The oral, selective phosphodiesterase type-4 inhibitor roflumilast reduces exacerbations and improves lung function in patients with severe-to-very severe chronic obstructive pulmonary disease (COPD). We investigated the efficacy and safety of roflumilast used concomitantly with long-acting β(2)-agonists (LABAs) to reduce exacerbations, and the influence of exacerbation history. Pooled data were analysed from two 12-month, placebo-controlled roflumilast (500 μg once daily) studies involving 3,091 patients with severe-to-very severe COPD. Approximately half of patients used concomitant LABAs; 39% used concomitant short-acting muscarinic antagonists (SAMAs); 27% were frequent exacerbators (two or more exacerbations per year). Roflumilast reduced the rate of moderate or severe exacerbations, with LABA (rate ratio (RR) 0.79, 95% CI 0.69-0.91; p=0.001) or without LABA (RR 0.85, 95% CI 0.74-0.99; p=0.039) and prolonged time both to first (p=0.035 with LABA, p=0.300 without LABA) and second (p=0.018 with LABA, p=0.049 without LABA) exacerbations. Frequent exacerbators experienced a reduction in moderate or severe exacerbations (RR 0.78, 95% CI 0.66-0.91; p=0.002). Similarly, roflumilast remained effective with concomitant SAMA. No differences arose in adverse events between these subgroups. Roflumilast may be used to reduce exacerbations and improve dyspnoea and lung function, without increasing adverse events in COPD patients receiving concomitant LABAs.