USA – Residual Drug in Transdermal and Related Drug Delivery Systems

This guidance provides recommendations to developers and manufacturers of transdermal drug delivery systems (TDDS), transmucosal drug delivery systems (TMDS), and topical patch products regarding use of an appropriate scientific approach during product design and development—as well as during manufacturing and product lifecycle management—to ensure that the amount of residual drug substance at the end of the labeled use period is minimized…