Degradation studies regulatory requirements

Chapter 8 in Reference 2 reviews the many facets of stability studies and describes what a modern stability program includes. Efforts have been made to relate scientific considerations with regulatory requirements. Degradation kinetics is discussed later in this section to highlight their importance in monitoring and evaluating impurities.2... 

Because animals eliminate administered drugs and their metabolites directly into the environment via feces and urine, the decomposition of these products in water, via sunlight, and in various types of soil must be evaluated. In some cases even their effect on certain insects must be studied. Because of this regulatory requirement, an increased focus on the understanding of drug degradation pathways is conducted, which may not be undertaken for drugs used to treat humans. 

The degradation and formation of nonabsorbable drug complexes in the intestinal lumen is the third factor, in addition to dissolution and permeability, which could affect fraction absorption. Limitations of bioavailability due to these factors seem to be less frequent compared with the two other main factors. Regulatory guidelines for BCS-based biowaivers still ask for in vitro studies of luminal degradation in relevant test media, whereas specific binding studies are not required [17]. 

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