Ciclesonide is a new corticosteroid currently in clinical development for the treatment of asthma by oral inhalation. The objectives of the present study were to develop ciclesonide dry powder inhalers （DPIs, 80 μg） and investigate the anti-asthmatic effect in animals. For preparing a ciclesonide capsule-type DPI, sphere-shaped lactose was used as a diluent carrier, mixed with micronized ciclesonide, and filled into a capsule, and then put into a dry powder inhaler for oral inhalation. The asthmatic model was established with guinea pigs, and the therapeutic efficacy of ciclesonide was performed on the asthmatic guinea pig model. Results showed that the pulmonary deposition ratio of ciclesonide DPIs was approximately 26% and their content uniformity met the requirements of China Pharmacopoeia. The established pathological model exhibited the typical features of asthma with a widened pulmonary alveolar interval, narrowed alveolar space and detached bronchial mucosal epithelium with topical necrosis, goblet cell hyperplasia, and inflammatory cell infiltration. After treating with ciclesonide, the impaired indicators in asthmatic guinea pigs were significantly recovered or alleviated, exhibiting decreased total cells, decreased eosinophils and a decreased IL-5 level while there was an increased IFN-γ level in the bronchoalveolar lavage fluid （BALF）. This study develops a new pulmonary ciclesonide delivery system for treating asthma, and proves the therapeutic efficacy in asthmatic guinea pigs.
