Improved airway targeting with the CFC-free HFA-beclomethasone metered-dose inhaler compared with CFC-beclomethasone.

Abstract

Hydrofluoroalkane-134a (HFA) beclomethasone dipropionate (BDP) was formulated in a metered-dose inhaler (MDI) to deliver a particle size of 1.1 microm compared with 35 microns for currently marketed chlorofluorocarbon (CFC)-BDP products. Two phase I single-dose human deposition studies were conducted using technetium 99m-radiolabelled BDP in a press-and-breathe actuator without an add-on spacer. A healthy volunteer study (n=6) showed that 55-60% of the HFA-BDP ex-actuator dose was deposited in the lungs, with 29-30% deposited in the oropharynx. CFC-BDP deposition was 4-7% in the lungs and 90-94% in the oropharynx. The pattern of deposition within the lung showed that HFA-BDP was spread diffusely throughout the lung airways, whereas CFC-BDP was confined to the central airways with little, if any, peripheral airway deposition. A second study with asthmatics (n=16) confirmed that 56% of the HFA-BDP dose was deposited in the airways, with 33% in the oropharynx. In conclusion, hydrofluoroalkane-134a-beclomethasone dipropionate deposition was much greater in the airways than chlorofluorocarbon-beclomethasone dipropionate, with a concomitant reduction in oropharyngeal deposition. The increased lung deposition efficiency of the hydrofluoroalkane propellant has led to a reduction in the amount of beclomethasone dipropionate needed to achieve a similar efficacy. The penetration of the hydrofluoroalkane to the small airways may provide asthma treatment not afforded by conventional chlorofluorocarbons.

• Authors: C L Leach, P J Davidson, R J Boudreau
• Journal: The European respiratory journal (Eur Respir J) Vol. 12 Issue 6 Pg. 1346-53 (Dec 1998) ISSN: 0903-1936 [Print] England
• PMID: 9877489 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Aerosol Propellants
• Chlorofluorocarbons
• Glucocorticoids
• Hydrocarbons, Fluorinated
• Betamethasone
• apaflurane

Topics

• Adolescent
• Adult
• Aerosol Propellants
• Asthma (drug therapy, metabolism)
• Betamethasone (administration & dosage, pharmacokinetics)
• Chlorofluorocarbons
• Female
• Glucocorticoids (administration & dosage, pharmacokinetics)
• Humans
• Hydrocarbons, Fluorinated
• Lung (metabolism)
• Male
• Middle Aged
• Nebulizers and Vaporizers
• Oropharynx (metabolism)