title: Transdermal drug delivery system (TDDS) adhesion as a critical safety, efficacy and quality attribute.
abstract: Transdermal drug delivery systems (TDDS), also known as "patches," are dosage forms designed to deliver a therapeutically effective amount of drug across a patient's skin. The adhesive of the transdermal drug delivery system is critical to the safety, efficacy and quality of the product. In the Drug Quality Reporting System (DQRS), the United States Food and Drug Administration (FDA) has received numerous reports of "adhesion lacking" for transdermal drug delivery systems. This article provides an overview of types of transdermals, their anatomy, the role of adhesion, the possible adhesion failure modes and how adhesion can be measured. Excerpts from FDA reports on the lack of adhesion of transdermal system products are presented. Pros and cons of in vitro techniques, such as peel adhesion, tack and shear strength, in vivo techniques used to evaluate adhesive properties are discussed. To see a decrease in "adhesion lacking" reports, adhesion needs to become an important design parameter and suitable methods need to be available to assess quality and in vivo performance. This article provides a framework for further discussion and scientific work to improve transdermal adhesive performance.
authors.affiliation: Food and Drug Administration, Division of Pharmaceutical Analysis, St. Louis, MO 63101, USA. anna.wokovich@fda.hhs.gov
authors.forename: Anna M
authors.initials: AM
authors.lastname: Wokovich
authors.forename: Suneela
authors.initials: S
authors.lastname: Prodduturi
authors.forename: William H
authors.initials: WH
authors.lastname: Doub
authors.forename: Ajaz S
authors.initials: AS
authors.lastname: Hussain
authors.forename: Lucinda F
authors.initials: LF
authors.lastname: Buhse
mesh_terms: D000279:Administration, Cutaneous; D016907:Adverse Drug Reaction Reporting Systems; D002626:Chemistry, Pharmaceutical; D003692:Delayed-Action Preparations; D016503:Drug Delivery Systems / Q000379:methods*; D006801:Humans; D004364:Pharmaceutical Preparations; D011786:Quality Control; D012449:Safety; D012869:Skin Absorption; D013678:Technology, Pharmaceutical / Q000379:methods*; D014481:United States
chemical_list: D003692:Delayed-Action Preparations; D004364:Pharmaceutical Preparations