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A lack of novel excipients is threatening the ability of drug developers to translate progress with small molecules and biologics into therapeutic success. The FDA could soon test a new model of excipient review to foster formulation innovation.
Excipients, the ‘inactive’ substances that are mixed with active pharmaceutical ingredients to achieve drug formulation requirements, don’t get much love. But with innovations in medicinal chemistry and biologic discovery redefining what drug developers need in drug formulations, it is time they did. Not only are existing excipients increasingly struggling to keep up, but regulatory hurdles have long been slowing the expansion of the excipient toolbox. An FDA pilot programme to facilitate the review of novel excipients could help the field keep pace.