tiotropium-bromide and batefenterol

GSK961081 is an inhaled bi-functional molecule with both muscarinic antagonism and β2-agonism (MABA) properties. This randomised, double-blind, double-dummy, crossover study evaluated 14 days treatment with the MABA GSK961081 400 μg and 1200 μg once daily and tiotropium 18 μg once daily plus salmeterol 50 μg twice daily (TIO + SAL), versus placebo in 50 patients with moderate COPD. The primary endpoint was forced expiratory volume in 1 s (FEV1) at 24 h on Days 1 and 14. MABA 400 (n = 29), MABA 1200 (n = 32) and TIO + SAL (n = 41) resulted in significant increases in FEV1 over 24 h. Mean (95% CI) 24 h trough FEV1 (L) values relative to placebo (n = 43) were, for Day 1, MABA 400: 0.141 (0.060, 0.222); MABA 1200: 0.184 (0.105, 0.263); TIO + SAL: 0.162 (0.092, 0.231); for Day 14, MABA 400: 0.115 (0.024, 0.205); MABA 1200: 0.168 (0.080, 0.255); TIO + SAL: 0.103 (0.026, 0.180). Onset of bronchodilation was faster for both MABA doses versus TIO + SAL. No clinically relevant systemic pharmacodynamic effects were observed. Adverse events were similar across groups; however tremor (n = 2, MABA 1200), dysgeusia (n = 2, MABA 1200; n = 2, MABA 400) and dry mouth (n = 1, MABA 1200) were reported after GSK961081 only. GSK961081 demonstrated sustained bronchodilation similar to TIO + SAL, but with a more rapid onset, and was well tolerated at the tested doses.

Topics: Adrenergic beta-2 Receptor Agonists; Adult; Aged; Albuterol; Bronchodilator Agents; Carbamates; Cross-Over Studies; Dose-Response Relationship, Drug; Double-Blind Method; Drug Therapy, Combination; Female; Forced Expiratory Volume; Humans; Male; Middle Aged; Muscarinic Antagonists; Pulmonary Disease, Chronic Obstructive; Quinolones; Salmeterol Xinafoate; Scopolamine Derivatives; Time Factors; Tiotropium Bromide; Treatment Outcome

The objective of the present studies was to characterize the pharmacologic properties of GSK-961081 [TD-5959; (R)-1-(3-((2-chloro-4-(((2-hydroxy-2-(8-hydroxy-2-oxo-1,2-dihydroquinolin-5-yl)ethyl)amino)methyl)-5-methoxyphenyl)amino)-3-oxopropyl) piperidin-4-yl [1,1'-biphenyl]-2-ylcarbamate], a novel first-in-class inhaled bifunctional compound possessing both muscarinic antagonist (MA) and β2-adrenoceptor agonist (BA) properties (MABA). In competition radioligand binding studies at human recombinant receptors, GSK-961081 displayed high affinity for hM2 (Ki = 1.4 nM), hM3 muscarinic receptors (Ki = 1.3 nM) and hβ2-adrenoceptors (Ki = 3.7 nM). GSK-961081 behaved as a potent hβ2-adrenoceptor agonist (EC50 = 0.29 nM for stimulation of cAMP levels) with 440- and 320-fold functional selectivity over hβ1- and hβ3-adrenoceptors, respectively. In guinea pig isolated tracheal tissues, GSK-961081 produced smooth muscle relaxation through MA (EC50 = 50.2 nM), BA (EC50=24.6 nM), and MABA (EC50 = 11 nM) mechanisms. In the guinea pig bronchoprotection assay, inhaled GSK-961081 produced potent, dose-dependent inhibition of bronchoconstrictor responses via MA (ED50 = 33.9 µg/ml), BA (ED50 = 14.1 µg/ml), and MABA (ED50 = 6.4 µg/ml) mechanisms. Significant bronchoprotective effects of GSK-961081 were evident in guinea pigs via MA, BA, and MABA mechanisms for up to 7 days after dosing. The lung selectivity index of GSK-961081 in guinea pigs was 55- to 110-fold greater than that of tiotropium with respect to systemic antimuscarinic antisialagogue effects and was 10-fold greater than that of salmeterol with respect to systemic β2-adrenoceptor hypotensive effects. These preclinical findings studies suggest that GSK-961081 has the potential to be a promising next-generation inhaled lung-selective bronchodilator for the treatment of airway diseases, including chronic obstructive pulmonary disease.

Topics: Adrenergic beta-2 Receptor Antagonists; Albuterol; Animals; Bronchodilator Agents; Carbamates; CHO Cells; Cricetinae; Cricetulus; Cyclic AMP; Drug Evaluation, Preclinical; Guinea Pigs; HEK293 Cells; Humans; Lung; Muscarinic Antagonists; Muscle Relaxation; Muscle, Smooth; Protein Binding; Quinolones; Receptors, Adrenergic, beta; Receptors, Muscarinic; Salmeterol Xinafoate; Scopolamine Derivatives; Tiotropium Bromide; Tissue Distribution; Trachea