Efficacy and Safety of Flutiform K-haler in Patients With Uncontrolled Asthma Following Mid-dose ICS/LABA DPI Therapy

Asthma is a chronic inflammatory allergic disease of airway involving many cells and various media. Airway inflammation causes various symptoms of airway hypersensitivity, including repeated wheezing, dyspnea, and tightness in the chest. An estimated 300 million people worldwide suffer from asthma, and in South Korea, an estimated asthma prevalence rate for adults is approximately 5% \[1\]. For more effective management of asthma, Global Initiative for Asthma (GINA) guideline\[2\] and Korean Asthma Management Guideline for Adults \[1\] suggests that for patients who cannot have asthma symptoms under control with ICS (Inhaled Corticosteroid) alone, concomitant treatment of ICS/LABA is more effective than dose increase of ICS, and therefore recommends ICS combined with Long-acting β2-agonist (LABA) products. Common ICS/LABA products that are available in the Korea market including dry power inhaler (DPI) and pressured metered dose inhaler (pMDI). It is known that small airway significantly contributes to total airway resistance, so the inflammation of the small airways could lead to the poor asthma control observed since small airways are not directly reached by inhaler's particles \[3,4\]. Fluticasone/formoterol (Flutiform®) shows a high fine particle fraction (FPF) of about 40% for both the ICS and the LABA components regardless the inhalation flow rate\[5\]. FPF of Fluticasone/formoterol is significantly higher than other ICS/LABA combinations. It is expected that small particles of fluticason/formoterol could reach to the large/small airways easier than other ICS/LABA combinations even if these ICS/LABAs shows a similar efficacy for asthma treatment. However Asthma patients can struggle to use their pMDI inhalers correctly due to the need to properly co-ordinate the press and inhale, which can worsen their asthma and lead to exacerbations. Flutiform K-haler is the first breath-actuated inhaled corticosteroid (ICS) long-acting β2-agonist (LABA) combination aerosol inhaler for adults and adolescents. The flutiform k-haler has been designed with patients in mind, requiring only a gentle inhalation to trigger the dose release, with the aim to help patients reduce critical errors and improve long-term outcomes. Therefore, It is expected that Flutiform K-haler prevents exacerbation and improves symptom of Asthma. Especially it will be beneficial to patients who did not response to existing ICS/LABA DPI in Korea. This study is planned to examine the efficacy and safety of Flutiform K-haler in patients who are not adequately controlled by previous mid-dose ICS/LABA DPI treatment.