Primary To demonstrate the efficacy (non-inferiority) of Salmeterol 50mcg bid (100mcg/day), compared with Hokunalin (tulobuterol) tape 2mg once a day, in terms of improvement in pulmonary function (peak expiratory flow: PEF) in a randomized, double-blind, parallel-group comparative study in adult patients with bronchial asthma on ICS 400mcg/day of FP equivalent.