ABSTRACT
The pulmonary efficacy and systemic safety of inhalation drugs and consequently the degree of lung targeting are driven by drug, formulation, and device characteristics. This chapter reviews the relationship between pharmacokinetic and pharmacokinetic/pharmacodynamic factors of inhalation products and the resulting degree of pulmonary targeting. In addition, available methods ranging from cell line, isolated organs over animal models, to studies in humans are described that are able to determine and predict relevant pharmacokinetic and dynamic properties of inhalation drugs during the drug development process. Finally, in silico assessment tools including non-compartmental, compartmental, and physiologically based pharmacokinetic approaches that are able to describe and/or predict the fate of inhaled drugs in the lung and the systemic circulation are reviewed.
