Excipient Excitement

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Two years is a long time for an emergency. The US Food and Drug Administration and other regulatory bodies have given tremendous support and guidance for emergency use authorization whilst maintaining background duties such as inspections and evaluations. However, a majority of APIs now under development are considered poorly soluble and/or poorly permeable. Therefore, hard questions are currently being asked of formulators to develop new solutions. Lipid-based drug delivery is one of those answers. Immediately this causes another set of questions regarding both excipients and adjuvants. Some fingers at the recent the PharmSci 360 American Association of Pharmaceutical Scientists Philadelphia conference pointed tentatively toward polyethylene glycol (PEG) as being a problematic adjuvant. More questions are bound to follow. Although new to vaccine applications, PEG is commonly used in many other formulations. It has been linked to rare instances of shortness of breath, low blood pressure, rash, and highly elevated heart rates. Despite some scientists pointing out prior exposure to PEG can create high levels of antibodies against PEG (putting these people at some small risk of an anaphylactic reaction), it was clearly the most effective choice given all conditions and considerations.

That choice does now throw light upon the last largely static decade of excipient and adjuvant advances. Proposals are now being accepted for a Novel Excipient Review Pilot programme at FDA. Universally welcomed, the pilot also carries a burden of very high expectations for being enlarged. In a recent interview with Pharmaceutical Technology Europe, Nigel Langley, global technology director at BASF Corporation Pharma Solutions stated a view widely held within the industry, “I am personally very excited and supportive of the FDA Novel Excipient Pilot Review Programme as I believe this will encourage innovation in developing and introducing new excipients specifically designed to help meet current and future drug formulation challenges. These unmet formulation needs are relevant for both small molecule and biologic drugs, for example, in poorly soluble drugs and in enhancing the stability of protein based therapeutics. I am hopeful that the pilot programme will be successful and a formal programme will follow, one that will consider all types of novel excipients in the future, including co-processed excipients and excipients used for different routes of administration.”


While COVID-19 caused a metaphorical ‘stress test’ for our industry, the focus it placed on certain pivotal sections of both the development and also manufacturing supply chain, will hopefully yield future benefits.