Understanding pressurized metered dose inhaler performance

Abstract

Introduction: Deepening the current understanding of the factors governing the performance of the pressurized metered dose inhaler (pMDI) has the potential to benefit patients by providing improved drugs for current indications as well as by enabling new areas of therapy. Although a great deal of work has been conducted to this end, our knowledge of the physical mechanisms that drive pMDI performance remains incomplete.

Areas covered: This review focuses on research into the influence of device and formulation variables on pMDI performance metrics. Literature in the areas of dose metering, atomization and aerosol evolution and deposition is covered, with an emphasis on studies of a more fundamental nature. Simple models which may be of use to those developing pMDI products are summarized.

Expert opinion: Although researchers have had good success utilizing an empirically developed knowledge base to predict pMDI performance, such knowledge may not be applicable when pursuing innovations in device or formulation technology. Developing a better understanding of the underlying mechanisms is a worthwhile investment for those working to enable the next generation of pMDI products.

Keywords:

• aerosols
• atomization
• dose metering
• drug deposition
• pressurized metered dose inhaler
• pulmonary drug delivery

Declaration of interest

This work was partially supported by Natural Sciences and Engineering Research Council of Canada. JW Ivey and WH Finlay have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents, received or pending, or royalties. R Vehring serves as a consultant to Pearl Therapeutics, Inc. and has no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Notes

This box summarizes key points contained in the article.