The additive effects of Pranlukast in stable asthmatic patients with the regular use of FP/LABA combination drug –(1) Open-label, randomized and comparative study–

INTERVENTION: Treatments with FP/LABA combination drug and Pranlukast for 4 weeks. Treatments with FP/LABA combination drug for 4 weeks. CONDITION: Asthma PRIMARY OUTCOME: Peripheral airway inflammation in induced sputum (Eosinophils and ECP) SECONDARY OUTCOME: 1.Asthmatic symptoms and QOL(AQLQ); 2.Pulmonary functions (PEF, FEV1, FEF50,FEF75); 3.Eosinophils in peripheral blood INCLUSION CRITERIA: 1.Patients with FP/LABA combination drug more than 3 months 2.Stable asthmatic patients who evaluate themselves to be well‐controlled or better