Imidafenacin, An Orally Active Muscarinic Receptor Antagonist, Improves Pulmonary Function In Patients With Chronic Obstructive Pulmonary Disease: A Multicenter, Randomized, Double-Blind, Placebo-Controlled 3×3 Crossover Phase II Trial

Kentaro Machida,1,* Tomotaka Kawayama,2,* Masaharu Kinoshita,3,* Masakazu Ichinose,4 Tohru Tsuda,5 Shohei Takata,6 Hiroshi Koto,7 Makoto Yoshida,8 Yoshinori Ashihara,9 Masaru Kawashima,10 Hideaki Suna,10 Hiromasa Inoue1 1Department of Pulmonary Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8520, Japan; 2Division of Respirology, Neurology, and Rheumatology, Department of Medicine, Kurume University School of Medicine, Kurume 830-0011, Japan; 3Nagata Hospital, Yanagawa 832-0059, Japan; 4Department of Respiratory Medicine, Tohoku University, Graduate School of Medicine, Sendai 980-8574, Japan; 5Kirigaoka Tsuda Hospital, Kitakyushu 802-0052 Japan; 6Division of Respiratory Medicine, National Hospital Organization Fukuoka-Higashi Medical Center, Koga 811-3195, Japan; 7Division of Respiratory Medicine, Kyushu Central Hospital of the Mutual Aid Association of Public School Teachers, Fukuoka 815-8588, Japan; 8Division of Respiratory Medicine, National Hospital Organization Fukuoka Hospital, Fukuoka 811-1394, Japan; 9Division of Respiratory Medicine, Oita Nakamura Hospital, Oita 870-0022, Japan; 10ONO Pharmaceutical Co. Ltd., Osaka 541-8564, Japan*These authors contributed equally to this workCorrespondence: Hiromasa InoueDepartment of Pulmonary Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8520, JapanTel +81 99 275 6481Fax +81 99 275 6482Email inoue-pulm@umin.netBackground: Although long-acting muscarinic receptor antagonists are central to the management of chronic obstructive pulmonary disease (COPD), inhaled medicines may have technical difficulty in some patients and adherence barriers.Methods: A multicenter, randomized, double-blind, placebo-controlled 3×3 crossover Phase II trial was performed to evaluate the efficacy and safety of oral administration of the antimuscarinic agent imidafenacin in patients with COPD. Twenty-seven male COPD patients with % forced expiratory volume in 1 s (FEV1) ≥30% and