Evaluation of Rapid Onset of Action of ICS/LABA Combination Therapies on Respiratory Function in Asthma Patients: A Single-Center, Open-Label, Randomized, Crossover Trial

Abstract

Introduction: Products based on inhaled corticosteroid (ICS)/long-acting β2 agonist (LABA) combinations may provide different clinical benefits. This study was conducted to compare the rapid effects of three such combination products: formoterol/fluticasone (FFC) aerosol (pMDI), formoterol/budesonide (FBC) dry powder inhaler (DPI), and vilanterol/fluticasone furoate (VFC) DPI. Methods: The study design was a three-armed, randomized, crossover study. Patients included in the study had stable moderate asthma, defined as an Asthma Control Questionnaire (ACQ) score ≤ 0.75, and were undergoing step 2 or 3 asthma treatment as defined by JGL2015. Subjects were treated with fluticasone propionate inhaled via Diskus® during a 2-week washout period before randomization. At visit 2, subjects were randomly assigned in a 1:1:1 ratio to FFC, FBC, or VFC, and evaluated for changes in pulmonary function over time. At visits 3 and 4, the treatment was switched to another ICS/LABA combination in a crossover manner after a 1-week washout period. Spirometry was performed pre-dose and at 3, 10, and 30 min post-dose, and forced oscillation was implemented pre-dose and at 1, 7, 15, and 60 min post-dose. Results: Fifteen outpatients (63.3 ± 9.5 years, ACQ: 0.13 ± 0.19) completed the study. ∆FEV1 at 3 min did not significantly differ among the three groups. Significant increases in FEV1 and %FEV1 from baseline were observed in the FFC (p = 0.004, 0.003), FBC (p = 0.014, 0.011), and VFC (p = 0.032, 0.023) groups at 30 min. Improvements in respiratory resistance at 5–20 Hz from baseline at 60 min, resonant frequency, respiratory system reactance at 5 Hz, and low-frequency reactance area from baseline were observed at 1 min in the FFC group (p = 0.014, 0.002, 0.027, 0.018, respectively). Conclusion: FFC administered using a pMDI showed favorable delivery to peripheral airways and significantly more rapid action promptly after inhalation as compared with other ICS/LABA preparations inhaled using a DPI, thus broadening the potential therapeutic options for asthma. Trial Registration Number: UMIN000029379. Funding: Kyorin Pharmaceutical Co., Ltd.