- BACKGROUND: Ciclesonide exhibits clinical efficacy at 160 microg (ex-actuator) once daily but the anti-inflammatory effects at this dose are not known. We wished to know whether 4 weeks therapy with ciclesonide pMDI 160 microg once daily in the morning exhibited significant anti-inflammatory effects. METHODS: Seventeen patients with mild persistent asthma (FEV(1) 3.35 l) were recruited into a double-blind placebo-controlled randomized crossover study. Measurements were made after ciclesonide and placebo treatment as well as after run-in and washout periods, for adenosine monophosphate (AMP) bronchial challenge (primary variable), exhaled nitric oxide (NO) and induced sputum (in a subgroup). RESULTS: The mean (SEM) AMP bronchial challenge PC(20) following ciclesonide (140 (63) mg/ml) was significantly (P < 0.001) increased compared with placebo (17 (8) mg/ml), run-in (13 (5) mg/ml) and washout (9 (3) mg/ml) periods. This amounted to an eightfold (CI: 5.3-12.0) for ciclesonide vs placebo. Likewise, there were significant improvements in exhaled NO levels and a significant reduction in induced sputum eosinophil cell counts. CONCLUSION: We have shown that inhaled ciclesonide given at 160 microg once daily in the morning exhibits significant anti-inflammatory effects that are in keeping with the previously described clinical effects.