Open-Label, Crossover Study to Determine the Pharmacokinetics of Fluticasone Furoate and Batefenterol When...

The study aim was to investigate the pharmacokinetics of single high doses and repeated therapeutic doses of fluticasone furoate (FF) and batefenterol (BAT; a bifunctional muscarinic antagonist and β₂ -agonist) administered in combination (BAT/FF) or as monotherapy. In this open-label, 6-period, crossover study of 48 subjects, the treatment sequences were (1) single high-dose BAT/FF 900/300 μg followed by repeated therapeutic doses of BAT/FF 300/100 μg (once daily for 7 days); (2) single high-dose BAT 900 μg administered concurrently with FF 300 μg; (3) single high-dose BAT 900 μg followed by repeated therapeutic-dose BAT 300 μg; (4) single high-dose FF 300 μg followed by repeated therapeutic-dose FF 100 μg; (5) single high-dose FF 300 μg (magnesium stearate); and (6) single high-dose FF/vilanterol 300/75 μg. Plasma FF area under the plasma drug concentration-time curve (AUC) was reduced after single high-dose BAT/FF versus FF alone (ratio of geometric least squares means: 0.79; 90% confidence interval: 0.75-0.83). After repeat dosing, FF AUC at the lower therapeutic dosage was similar for BAT/FF and FF (primary endpoint; AUC geometric least squares means: 1.03). Adverse events were minor, the most common being cough. These data support the feasibility of developing BAT/inhaled corticosteroid triple therapy in a single inhaler.