applications of the modern technologies are discussed, emphasizing their role in improving method efficiency, automation, and sustainability in connection with the impurity profiling.