Inclusion Criteria:

• Subject must have a diagnosis of COPD based on the American Thoracic Society (ATS)/European Respiratory Society (ERS) criteria.
• Subject must be >40 to <=75 years of age, of either sex, and of any race.
• Subject must be current smoker with at least 10 pack-years of smoking history (eg, 10 pack-year history is equal to smoking 1 pack of cigarettes per day for 10 years or 2 packs per day for 5 years). Subject will be counseled on the risks of smoking and available smoking cessation programs prior to enrollment. Subject who elects to continue to smoke will be eligible for enrollment. Once enrolled, if a subject elects to discontinue smoking, or reduces cigarette consumption, he/she will be allowed to complete the study.
• Subject must have a history of daily sputum production for at least the past 3 months.
• Post-bronchodilator FEV1 must be >=800 mL, and >=40% to <=70% of predicted FEV1.
• Post-bronchodilator ratio of FEV1 to forced vital capacity (FVC) must be <=70%.
• A female subject of childbearing potential must be using a medically acceptable, highly effective, adequate form of birth control (ie, failure rate less than 1% per year when used consistently and correctly) prior to Screening and agree to continue using it while in the study (Screening and Treatment Periods). Medically acceptable, highly effective forms of birth control are hormonal implants, oral contraceptives, medically acceptable prescribed intrauterine devices (IUDs), and monogamous relationship with a male partner who has had a vasectomy.

A female subject should be encouraged to continue using a highly effective method of birth control 30 days following the end of treatment.

• A female subject of child-bearing potential who is not currently sexually active must agree to use a highly effective method of contraception should she become sexually active while participating in the study.
• A male subject must agree to use an adequate form of contraception for the duration of the study and agree to have sexual relations only with women using a highly effective birth control method according to the note for guidance on non-clinical safety studies for the conduct of human clinical trials for pharmaceuticals (CPMP/ICH/286/95 mod).

A highly effective method of birth control is defined as that which results in a low failure rate (ie, less that 1% per year) when used consistently and correctly, such as hormonal implants, injectables, combined oral contraceptives, hormonal intrauterine devices (IUD).

• Female subject who is not of childbearing potential must have a medical record of being surgically sterile (eg, hysterectomy, tubal ligation), or be at least 1 year postmenopausal. Absence of menses for at least 1 year will indicate that a female is postmenopausal.
• Subject must be capable of complying with the dosing regimen and visit schedules.
• Subject must be willing to give written informed consent to participate in the study.

Exclusion Criteria:

• Subject who has been diagnosed with asthma or other clinically relevant lung disease (other than COPD), eg, sarcoidosis, tuberculosis, pulmonary fibrosis, bronchiectasis, or lung cancer.
• Subject with history of previous lung surgery (eg, lobectomy, pneumonectomy, or lung volume reduction).
• Subject who has had a lower respiratory tract infection within 4 weeks prior to the Screening Visit.
• Subject receiving chronic antibiotic therapy.
• Subject who has had an exacerbation of COPD within the 4 weeks prior to the Screening Visit.
• Subject with >20% change at Screening in post-bronchodilator FEV1.
• A female subject who is breast-feeding, pregnant, or intends to become pregnant during the study.
• Subject with clinically relevant medical conditions (eg, hematologic, cardiovascular, renal, hepatic, neurologic, or metabolic).
• Subject who has taken inhaled or systemic steroids within 4 weeks of Visit 1.
• Subject who has received an investigational drug within the last 30 days.
• Subject who produced an inadequate amount of sputum at the Screening Visit (Visit 1) or is known to have difficulty producing sputum.
• Subjects with a PBN count of <3000/micro L at the Screening Visit (Visit 1).
• Subject who is part of the staff personnel directly involved with this study.
• Subject who is a family member of the investigational study staff.
• Subject who has received any study prohibited medication more recently than the indicated washout period, prior to (Screening), or who must continue to receive any prohibited treatment.