Ciclesonide (Alvesco)(RPR251526) is a glucocorticoid used for the treatment of obstructive airway diseases.

Ciclesonide is effectively taken up into human alveolar type II epithelial (A549) cells and metabolized to its pharmacologically active metabolite des-CIC and fatty acid conjugates of desCIC[2].

Metabolism of ciclesonide: After initial cultivation, A549 cells are washed five times with 10 ml/dish sterile PBS. An ethanolic stock solution of ciclesonide is diluted 1000-fold with assay medium to generate the initial ciclesonide concentration. The cells are incubated for 1 h in DMEM/0.1% (w/v) BSA (5 ml/dish) containing 0.02 μM ciclesonide as described above in a CO2 incubator. At the end of the incubation period, dishes are washed five times with PBS and incubated for 3, 6, or 24 h at the same conditions in 5 ml/dish fresh medium (DMEM/0.1% (w/v) BSA). At each indicated time point, the medium is removed by aspiration, 5 mM EDTA-4Na/PBS added and dishes are incubated for further 5 min. The cells are detached from the dishes and harvested. Each dish is washed five times with icechilled PBS. (Only for Reference)