This 12-week, double-blind, parallel-group study compared the efficacy and safety of once daily ciclesonide and twice daily fluticasone propionate in patients aged 12-75 years with persistent asthma. Patients were randomized to once-daily ciclesonide 80 micro g (n = 278) or 160 micro g (n = 271), or twice daily fluticasone propionate 88 micro g (n = 259) (all ex-actuator). Significant improvements from baseline were seen in all three treatment groups for forced expiratory volume in 1 second, asthma symptom scores and rescue medication use (all p < 0.0001). Asthma exacerbation rates were low (each ciclesonide group, n = 2; fluticasone group, n = 1). Adverse event reporting indicated good tolerability. Once daily ciclesonide 80 micro g or 160 micro g showed comparable efficacy and tolerability to twice daily fluticasone propionate 88 micro g in persistent asthma.