Excipients: New opportunities for complex challenges - USP's approaches

The quality of excipients is important since they can make up to about 90% of the total mass/volume of the drug product. Traditionally, excipients specifications were established with a focus on quality for intended use in the drug product and less on excipient composition, and physical and chemical properties, however, the increasing demand for high quality excipients used in the development of nanomedicines and novel delivery systems requires higher quality and purity, e.g., use of phospholipids in development of Covid-19 vaccine nanomedicine delivery systems. USP is collaborating with stakeholders to address the lack of standardized test methods for complex/polymeric type excipients (e.g., phospholipids/LG polymers) offering new solutions and help with excipient compositional and variability issues along with associated environmental aspects. By expanding its offerings through its "emerging standards" new model for stakeholder engagement, USP is more flexible in its solutions offerings that favor earlier interaction in the genesis of quality standards in a more iterative way. This publication will provide an overview of evolving compendial approaches (e.g., standalone chapters) and expanded solutions and offerings (use of analytical reference materials (ARMS), associated application (App) notes, and technical guides).