Excipients serve a critical role in the production of final dosage forms for drug products and biologics. They facilitate the manufacturing process (e.g., anticaking agents) and protect, support, and enhance stability. They may also improve bioavailability. In addition, excipients help maintain the safety, or function, of the product during storage and use.

No longer characterized as inert accompaniments to an active pharmaceutical ingredient (API), excipients are the target of an intensified push for more stringent quality management, placing new requirements on both suppliers and users. Regulating excipient quality, however, is no small task. The global market is expected to exceed $5 billion by 2020—with a growth rate of 6.0% from 2014 to 2020 (1). Thousands of different excipients are available, and only a small percentage of them are manufactured solely for pharmaceutical use.

For many years, there have been clearly defined GMP requirements for APIs, including EU GMP Part II, 21 CFR Part 11 and ICH Q7: Good Manufacturing Practice for Active Pharmaceutical Ingredients. But, until recently, well-defined and stringent GMP requirements for excipients did not exist.