Safety, Tolerability, Pharmacokinetic and Pharmacodynamic Effects of GSK573719 (LAMA) and GW642444 (LABA)Administered Individually and Concurrently in Healthy Japanese Subjects

GW642444 is a potent and selective long-acting beta2 agonist; GSK573719 is a long-acting, inhaled, muscarinic receptor antagonist (or anticholinergic) bronchodilator. Both are in development as once daily (QD) monotherapies for the treatment of Chronic Obstructive Pulmonary Disease (COPD). Development of these two inhaled drugs as a combination therapy is also planned and would have potential for improved efficacy and patient benefit as they both work through different receptor pathways and the combined bronchodilatory effect might be additive. This study is a randomised, double blind, placebo-controlled, four-way crossover study which will assess the safety, tolerability, pharmacodynamics (PD) and pharmacokinetics (PK) of GSK573719 and GW642444 in sixteen healthy Japanese subjects. Subjects will receive four possible treatments as single inhaled doses, receiving the two monotherapies separately, the monotherapies concurrently, and placebo. Blood samples for PK analysis will be taken at regular intervals after dosing. Safety will be assessed by measurement of heart rate, blood pressure, ECG and twenty-four hour Holter monitoring, potassium, safety laboratory data and review of adverse events.