Validating a realistic physical airway model to investigate in vitro drug deposition, dissolution, and epithelial transport of orally inhaled products

Recent efforts to establish clinically appropriate in vitro test methods to study total lung deposition for orally inhaled products (OIPs) have been widely recognized. Yet, there is also increasing interest in the study of post deposition events in the lung such as particle dissolution and epithelial transport of OIPs in a clinically-relevant manner. Most of the current approaches to predict the dissolution and transport behavior of respirable-sized particles have been based on a combination of compendial impaction and dissolution methods; however, these are not surrogates of the respiratory tract and may not necessarily represent deposition patterns or absorption processes in the lung. The focus of this study is to develop and validate a realistic upper airway model by modifying the medium-sized Virginia Commonwealth University (VCU) mouth-throat (MT)
and upper trachea-bronchial (TB) model to study post-deposition events in the lung for OIPs in vitro.