Figure 3.

The impact of different drug‐, formulation‐, and system‐specific properties on lung‐selectivity was evaluated by varying the following parameters: (a) solubility; C_s=2.5 µM (red line) and 50 µM (blue line), (b) dissociation rate; t_{½, Koff}=7.5 h (blue line) and 0.3 h (red line), (c) particle size distribution; f ₁,…,f ₈ from Table 2 (blue line) and f_i = 0.25 for i = 5, …, 8 and f_i = 0 otherwise (red line), (d) nasal absorption; nose included (blue line) and nose excluded (red line), and e) nasal absorption; nose included (blue line) and nose excluded (red line). Except for subfigure e) which shows predictions (lines) and observations (open circles) of plasma concentrations of fluticasone propionate (C_p), dashed lines represent receptor occupancy in the central lung and solid lines represent occupancy in a systemic reference organ.