Foster®: A High-Efficiency Combination Metered Dose Inhaler with Consistent Particle Size Distribution at Alternative Flow RatesReport as inadecuate

Foster®: A High-Efficiency Combination Metered Dose Inhaler with Consistent Particle Size Distribution at Alternative Flow Rates - Download this document for free, or read online. Document in PDF available to download.

Combination Products in Therapy

, Volume 4, Issue 1–2, pp 1–5

First Online: 03 January 2014Received: 08 November 2013DOI: 10.1007-s13556-013-0006-6

Cite this article as: De Maria, R., Zagnoni, I., Bodria, A. et al. Comb Prod Ther 2014 4: 1. doi:10.1007-s13556-013-0006-6


IntroductionThis publication adds perspective to a recent publication by Johal et al. that presented the performance of combination inhalation therapies at a flow rate differing from that recommended by the regulatory authorities for metered dose inhaler MDI performance testing. Altering the flow rate through an impactor can create potential pitfalls which can result in performance misrepresentation.

Performance Testing of MDIs at Non-Standard Flow RatesIn-house data for Foster Chiesi, Parma, Italy and Flutiform Bard Pharmaceuticals Limited, Cambridge, UK have been collected using standard pharmacopaeial conditions and also at the unconventional 60 L-min flow rate utilized by Johal et al. A marked reduction in mass median aerodynamic diameters MMADs of both the inhaled corticosteroids ICS and long-acting beta agonists in Foster MDI from approximately 1.2–0.5 μm with increase in flow rate Johal et al. is not observed. Use of the Andersen cascade impactor at flow rates above 28.3 L-min is not common practice. The industry generally utilizes data from the next generation impactor NGI, an impactor specifically designed and developed for this purpose. Data for the ICS component of Foster have been generated using an NGI operated at 30 and 60 L-min, yielding an MMAD ±SD of 1.1 ± 0.1 μm at both flow rates.

Therapeutic Significance of Submicron ParticlesJohal et al. suggest that submicron particles are prone to be exhaled by the patient, and therefore imply that they may be non-effective. However, therapeutic significance of submicron particles is supported by a scintigraphic lung deposition study carried out using the Foster MDI. The in vivo data highlight that just 2–3% of the nominal dose was exhaled, with 31–34% deposited in the lungs.

ConclusionConsistent particle size distribution of both active drug components delivered from Foster MDI at flow rates of 28–30 and 60 L-min is observed.

KeywordsMetered dose inhaler Particle size distribution Andersen cascade impactor Next generation impactor Sampling flow rate Foster Flutiform Electronic supplementary materialThe online version of this article doi:10.1007-s13556-013-0006-6 contains supplementary material, which is available to authorized users.

Download fulltext PDF

Author: Roberta De Maria - Ingrid Zagnoni - Alessandro Bodria - Sauro Bonelli - Massimiliano Dagli Alberi - David Andrew Lewis -


Related documents