Background and objective: Large clinical trials have confirmed the long-term efficacy of inhaled corticosteroid/long-acting beta(2)-agonist combinations in patients with chronic obstructive pulmonary disease (COPD). It was hypothesized that significant treatment effects would already be present within 3 months after the initiation of treatment across a range of clinical outcomes, irrespective of COPD severity.

Methods: Post hoc analysis of 3-month post-randomization outcomes, including exacerbation rates, dropouts, symptoms, reliever use, and lung function, from three studies with similar inclusion criteria of moderate-to-very-severe COPD. Patients (n=1,571) were treated with budesonide/formoterol (B/F) 320/9 mu g or placebo, twice daily; in one study, tiotropium 18 mu g once daily was also given.

Results: Over the first 3 months of treatment, fewer patients randomized to B/F experienced exacerbations versus the placebo group (111 and 196 patients with >= 1 exacerbation, respectively). This was true in each COPD severity group. Compared with placebo, B/F treatment led to significantly lower 3-month exacerbation rates in the moderate and severe COPD severity groups (46% and 57% reduction, respectively), with a nonsignificant reduction (29%) in very severe COPD. Fewer dropouts occurred among patients treated with B/F versus placebo, this effect being greater with increasing COPD severity. B/F was associated with improved forced expiratory volume in 1 s, morning peak expiratory flow rate, total reliever use, and total symptom score versus placebo.

Conclusion: Treatment with B/F decreased exacerbations in patients with moderate-to-very-severe COPD within 3 months of commencing treatment. This effect was paralleled by improved lung function, less reliever medication use, and fewer symptoms, irrespective of disease severity.