Figure 2.

Population PK model developed based on pooled data from healthy volunteers, patients with asthma and patients with COPD. Dark grey compartments represent actual compartments of the model with mass transfer. The model can be separated into the systemic disposition model (lower part, based on intravenous data of healthy volunteers), and the pulmonary absorption part (upper part, developed based on additional inhalation data). Light grey compartments represent equations to calculate input to the absorption compartments. Black boxes display the statistically significant covariates. k _a: absorption rate constant, PBIO: pulmonary bioavailable fraction, PF: proportionality factor