A Study to Assess the Efficacy of XEN-D0501 in Reducing the Cough Frequency in Patients With COPD

The purpose of this study is to determine the effectiveness of XEN-D0501 over placebo in reducing the daytime cough frequency in patients with chronic obstructive pulmonary disease (COPD). The effectiveness of XEN-D0501 placebo in reducing capsaicin cough responses, objective 24-hour cough frequency, hourly change in cough frequency, cough severity (via visual analogue scale \[VAS\]), urge to cough (via VAS), global rating of change scale, Clinical COPD Questionnaire (CCQ), Leicester Cough Questionnaire (LCQ), and St George's Respiratory Questionnaire (SGRQ-C) will be evaluated.