title: The spirometric efficacy of once-daily dosing with tiotropium in stable COPD: a 13-week multicenter trial. The US Tiotropium Study Group.
abstract: OBJECTIVE
  To compare the bronchodilator efficacy and safety of tiotropium and placebo.
  
  
  METHODS
  A 3-month, randomized, double-blind, placebo-controlled, multicenter trial.
  
  
  METHODS
  Outpatient.
  
  
  METHODS
  Four hundred seventy patients with stable COPD (mean FEV(1) = 38.6% predicted).
  
  
  METHODS
  Tiotropium 18 microg (N = 279) or placebo (N = 191) given once daily via a lactose-based dry-powder inhaler device.
  
  
  RESULTS
  Spirometry was evaluated on days 1, 8, 50, and 92. Data were expressed as the mean trough (ie, before morning dose; 23 to 24 h after previous dose) and average response observed in the 3 h after the dose was received. Tiotropium produced significant improvement in trough FEV(1) and FVC, averaging 12% greater than baseline on day 8; these improvements were maintained on days 50 and 92. The average postdose FEV(1) was 16% greater than baseline on day 1 and 20% greater than baseline on day 92; FVC was 17% greater than baseline on day 1 and 19% greater than baseline on day 92. Tiotropium was significantly more effective than placebo in both trough and average FEV(1) and FVC response (p < 0.001). These spirometric effects were corroborated by significant improvements in daily morning and evening peak expiratory flow rate, as well as a reduction in "as-needed" albuterol use. Symptoms of wheezing and shortness of breath were significantly less in patients receiving tiotropium, and the physician global assessment noted overall improvements with those treated with tiotropium relative to placebo. The most common reported adverse event after tiotropium was dry mouth (9.3% vs 1.6% relative to placebo; p < 0.05).
  
  
  CONCLUSIONS
  These data demonstrate that tiotropium is a safe and effective once-daily anticholinergic bronchodilator and should prove useful as first-line maintenance therapy in COPD.
authors.affiliation: Harbor-UCLA Research and Education Institute (Dr. Casaburi), Torrance, CA 90509, USA. casaburi@ucla.edu
authors.forename: R
authors.initials: R
authors.lastname: Casaburi
authors.forename: D D
authors.initials: DD
authors.lastname: Briggs
authors.forename: J F
authors.initials: JF
authors.lastname: Donohue
authors.forename: C W
authors.initials: CW
authors.lastname: Serby
authors.forename: S S
authors.initials: SS
authors.lastname: Menjoge
authors.forename: T J
authors.initials: TJ
authors.lastname: Witek
mesh_terms: D000368:Aged; D000420:Albuterol / Q000008:administration & dosage / Q000627:therapeutic use; D001993:Bronchodilator Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D018680:Cholinergic Antagonists / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D004311:Double-Blind Method; D004417:Dyspnea / Q000188:drug therapy; D005260:Female; D005500:Follow-Up Studies; D005541:Forced Expiratory Volume / Q000187:drug effects; D006801:Humans; D008168:Lung / Q000187:drug effects*; D008173:Lung Diseases, Obstructive / Q000188:drug therapy*; D008297:Male; D009330:Nebulizers and Vaporizers; D010366:Peak Expiratory Flow Rate / Q000187:drug effects; D010919:Placebos; D012135:Respiratory Sounds / Q000187:drug effects; D012449:Safety; D012602:Scopolamine Derivatives / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D013147:Spirometry; D000069447:Tiotropium Bromide; D014797:Vital Capacity / Q000187:drug effects; D014987:Xerostomia / Q000139:chemically induced
chemical_list: D001993:Bronchodilator Agents; D018680:Cholinergic Antagonists; D010919:Placebos; D012602:Scopolamine Derivatives; D000420:Albuterol; D000069447:Tiotropium Bromide