- Current Asthma Maintenance Therapy: Outpatients are eligible if they have received ICS+LABA or ICS+LABA＋LAMA with asthma control status as Not well controlled with ICS (mid-dose) +LABA ; Not well controlled with ICS (high-dose) +LABA or Controlled with ICS (mid-dose) +LABA + LAMA; Not well controlled with ICS (mid-dose) +LABA + LAMA; Controlled with ICS (high-dose) +LABA + LAMA respectively in stable regimen and dosage for at least 4 weeks prior to screening visit (Visit 1) (with medium to high dose of ICS defined by the Japanese Guidelines [JGL]). Asthma Control Questionnaire (ACQ-6) will be used for the assessment of control status of asthma at Visit 1 (screening Visit) (i.e., less than or equal to 0.75 points shows controlled and > 0.75 shows not well controlled).