Evaluating the timing of triple therapy initiation for the treatment of asthma in Japan: prompt versus delayed.

Objective: In Japan, the optimal initiation timing and efficacy of single-inhaler triple therapy (SITT) in asthma management remain unexplored. This study investigated SITT initiation timing following an asthma exacerbation, and examined patient demographics and clinical characteristics.

Methods: Observational, retrospective cohort study in patients with asthma aged ≥15 years who initiated SITT following their earliest observed asthma exacerbation (February-November 2021), using data from Japanese health insurance claims databases (JMDC and Medical Data Vision [MDV]). The study period ended May 2022 for JMDC and September 2022 for MDV. Descriptive analyses were performed independently by database. Variables evaluated included timing of SITT initiation post exacerbation (prompt, delayed and late, ≤30, 31-180 and >180 days post index, respectively), patient demographics, clinical characteristics, and pre-index treatment.

Results: Of patients in the JMDC and MDV databases, most initiated SITT promptly after an asthma exacerbation, 60.8% (n = 951/1565) and 44.4% (n = 241/543), respectively. Delayed initiation occurred in 22.6% (n = 354/1565) and 26.3% (n = 143/543) of patients, and late initiation occurred in 16.6% (n = 260/1565) and 29.3% (n = 159/543), respectively. Most patients were indexed on a moderate asthma-related exacerbation, 97.1% (n = 1519/1565) and 68.7% (n = 373/543), respectively.

Conclusion: Most patients with asthma initiated SITT promptly following a moderate exacerbation, with delayed and late initiation more common among patients with complex clinical profiles. The findings underscore the necessity for future research to examine the interaction between patient characteristics, clinical outcomes, and the timing of SITT initiation to optimize treatment strategies, as clinical practice may vary by exacerbation severity.