Today (12 April 2023) USFDA's Center for Drug Evaluation and Research released two draft guidances on"Assessing Adhesion With Transdermal and Topical Delivery Systems for ANDAs" and "Assessing the Irritation and Sensitization Potential of Transdermal and Topical Delivery Systems for ANDAs".
Transdermal delivery systems (TDDS) are drug delivery systems that deliver drugs through the skin and into the bloodstream.
Topical delivery systems, on the other hand, are drug delivery systems that deliver drugs to the site of action on the skin or mucous membranes.
This revised draft guidance provides recommendations for evaluating the adhesion performance of transdermal or topical delivery systems (referred to collectively as TDS).
According to the objectives of a generic TDS product development program, applicants may choose either to evaluate TDS adhesion through studies that only evaluate TDS adhesion or to studies that evaluate TDS adhesion in conjunction with pharmacokinetic (PK) endpoints (for example, for evaluating both adhesion and bioequivalence at the same time).
The proposed revised draft guidance provides recommendations for the design and conduct of studies that will determine whether a transdermal or topical delivery system (collectively known as TDS) is likely to cause irritation (I) or sensitization (S) of the (I/S) skin and also Clarifies when an in vivo study to assess the sensitization potential of a TDS product may not be needed.