Efficacy of Once-daily Budesonide/Formoterol Turbuhaler 4.5/160 µg in Step Down Asthma

A 12-week, Randomized, Parallel-group, Phase III Study Comparing the Efficacy of Once-daily Budesonide/Formoterol Turbuhaler (160/4.5 μg/d) and Twice-daily Budesonide Giona Easyhaler (400 μg/d) During Step-down Period in Well Controlled Asthma

This study will evaluate the efficacy of Once-daily Budesonide/formoterol Turbuhaler 160/4.5 µg/d in the period of step down in well controlled asthmatic patient.

The study will measure the efficacy of once daily low dose ICS/ LABA in well controlled asthmatic patient comparing with low dose ICS in step down circumstance.

Inclusion Criteria:

• Asthmatic patients who have well controlled asthma at least 12 weeks with using budesonide/formoterol (160/4.5 μg/d) twice daily
• Age more than 18 year-old
• Patients who able to do spirometry without contraindication
• History smoking less than 10 pack-years

Exclusion Criteria:

• History of using systemic steroid previous 4 week and respiratory infection
• History of pulmonary tuberculosis with residual lung lesion by chest radiograph
• recent serious medical condition such as myocardial infarction, stroke, pneumonia etc.