title: The potential of polymeric film-forming systems as sustained delivery platforms for topical drugs.
abstract: BACKGROUND
  Dosing regimens requiring multiple daily applications frequently result in poor patient compliance, especially in the treatment of chronic skin diseases. Consequently, development of sustained delivery systems for topical drugs permitting less frequent dosing is of continuing interest for dermatological therapy.
  
  
  METHODS
  This potential of polymeric film-forming systems (FFS), created in situ on the skin, as sustained delivery platforms for topical drug delivery is reviewed. Key formulation parameters that determine delivery efficiency are considered focussing on those that permit a drug reservoir to be established in the upper layers of the skin and/or on the skin surface from which release can be sustained over a prolonged period. The advantageous and superior cosmetic attributes of FFS (compared to conventional semi-solid formulations) that offer significantly improved patient compliance are also addressed.
  
  
  CONCLUSIONS
  The promise of polymeric FFS as convenient and aesthetic platforms for sustained topical drug delivery is clear. Manipulation of the formulation allows the delivery profile to be customized and optimized to take advantage of both a rapid, initial input of drug into the skin (likely due to a transient period of supersaturation) and a slower, controlled release over an extended time from the residual film created thereafter.
authors.affiliation: a LEO Pharma A/S, Pharmaceutical Technologies , Ballerup , Denmark.|b Department of Pharmacy & Pharmacology , University of Bath , Bath , UK.
authors.forename: Kit
authors.initials: K
authors.lastname: Frederiksen
authors.affiliation: b Department of Pharmacy & Pharmacology , University of Bath , Bath , UK.
authors.forename: Richard H
authors.initials: RH
authors.lastname: Guy
authors.affiliation: a LEO Pharma A/S, Pharmaceutical Technologies , Ballerup , Denmark.
authors.forename: Karsten
authors.initials: K
authors.lastname: Petersson
mesh_terms: D002626:Chemistry, Pharmaceutical; D016503:Drug Delivery Systems; D006801:Humans; D004364:Pharmaceutical Preparations / Q000008:administration & dosage*; D011108:Polymers / Q000737:chemistry*; D012867:Skin / Q000378:metabolism
chemical_list: D004364:Pharmaceutical Preparations; D011108:Polymers
keywords: Dermal drug delivery; polymeric film-forming systems; supersaturation; sustained delivery; topical formulations