Navafenterol (AZD8871) in patients with COPD: a randomized, double-blind, phase I study evaluating safety and pharmacodynamics of single doses of this novel, inhaled, long-acting, dual-pharmacology bronchodilator.

Navafenterol (AZD8871) is a dual-pharmacology muscarinic antagonist β2−agonist (MABA) molecule in development for the treatment of chronic obstructive pulmonary disease (COPD). The pharmacodynamics, safety and tolerability of single doses of navafenterol were investigated in patients with moderate to severe COPD. This was a randomized, five-way complete cross-over study. Patients received single doses of navafenterol 400 μg, navafenterol 1800 μg and placebo (all double-blind) and indacaterol 150 μg and tiotropium 18 μg (both open-label active comparators). The primary pharmacodynamic endpoint was change from baseline in trough forced expiratory volume in 1 s (FEV1) on day 2. Safety and tolerability were monitored throughout. Thirty-eight patients were randomized and 28 (73.7%) completed the study. Navafenterol 400 μg and 1800 μg demonstrated statistically significant improvements vs placebo in change from baseline in trough FEV1 (least squares mean [95% confidence interval]: 0.111 [0.059, 0.163] L and 0.210 [0.156, 0.264] L, respectively, both P < .0001). The changes were significantly greater with navafenterol 1800 μg vs the active comparators (least squares mean treatment difference: 0.065–0.069 L, both P < .05). The frequency of treatment-emergent adverse events was similar for placebo and the active comparators (range 34.4–37.5%), slightly higher for navafenterol 400 μg (52.9%), and lowest for navafenterol 1800 μg (22.6%). Both doses of navafenterol demonstrated sustained bronchodilation over 24 h. Navafenterol was well tolerated and no safety concerns were raised. ClinicalTrials.gov ; No.: NCT02573155 ; URL: www.clinicaltrials.gov . Registered 9th October, 2015.