Budesonide/formoterol (Symbicort) is well tolerated and effective in patients with moderate persistent asthma.

The aim of this study was to compare the safety and efficacy of budesonide/formoterol 160/4.5 microg, two inhalations twice daily, with that of the mono-products administered at the same daily doses via separate inhalers. A total of 586 patients (mean age 45 years) was included in this six-month, open, randomised, multicentre study. Patients received either budesonide/formoterol (n=390) or budesonide plus formoterol (n=190). Safety was assessed by adverse events, vital signs and laboratory values. Efficacy was evaluated using spirometry tests, the Mini Asthma Quality of Life Questionnaire and the Asthma Control Questionnaire. Both treatments were well tolerated, with no differences in safety parameters between the groups. Mean FEV1 increased by 5-6% over baseline in both groups. There was no significant difference in the change from baseline between the groups using the disease-specific questionnaires. Asthma exacerbations occurred with low frequency in both groups. Withdrawal rates were also comparable between the groups (p=0.085). Budesonide/formoterol in a single inhaler was as effective and as well tolerated as budesonide plus formoterol via separate inhalers.