Two-Dimensional and Three-Dimensional Imaging Show Ciclesonide Has High Lung Deposition and Peripheral Distribution: A Nonrandomized Study in Healthy Volunteers

Drug deposition is an important factor that contributes to safety and efficacy outcomes of inhaled steroid therapy. Ciclesonide is a nonhalogenated, inhaled corticosteroid under investigation for the treatment of asthma. Therefore, this study was performed to assess lung deposition of ciclesonide. Technetium-^99m (^99mTc)–labeled ciclesonide (where the ^99mTc-label is physically dissolved in the ciclesonide–hydrofluoroalkane [HFA] solution aerosol) inhaled by healthy volunteers was analyzed by two-dimensional (2-D) and three-dimensional (3-D) imaging to determine lung deposition. Six healthy volunteers inhaled one puff of 40 µg (exactuator, equivalent to 50 µg ex-valve) ciclesonide for 2-D imaging, and two healthy volunteers inhaled 10 puffs of 40 µg ciclesonide for 2-D and 3-D imaging. The ciclesonide aerosol was administered via metered-dose inhaler (MDI) containing HFA-134a as propellant. The ex-actuator mean (± standard deviation) deposition of ciclesonide in the lungs was higher (52% ± 11%) than in the mouth/pharynx (38% ± 14%). Two-dimensional and 3-D imaging showed that ciclesonide reached all regions of the lung. Mean percent deposition in peripheral regions (47% and 34%) was higher than in lower central regions (17% and 30%), as revealed by 3-D and 2-D imaging, respectively. Inhalation of up to 400 µg of ciclesonide produced no drug-related side effects. In conclusion, ciclesonide administered via metered-dose inhaler using HFA-134a as a propellant provided high lung deposition (>50%), greater distribution throughout peripheral regions of the lungs, and relatively low oropharyngeal deposition.