Purpose: Pharmaceutical excipients are essential components of most modern dosage forms and play a critical role in the drug product’s development, delivery, effectiveness and stability. Because excipients are a group of heterogeneous materials, they can range from simple, well-characterized substances to more complex, including mixtures of related components or other components. As a result they can significantly differ in origin (natural: plant, animal and mineral; semi-synthetic, and synthetic), physical, and chemical characteristics and can be produced by different manufacturing processes. As such, understanding of the excipient composition is the key element in the drug product development.
Methods: An excipient composition can be defined as a set of components comprising the material used as a pharmaceutical excipient in drug products. Classification of each substance in an excipient as either an acceptable part of the excipient composition, or an impurity, is very challenging. As part of USP’s Up-to-Date initiative, USP is making progress in working towards updating excipient monographs to include modern analytical techniques that help reveal excipient composition. It also sheds new light on the variability in composition of many excipients. Consequently, it becomes more critical to have clear guidelines for setting specifications for excipients, to provide consistent practice, and to reduce the time it takes to obtain information to set these specifications.
Results: Therefore, it is important to recognize the potential impact of excipients on product formulations and understand that any changes to the excipient specifications could have unintended consequences on effectiveness of drug products or impact the availability of materials needed to manufacture products.
Conclusion: The poster will provide the views of the USP Excipient Impurities Joint Subcommittee on the complexity of excipient composition, describe challenges that the Excipient Monographs 1 and 2 Expert Committees face in setting specifications for different components and impurities in excipients, provide a proposed direction and guidance in standards setting and establishing specifications for excipient components and impurities.
Catherine Sheehan– Senior Director, United States Pharmacopeia (USP), Rockville, Maryland