Symbicort pMDI provides a metered dose of 200 microgram budesonide and 6 microgram formoterol fumarate dihydrate (corresponding to delivered doses of 160 microgram and 4.5 microgram, respectively). It is indicated in adults with COPD who have a post-bronchodilator FEV1 less than 70% predicted normal and a history of exacerbations despite regular bronchodilator therapy. Two puffs are taken twice daily.
Symbicort was previously only available in the dry powder Turbohaler device.
Pre- and post-dose FEV1
A 6-month randomised, double-blind trial evaluated the effect of budesonide/formoterol pMDI on pre-dose and 1-hour post-dose FEV1 in 1704 patients with moderate to very severe COPD. Participants underwent a 2-week run-in phase and were then treated with budesonide/formoterol pMDI 160/4.5 microgram; budesonide/formoterol pMDI 80/4.5 microgram; budesonide pMDI 160 microgram plus formoterol dry powder inhaler (DPI) 4.5 microgram; budesonide pMDI 160 microgram; formoterol DPI 4.5 microgram; or placebo. All medications were given twice daily.
Improvements in pre-dose FEV1 were significantly greater in patients treated with budesonide/formoterol 160/4.5 microgram twice daily than in those who received formoterol 4.5 microgram alone (p=0.026). Significantly greater improvements were also demonstrated in 1-hour post-dose FEV1 for budesonide/formoterol 160/4.5 microgram versus budesonide 160 microgram alone (p<0.001).
Dyspnoea (assessed with breathlessness diaries) and health-related quality of life scores (based on the St George's Respiratory Questionnaire total score) were significantly improved with budesonide/formoterol 160/4.5 microgram twice daily compared with either agent alone or placebo (p≤0.044 for all).
A 12-month double-blind study (n=1964) randomised COPD patients to receive twice-daily doses of budesonide/formoterol pMDI 160/4.5 microgram, budesonide/formoterol pMDI 80/4.5 microgram, formoterol DPI 4.5 microgram, or placebo.
Patients taking budesonide/formoterol 160/4.5 microgram twice daily experienced greater improvements in pre-dose FEV1 than those taking formoterol alone (p=0.008), and greater improvements in 1-hour post-dose FEV1 than those in the placebo group (p<0.001).
Another 12-month study randomised 1219 patients to receive budesonide/formoterol pMDI 160/4.5 microgram, budesonide/formoterol pMDI 80/4.5 microgram or formoterol DPI 4.5 microgram, all taken twice daily after an initial 2-week run-in period. Exacerbations, defined as worsening of COPD requiring oral corticosteroids and/or hospitalisation, were analysed.
Compared with the formoterol group, patients in the budesonide/formoterol 160/4.5 microgram twice-daily group experienced a 34.6% reduction in exacerbation rate (p≤0.002). Budesonide/formoterol 160/4.5 microgram prolonged the time to first exacerbation compared with formoterol, corresponding to a 21.2% reduction in hazard ratio (0.788, 95% Cl 0.639–0.972; p=0.026).
When exacerbations were defined as worsening of COPD requiring oral corticosteroids, hospitalisation or antibiotic treatment, post-hoc analysis showed that rates were reduced by 25.9% with formoterol/budesonide 160/4.5 microgram twice daily versus formoterol (p≤0.023).
Studies showed that budesonide/formoterol was relatively well tolerated when administered via pMDI. Side-effects similar to those experienced after use of the individual components may occur. The most common effects are tremor and palpitations, which are usually mild and disappear within a few days.