title: A valved holding chamber does not decrease the bronchodilator activity of budesonide-formoterol combination metered dose inhaler.
abstract: OBJECTIVE
  Spacers and valved holding chambers (VHCs) were developed to facilitate using pressurized metered dose inhaler (pMDI) by patients who could not coordinate the actions required for successful pMDI use. There is little in vivo evidence about how VHC may affect the bronchodilation from combination drugs in pMDI. This study was to determine the effect, if any, of VHC on the bronchodilating actions of the pMDI budesonide/formoterol combination.
  
  
  METHODS
  Sixteen adult asthmatic subjects with 15% or greater reversibility of forced expiratory volume in one second (FEV-1), 15 minutes after inhaling 180-360 μg of albuterol, participated. The study had a randomized crossover design with each subject using budesonide-formoterol pMDI as described in the product information one timeand on a second occasion using the pMDI with a VHC. Spirometry and impedance osscilometry were measured at baseline and repeatedly over a 12-hour period. This study was approved by IntegReview Institutional Review Board, Austin, TX, USA. The clinical trial number for this study was NCT 009-15538 (http://www.westernskymed.com).
  
  
  RESULTS
  The area under the curve of FEV-1, the FEV-1, and the fraction FEV-1/FVC was similar over the 12-hour time frame with both methods. Resistance was not different at any time point. In both procedures, the onset of bronchodilation occurred rapidly within 3 to 5 minutes.
  
  
  CONCLUSIONS
  In well-trained asthmatic subjects, both tested methods caused equivalent bronchodilation. This suggests a VHC itself has no deleterious effect on the bronchodilator activity in the combined drug. These results may not apply to patients who have coordination problems with the pMDI and further study is indicated.
authors.affiliation: Western Sky Medical Research, El Paso, TX 79903, USA. immunman@westernskymed.com
authors.forename: Lyndon E
authors.initials: LE
authors.lastname: Mansfield
authors.forename: Ruby
authors.initials: R
authors.lastname: Maynes
mesh_terms: D000280:Administration, Inhalation; D000305:Adrenal Cortex Hormones / Q000008:administration & dosage*; D000328:Adult; D018927:Anti-Asthmatic Agents / Q000008:administration & dosage*; D001249:Asthma / Q000188:drug therapy*; D019819:Budesonide / Q000008:administration & dosage*; D000069502:Budesonide, Formoterol Fumarate Drug Combination; D018592:Cross-Over Studies; D004338:Drug Combinations; D004983:Ethanolamines / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D036503:Inhalation Spacers; D008297:Male; D036501:Metered Dose Inhalers; D008875:Middle Aged; D013147:Spirometry
chemical_list: D000305:Adrenal Cortex Hormones; D018927:Anti-Asthmatic Agents; D000069502:Budesonide, Formoterol Fumarate Drug Combination; D004338:Drug Combinations; D004983:Ethanolamines; D019819:Budesonide