Budesonide/formoterol for maintenance and reliever therapy of asthma: a meta analysis of randomised controlled trials

To compare the effectiveness of budesonide/formoterol (Symbicort) for Maintenance and Reliever Therapy (Symbicort SMART) Turbuhaler with twice daily inhaled corticosteroid (ICS) treatment, alone or in combination with a long-acting beta(2)-agonist (LABA).

Meta analysis of randomised controlled trials (RCTs) using a fixed effects model. RCTs were included if the comparator with budesonide/formoterol for maintenance and relief had the equivalent, or up to fourfold higher, maintenance dose of ICS. The primary outcome was the incidence of severe exacerbation (oral glucocorticosteroid treatment for > or = 3 days, emergency visit and/or hospitalisation).

Of the seven RCTs available six met the inclusion criteria. Risk of severe exacerbations was significantly reduced: 41% vs. higher-dose budesonide alone [relative risk (RR) 0.59, 95% confidence interval (95% CI): 0.51-0.68, p < 0.00001]; 43% vs. equivalent dose budesonide/formoterol as maintenance twice daily (RR 0.57, 95% CI: 0.49-0.66, p < 0.00001); 24% vs. higher-dose salmeterol/fluticasone twice daily (RR 0.76, 95% CI: 0.64-0.90, p = 0.002); and 26% vs. higher-dose budesonide/formoterol twice daily (RR 0.74, 95% CI: 0.58-0.96, p = 0.02). Significant heterogeneity was not detected in the primary analyses (p > 0.1). Secondary analyses also demonstrated that budesonide/formoterol for maintenance and relief reduced the most severe exacerbations, resulting in less hospitalisations/accident and emergency visits than higher-dose budesonide, equivalent dose budesonide/formoterol and higher-dose salmeterol/fluticasone twice daily.

Budesonide/formoterol for maintenance and relief is significantly more effective at reducing severe exacerbations than higher-dose ICS alone, or in combination with a LABA. This has important implications for treating uncontrolled patients at steps 2 and 3 of the joint BTS/SIGN guidelines.