The purpose of this study is to assess the safety and tolerability of PUR0200. In addition, the study will look at the blood levels of different doses of PUR0200 and their affect on lung function in COPD patients.

This is a multi-center, 2-part, pharmacokinetic (PK), pharmacodynamic (PD) effect, safety and tolerability study of single doses of PUR0200.

Key Inclusion Criteria:

• A clinical diagnosis of moderate to severe COPD according to the following criteria:

  • Current or ex-smokers with at least 10 pack-year smoking history
  • Post-bronchodilator FEV1 >/= 35% and </= 80% of predicted normal value
  • Post-bronchodilator FEV1/FVC (forced vital capacity) ratio <0.70
  • Post-bronchodilator improvement in FEV1 >/= 100 mL

Key Exclusion Criteria:

• Current evidence or recent history of clinically significant or unstable disease (other than COPD)
• Current diagnosis of asthma
• Presence of history of clinically significant allergy requiring treatment
• COPD exacerbation within 6 weeks
• Use of daily oxygen therapy > 10 hours
• Thoracotomy with pulmonary resection
• Use of systemic steroids within 3 months
• Lower respiratory tract infection within 30 days
• Upper respiratory tract infection within 30 days requiring treatment with antibiotics
• History of tuberculosis, bronchiectasis, or other non-specific pulmonary disease
• Prolonged corrected QT (QTc) interval >450 msec males and >470 msec females, or history of long QT syndrome