An appropriately-designed stress study meshes well with the QbD approaches currently being promoted in the pharmaceutical
industry. A well-designed stress study can provide insight in choosing the appropriate formulation for a proposed product
prior to intensive formulation development studies. A thorough knowledge of degradation, including mechanistic understanding
of potential degradation pathways, is the basis of a QbD approach for analytical method development and is crucial in setting
acceptance criteria for shelf-life monitoring. Stress testing can provide useful insight into the selection of physical form,
stereo-chemical stability of a drug substance, packaging, and storage conditions. It is important to perform stress testing
for generic drugs due to allowable qualitative and quantitative differences in formulation with respect to the RLD, selection
of manufacturing process, processing parameters, and packaging materials.
The author would like to thank Bob Iser, Naiqi Ya, Dave Skanchy, Bing Wu, and Ashley Jung for their scientific input and support.
Ragine Maheswaran, PhD, is a CMC reviewer at the Office of Generic Drugs within the Office of Pharmaceutical Science, under the US Food and Drug
Administration's Center for Drug Evaluation and Research, Ragine.Maheswaran@fda.hhs.gov
Disclaimer: The views and opinions in this article are only those of the author and do not necessarily reflect the views or policies
of the US Food and Drug Administration.
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