• Males are eligible to participate if they to use contraception or abstinence, and refrain from donating fresh unwashed semen during the study and for at least 30 days post-study

• Females are eligible to participate if they are not pregnant, breastfeeding and if one of the following conditions apply:

‣ Not a woman of child-bearing potential OR

⁃ Agrees to follow the contraceptive guidance and not to donate eggs for the purpose of reproduction from screening throughout the study and for at least 30 days post-study

• Current or former cigarette smokers with a history of cigarette smoking ≥ 10 pack years as of signing the ICF \[number of pack years = (number of cigarettes per day / 20) × number of years smoked (e.g., 20 cigarettes per day for 10 years, or 10 cigarettes per day for 20 years)\]. Pipe and/or cigar use cannot be used to calculate pack-year history. Former smokers are defined as those who have stopped smoking for at least 6 months prior to signing the ICF. Smoking cessation programs are permitted during the study

• Subjects with an established clinical history of COPD as defined by the American Thoracic Society (ATS)/European Respiratory Society (ERS) guidelines with symptoms compatible with COPD

• Post-bronchodilator (4 puffs of albuterol) spirometry during the Screening Period demonstrating both the following:

‣ FEV1/forced vital capacity (FVC) ratio of \< 0.70 AND

⁃ FEV1 ≥ 40 % and ≤ 80% of predicted normal

• A posterior-anterior chest x-ray (CXR) during the Screening Period or within 12 months prior to signing the ICF showing no clinically significant abnormalities unrelated to COPD. If a CXR within the past 12 months is not available but a computed tomography (CT) scan within the same time period is available, the CT scan may be reviewed in place of a CXR

• Capable of withholding from short-acting bronchodilators for at least 4 hours if using albuterol and for at least 6 hours if using ipratropium prior to pre-dose of blinded study medication spirometry testing

• Anatomical features of peripheral veins that allow the ability to draw sufficient blood volume for all study samples

• Capable of using the study supplied jet nebulizer correctly

• Ability to perform acceptable spirometry in accordance with ATS/ERS guidelines

• Willing and able to attend all study visits and adhere to all study assessments and procedures