Regulatory aspects of Impurity profiling

Quality, safety and efficacy of pharmaceuticals play an important role in drug therapy. The safety attribute of drug is established by its pharmacological or toxicological profile along with adverse effects caused by impurities in bulk and dosage form. Impurities present in drug often possess undesired pharmacological or toxicological effects which outweighs the benefits of drug therapy. Recently, many impurity cases have been reported for e.g. NDMA (N-nitroso dimethylamine) impurity in drug product Ranitidine. This may be due to inappropriate follow of impurity related regulatory guidelines or critical voids in regulatory control of impurities or may be lack of appropriate analytical technique for impurity detection. Moreover, in June 2007, EMA became aware of contamination of Viracept® tablets. It was detected with presence of ethyl mesylate impurity, a known genotoxic substance in Nelfinavir mesylate (Viracept®). Due to this, the product was recalled from EU market. An impure drug is devoid of safety, quality and efficacy and can lead to adverse events. So, drugs of required quality standards should reach the market for patient’s safety. Therefore it is important and becomes mandatory to submit impurity data related to isolation, identification, qualification and control of impurities to respective regulatory authorities. This article is an attempt to deliver comprehensive understanding related to various attributes and details about impurity profiling in context with regulatory guidelines along with detail description of impurity data submission to regulatory authority for drug substance (API) to get market approval. This article also focus on ICH impurity guidelines ,sources, classification and quality control of impurities.