Evaluating the Impact of Single Dose Tiotropium on Allergen-induced Early Asthmatic Response

What this study is about

Evaluate single dose (2 x 2.5mcg/puff; total dose 5mcg) effect of tiotropium administered 30 minutes prior to allergen challenge on allergen-induced EAR assessed as the maximal % fall in FEV1 after allergen inhalation compared to that of single dose (two puffs) matched placebo administered 30 minutes prior to allergen challenge.

Who can join (things the study team will check)

✅ You may be able to join if…

• age (years) at least 18 years
• no confounding health issue (i.e. no health conditions, other than asthma, that would put the participant at risk or affect data integrity as determined by the principal investigator)
• baseline FEV1 ≥ 65% of predicted normal at Visit 1
• evidence of atopy to an allergen suitable for inhalation challenge following skin prick testing such as house dust mite, grass, cat or horse
• fall in FEV1 of ≥ 20% at a dose of methacholine ≤ 600mcg (methacholine PD20) at Visit 1
• positive response to allergen inhalation challenge (fall in FEV1 of ≥ 15% after inhalation of allergen at a dilution 1:32 or more dillute.
• absence of respiratory infection for at least 4 weeks prior to Visit 1
• absence of significant worsening of asthma that requires health care intervention or prolonged change in medication due to allergen exposure (or other trigger) for at least 4 weeks prior to Visit 1
• women of child-bearing potential shall not be pregnant or lactating
• non-smoker (cigarettes, vaping); ex-smoker with <10 pack year history allowed; cannabis use will be evaluated on a case-by-case basis
• if on as needed budesonide/formoterol therapy, no reported use within 3 weeks prior to allergen challenge

🚫 You may not be able to join if…

• Smoker >10 pack year history

Where this trial is running

• University of Saskatchewan, Saskatoon, Saskatchewan, Canada