Efficacy and safety of high-dose budesonide/formoterol (Symbicort®) compared with budesonide administered either concomitantly with formoterol or alone in patients with persistent symptomatic asthma

Objective and background: Budesonide/formoterol 160/4.5 mu g, two inhalations bd, is an effective and well-tolerated maintenance therapy for patients not controlled on inhaled corticosteroids alone. The authors assessed the efficacy and safety of a higher dose of budesonide/formoterol in patients with persistent symptomatic asthma. Methods: This was a 24-week, double-blind, double-dummy randomized study. Budesonide/formoterol 320/9 mu g, two inhalations bd (1280/36 mu g/day), was compared with corresponding doses of budesonide during weeks 1-12 and budesonide plus formoterol via separate inhalers during weeks 1-24. Efficacy was assessed during weeks 1-12; the primary variable was morning PEF. Safety was assessed over weeks 1-24. Results: Patients (n = 456; aged 12-79 years) had a mean reversibility in FEV1 of 28% and mean pre-study inhaled corticosteroid dose of 1038 mu g/day. Mean morning PEF increased by 37 L/min and 36 L/min with budesonide/formoterol and budesonide plus formoterol, respectively, versus an increase of 5 L/min with budesonide (P < 0.001 for both vs. budesonide). Budesonide/formoterol increased time to first mild exacerbation (P < 0.005) versus budesonide. Budesonide/formoterol and budesonide plus formoterol had similar efficacy. All treatments were well tolerated and the incidence of class-related adverse events was similarly low in all groups. Changes in serum potassium and plasma cortisol were comparable across treatments. Conclusions: High-dose budesonide/formoterol (320/9 mu g, two inhalations bd) is effective and well tolerated in patients with persistent symptomatic asthma. The findings also support the safety of regular high-dose formoterol (36 mu g/day).