One-year safety study with bambuterol once daily and terbutaline three times daily in 2-12-year-old children with asthma

The aim of this study was to compare bambuterol oral solution (10 mg) admin istered once daily in the evening with terbutaline oral solution (0.075 mg/ kg body weight) administered three times daily in 2-5-year-old children and to compare bambuterol tablets (10 mg or 20 mg) administered once daily in the evening with terbutaline tablets (2.5 mg) administered three times dail y in 6-12-year-old children with asthma. The study was of an open, randomiz ed, parallel-group design, and lasted 1 year. The primary objective was to evaluate safety (pulse rate, blood pressure, adverse events, hematology, an d clinical chemistry). Plasma terbutaline concentrations were also measured . Evaluation of efficacy (FEV1) was a secondary objective. A total of 141 p atients (83 boys, 58 girls) were randomized and treated with the study drug s, i.e., 43 patients in the terbutaline group (30 on oral solution and 13 o n tablets) and 98 patients in the bambuterol group (62 on oral solution and 36 on tablets). A total of 11 patients discontinued the study: 3 were on t erbutaline, and 8 were on bambuterol. There were no clinically important differences between treatment groups reg arding pulse rate, or systolic or diastolic blood pressure. There were no c linically important findings in the laboratory tests (hematology and clinic al chemistry). Both terbutaline and bambuterol were well-tolerated, and the reported adverse events were mostly mild or moderate. Mean steady state pl asma terbutaline concentrations at the visits ranged between 8.0-11.5 nmol/ L in the bambuterol tablet group and between 10.6-15.2 nmol/L in the terbut aline tablet group. The corresponding values in children on oral solution w ere 10.3-11.3 nmol/L in the bambuterol group and 7.5-9.7 nmol/L in the terb utaline group. FEV1 measured in the 6-12-year-old children increased by mor e than 0.2 L in both treatment groups during the year in the study. In conclusion, bambuterol tablets or oral solution once daily and terbutali ne tablets or oral solution three times daily showed a comparable and favor able safety profile. (C) 2000 Wiley-Liss, Inc.