: Japanese guidelines recommend the addition of a long-acting muscarinic antagonist for patients with asthma uncontrolled on inhaled corticosteroid/long-acting β-agonist (ICS/LABA) therapy, the effectiveness of which is evaluated here. : Retrospective, observational, single-arm cohort study in patients with asthma initiating fluticasone furoate/umeclidinium/vilanterol (FF/UMEC/VI) following ICS/LABA, using independently analyzed data from Japanese claims databases: JMDC and Medical Data Vision (MDV). The index date was that of the first FF/UMEC/VI prescription. Outcomes were assessed during a 12-month follow-up versus a 12-month pre-index period (baseline) and included asthma exacerbations, oral corticosteroid (OCS) use, and short-acting β-agonist (SABA) use. P-values associated with rate ratios (RRs) were estimated using Conditional Poisson regression. : Overall, 3229 patients in the JMDC database and 1135 in the MDV database were included. Following FF/UMEC/VI initiation, the total annualized moderate-severe asthma exacerbation rate in the JMDC database reduced from 0.50 to 0.40 per-person-per-year (PPPY) (RR [95% confidence interval]: 0.78 [0.73, 0.84]; < 0.001), with similar reductions in the MDV database: 0.53 to 0.42 PPPY (0.79 [0.70, 0.89]; < 0.001). In both databases, there was a 20% reduction (JMDC: 0.80 [0.73, 0.88]; < 0.001; MDV: 0.80 [0.68, 0.94]; = 0.005) in patients with ≥1 OCS prescription after FF/UMEC/VI initiation. The proportion of patients with ≥1 SABA canister prescription dropped by 31% 0.69 [0.57, 0.84]; < 0.001) in the JMDC database and 23% (0.77 [0.66, 0.90]; < 0.001) in the MDV database. : This suggests FF/UMEC/VI is effective in improving asthma exacerbations and reducing OCS and SABA use in Japanese patients previously using ICS/LABA in real-world clinical practice.