Background: Breathlessness and exercise intolerance frequently impact the daily life of patients with COPD.
Methods: This double-blind, multicentre, three-period crossover study randomised 111 patients with COPD (mean age 64 years, mean FEV(1) 38% of predicted normal) to budesonide/formoterol 320/9 microg, formoterol 9 microg or placebo, twice daily for 1 week, following a 1-week run-in period with 1-week wash-out between treatments. Terbutaline (0.5 mg/dose) was used as needed. The primary efficacy variable was exercise endurance time (EET) at 75% peak work capacity with cycle ergometry assessed 1 h post-morning dose.
Results: Budesonide/formoterol prolonged EET 1 h post-morning dose versus formoterol by 69 s (P < 0.005) and placebo by 105 s (P < 0.0001) and improved inspiratory capacity (IC) at isotime during exercise versus formoterol by 8% (P = 0.011) and placebo by 16% (P < 0.0001). Borg score at isotime was reduced by 0.48 (P = 0.12) and 0.78 (P = 0.014) compared with formoterol and placebo, respectively. At the repeated cycle test 6 h after morning dose, the effect on EET still favoured budesonide/formoterol over formoterol and placebo, while the isotime IC and Borg score were similar but better than placebo for the active study drugs. Budesonide/formoterol and formoterol improved health status (St George's Respiratory Questionnaire total score: mean difference versus placebo -2.4 and -2.2, respectively). All treatments were well tolerated.
Conclusions: Budesonide/formoterol resulted in a significant improvement in endurance time 1 h after the last morning dose in a 1-week treatment period versus formoterol and placebo. This study demonstrates, for the first time, the benefit of inhaled corticosteroids in addition to long-acting beta(2)-agonists on exercise tolerance in COPD patients. www.clinicaltrials.gov registration number: NCT00489853.