IPEC Publishes Version 3 of the Excipient Composition Guide

The International Pharmaceutical Excipients Council (IPEC) published the third version of its Excipient Composition Guide for Pharmaceutical Excipients. The guide provides voluntary best-practice guidance to help manufacturers establish excipient composition profiles and communicate relevant information to users and regulators. First published in 2009, the guide was revised in 2020 as Version 2 and has now been updated again.

An excipient may contain more than the nominal component indicated by its name. Depending on the starting materials and manufacturing process, it may also contain concomitant components, impurities, degradants, additives, processing aids or their residuals, and unreacted starting materials. A systematic understanding of these components and their potential variability can help pharmaceutical companies account for excipients appropriately during pharmaceutical development.

Relevance to QbD and supply-chain collaboration

The guide supports the incorporation of excipients and their variability into Quality-by-Design (QbD) development programmes. Composition profiles may help to:

• assess excipient quality and batch-to-batch consistency;
• evaluate, using a risk-based approach, the potential impact of variable components on product quality and patient safety;
• support manufacturing process monitoring, change control and the establishment of product specifications; and
• facilitate structured information exchange between excipient manufacturers, pharmaceutical users and regulators.

The guide is explicitly intended as voluntary guidance, not as a regulatory requirement. It does not replace applicable national or regional regulations or the case-by-case assessment of a specific excipient and its intended use.

What has changed since Version 2?

IPEC highlights the following key enhancements in Version 3:

• Biotech- and fermentation-derived excipients: These excipients are now specifically addressed. The guide discusses, among other topics, potential process residuals and variability associated with biological sources.
• Revised characterization section: Section 4.1, covering types of components and the physicochemical characterization of excipients, has been updated and reorganized. Categories such as concomitant components, reaction by-products, impurities, additives and processing aids are addressed in greater detail.
• Expanded glossary: Terms and definitions for different types of excipient components have been added or expanded.
• Example composition profile: A sample report in the annex illustrates how a composition profile report can be structured and how components may be presented according to information or confidence tiers.
• Editorial harmonization: Terminology and explanations have been revised, and redundancies have been reduced throughout the guide.

Practical implications

The updated edition may be particularly relevant to excipient manufacturers establishing or revising composition profiles, and to pharmaceutical companies assessing excipient variability in development, quality evaluation and regulatory documentation. The guide also emphasizes risk-based assessment and appropriate communication between suppliers and users. Confidential or commercially sensitive information should be protected; suitable confidentiality agreements may be used where information needs to be exchanged.

Version 3 of the IPEC Excipient Composition Guide is available after registration on the IPEC website.