Tiotropium superior to salmeterol in preventing exacerbations in COPD

The anticholinergic drug tiotropium is more effective than the β2-agonist salmeterol in preventing exacerbations in patients with moderate-to-very-severe chronic obstructive pulmonary disease (COPD), according to a multicenter European study published in the New England Journal of Medicine.

Researchers compared 18 μg of tiotropium once daily in 3,707 patients with that of 50 μg of salmeterol twice daily in 3,669 patients. Patients had moderate-to-very-severe COPD and a history of exacerbations during the preceding year.

Time to first exacerbation was longer in the tiotropium group than in the salmeterol group (187 days vs 145 days), with a 17% reduction in risk (HR, 0.83). Compared with salmeterol, tiotropium also increased the time to the first severe exacerbation (HR, 0.72), reduced the annual number of moderate or severe exacerbations (0.64 vs 0.72), and reduced the annual number of severe exacerbations (0.09 vs 0.13). The incidence of serious adverse events and adverse events that resulted in discontinuing treatment was similar in both groups. In the tiotropium group there were 64 deaths (1.7%) compared with 78 (2.1%) in the salmeterol group.

"In summary, among patients with moderate-to-very-severe COPD and a history of exacerbation, tiotropium was more effective than salmeterol in all the exacerbation end points that were assessed and across all major subgroups," the authors concluded. "The results of this large trial provide data on which to base the choice of long-acting bronchodilator therapy for maintenance treatment of COPD."