Tiotropium/olodaterol versus tiotropium in Japanese patients with COPD: results from the DYNAGITO study

Background: The DYNAGITO study was a Phase IIIb, randomized, double-blind, multicenter, active-controlled, parallel-group, 52-week study designed to determine the efficacy and safety of tiotropium and olodaterol combination therapy (TIO+OLO 5/5 mu g) versus tiotropium monotherapy (TIO 5 mu g) for reducing moderate-to-severe exacerbations of COPD. This is a prespecified analysis of the DYNAGITO data in Japanese patients. Patients and methods: Enrolled patients had a diagnosis of COPD with at least one moderate-to-severe exacerbation in the previous 12 months. Of the total 7,880 treated patients in the DYNAGITO study, 461 (TIO+OLO 5/5 mu g: n=226, TIO 5 mu g: n=235) were Japanese. The primary endpoint was the annualized rate of moderate-to-severe COPD exacerbations. The key secondary endpoint was the time to first moderate-to-severe COPD exacerbation, and other secondary endpoints included the annualized rate of exacerbations leading to hospitalization, time to first COPD exacerbation leading to hospitalization, and all-cause mortality. Safety data were analyzed descriptively. Results: Combination therapy with TIO+OLO resulted in a 29% lower rate of moderate-to-severe COPD exacerbations relative to TIO monotherapy (rate ratio 0.71; 99% CI: 0.46, 1.10; p=0.0434). The risk of a first moderate-to-severe COPD exacerbation was 19% lower with TIO+OLO combination therapy than with TIO monotherapy (HR 0.81; 99% CI: 0.57, 1.17; p=0.1379), although this difference was not statistically significant. The annualized rate of COPD exacerbations requiring hospitalization was 14% lower in the TIO+OLO arm than in the TIO arm (rate ratio 0.86; 95% CI: 0.52, 1.42; p=0.5654). The adverse event incidence was balanced between treatment arms. Conclusion: In a prespecified subgroup analysis of Japanese patients in the DYNAGITO study, combination therapy with TIO+OLO was more effective than TIO in reducing exacerbations. Both treatments were well tolerated.