Background: The study evaluated the efficacy of beclomethasone dipropionate/formoterol fumarate (BDP/FF) extrafine combination versus fluticasone propionate/salmeterol (FP/S) combination in COPD patients. Methods: The trial was a 12-week multicentre, randomised, double-blind, double dummy study; 419 patients with moderate/severe COPD were randomised to BDP/FF 200/12 mu g or FP/S 500/50 mu g twice daily. The primary objective was to demonstrate the equivalence between treatments in terms of Transition Dyspnoea Index (TDI) score and the superiority of BDP/FF in terms of change from pre- dose in the first 30 minutes in forced expiratory volume in the first second (FEV1). Secondary endpoints included lung function, symptom scores, symptom-free days and use of rescue medication, St. George's Respiratory Questionnaire, six minute walking test and COPD exacerbations. Results: BDP/FF was equivalent to FP/S in terms of TDI score and superior in terms of FEV1 change from pre- dose (p <0.001). There were no significant differences between treatments in secondary outcome measures, confirming overall comparability in terms of efficacy and tolerability. Moreover, a clinically relevant improvement (> 4 units) in SGRQ was detected in the BDP/FF group only. Conclusion: BDP/FF extrafine combination provides COPD patients with an equivalent improvement of dyspnoea and a faster bronchodilation in comparison to FP/S.