The aim of this study was to compare safety and efficacy of
bambuterol hydrochloride (10 mg) oral
solution administered once daily in the evening with
terbutaline sulphate (0.075 mg/kg
body weight) oral
solution administered three times daily in 2-5-year-old children with
asthma. There were two treatment groups: (2/3) of the patients received
bambuterol and (1/3) received
terbutaline. The study was double-blind, randomized, and of a parallel group design, and it lasted for 3 months after a 2-week run-in period. The primary objective was to evaluate safety (adverse events, and changes in blood pressure, pulse rate, hematology, and clinical chemistry parameters). Plasma concentrations of
terbutaline and/or
bambuterol were also measured. Evaluation of efficacy (diary card data) was a secondary objective. A total of 155 patients (range, 2-6 years; 3 patients were 6 years old at randomization) were treated with the study drugs; 104 patients received
bambuterol and 51 patients received
terbutaline. Both treatments showed a good safety profile with respect to clinical and laboratory tests, and they were generally well tolerated. Reported adverse events were mild to moderate. There were no statistically significant differences between treatment groups in any of the efficacy variables (diary variables: peak expiratory flow (PEF),
asthma symptoms,
restlessness, other reported symptoms, use of inhaled
bronchodilators, and nighttime awakenings). For morning PEF, the mean increase from run-in to treatment was 16.9 L/min in the
terbutaline group and 23.3 L/min in the
bambuterol group. For evening PEF, the mean increase was 20.2 L/min in the
terbutaline group and 20.6 L/min in the
bambuterol group. In conclusion, once-daily
bambuterol is as safe and effective as
terbutaline given three times daily. The study also confirmed that
bambuterol has a 24-hr duration of action, and therefore its once daily administration, makes it a preferred
bronchodilator agent. Pediatr Pulmonol. 2000:29:194-201.