Characterizing Systemic Exposure of Inhaled Drugs: Application to the Long-Acting β2-Agonist PF-00610355

Background and Objectives PF-00610355 is an orally inhaled long-acting β2-adrenoreceptor agonist that is being developed for the once-daily treatment of chronic obstructive pulmonary disease (COPD). The pharmacological effect is exerted in the lungs. However, systemic exposure of PF-00610355 is expected to be responsible for certain drug-related adverse effects. This analysis characterizes PF-00610355 using an integrated analysis of systemic exposure, across trials and patient populations.