Comparison between a new once-daily, bronchodilating drug, bambuterol, and terbutaline sustained-release, twice daily

Bambuterol is a prodrug, from which terbutaline is slowly generated. The objectives of the study were to evaluate whether bambuterol, given once daily, can control symptoms in asthmatic patients and to compare the bronchodilating effect and the side effects with those of terbutaline sustained-release (SR) tablets given twice daily. Twenty-five out-patients with bronchial asthma were treated during two consecutive 14-day periods with either 30 mg bambuterol tablets once every evening or 2 x 5 mg terbutaline SR tablets morning and evening. The study had a double-blind, cross-over and randomized design. The mean evening peak expiratory flow rate (PEFR) (i.e. 24 h after intake of bambuterol and 12 h after intake of terbutaline SR) was significantly (p less than 0.001) higher during bambuterol than during terbutaline treatment (432 vs 415 l/min). The need for beta-adrenoceptor agonist aerosol in the daytime was significantly (p less than 0.05) lower during treatment with bambuterol once daily (0.70 puffs) than with terbutaline SR b.i.d. (1.04 puffs). The type and intensity of the side effects were the same during both treatments.