title: Dry powder inhalation: past, present and future.
abstract: Early dry powder inhalers (DPIs) were designed for low drug doses in asthma and COPD therapy. Nearly all concepts contained carrier-based formulations and lacked efficient dispersion principles. Therefore, particle engineering and powder processing are increasingly applied to achieve acceptable lung deposition with these poorly designed inhalers. Areas covered: The consequences of the choices made for early DPI development with respect of efficacy, production costs and safety and the tremendous amount of energy put into understanding and controlling the dispersion performance of adhesive mixtures are discussed. Also newly developed particle manufacturing and powder formulation processes are presented as well as the challenges, objectives, and new tools available for future DPI design. Expert opinion: Improved inhaler design is desired to make DPIs for future applications cost-effective and safe. With an increasing interest in high dose drug delivery, vaccination and systemic delivery via the lungs, innovative formulation technologies alone may not be sufficient. Safety is served by increasing patient adherence to the therapy, minimizing the use of unnecessary excipients and designing simple and self-intuitive inhalers, which give good feedback to the patient about the inhalation maneuver. For some applications, like vaccination and delivery of hygroscopic formulations, disposable inhalers may be preferred.
authors.affiliation: a Department of Pharmaceutical Technology and Biopharmacy , University of Groningen , Groningen , The Netherlands.
authors.forename: A H
authors.initials: AH
authors.lastname: de Boer
authors.affiliation: a Department of Pharmaceutical Technology and Biopharmacy , University of Groningen , Groningen , The Netherlands.
authors.forename: P
authors.initials: P
authors.lastname: Hagedoorn
authors.affiliation: a Department of Pharmaceutical Technology and Biopharmacy , University of Groningen , Groningen , The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Hoppentocht
authors.affiliation: b Department of Pharmacy , University of Parma , Parma , Italy.
authors.forename: F
authors.initials: F
authors.lastname: Buttini
authors.affiliation: a Department of Pharmaceutical Technology and Biopharmacy , University of Groningen , Groningen , The Netherlands.
authors.forename: F
authors.initials: F
authors.lastname: Grasmeijer
authors.affiliation: a Department of Pharmaceutical Technology and Biopharmacy , University of Groningen , Groningen , The Netherlands.
authors.forename: H W
authors.initials: HW
authors.lastname: Frijlink
mesh_terms: D000280:Administration, Inhalation; D001249:Asthma / Q000188:drug therapy*; D002626:Chemistry, Pharmaceutical; D016503:Drug Delivery Systems; D058995:Dry Powder Inhalers; D005079:Excipients / Q000737:chemistry; D006801:Humans; D008168:Lung / Q000378:metabolism; D011208:Powders
chemical_list: D005079:Excipients; D011208:Powders
keywords: Adhesive mixtures; drug deposition; drug formulation; dry powder inhaler design; inhalation; particle engineering