AECOPD is a major cause of hospital admission and mortality. They contribute to long-term decline in lung function, physical capacity, and quality of life (QoL). RLS-0071 is a novel peptide being developed for the treatment of AECOPD. This study is designed to evaluate the safety and tolerability of RLS-0071 in the treatment of adults with moderate exacerbations of COPD.

This is a randomized, double-blind, placebo controlled trial in hospitalized participants with Acute Exacerbation of Chronic Obstructive Pulmonary Disease (AECOPD) to evaluate the safety, tolerability, preliminary efficacy, PK, and PD of RLS-0071 compared to Placebo in the treatment of AECOPD. The dosing regimen will be 3 times a day for at least 3 days and up to 5 days total if still hospitalized. Participants will be followed for efficacy and safety for 30 and 60 days after the final dose. RLS-0071 or Placebo will be given as add-on therapy to SOC management for acute exacerbations of COPD.

Inclusion Criteria:

• Hospitalized participants with a prior diagnosis of COPD including spirometry within the prior year documenting a postbronchodilator FEV1/FVC ≤ 0.7 and an FEV1

  ≤ 80%, and a clinician identified admitting diagnosis of AECOPD: acute increase in dyspnea, sputum volume or purulence - without other attributable cause.

• Participants must have a moderate exacerbation of COPD according to the Rome guidelines

• ≥ 10 pack-years smoking history.

Exclusion Criteria:

• Endotracheal intubation or mechanical ventilation.

• Participants with severe exacerbation of COPD according to the Rome guidelines

• Participants with signs and symptoms consistent with an alternative diagnosis for worsening of pulmonary status

• Interstitial lung disease.

• Current or prior history of asthma.

• Known hypersensitivity, allergy, or reaction to polyethylene glycol (PEG)

• Preexisting autoimmune disease: History of autoimmune disease and/or use of chronic steroids of >10mg/d (prednisone or equivalent) for more than 14 days prior to enrollment

• Current renal dialysis or renal dialysis planned or anticipated in the next 7 days.

• Has confounding medical conditions, including:

  1. diabetic coma,
  2. uncontrolled New York Heart Association Class IV congestive heart failure,
  3. uncontrolled angina,
  4. stroke or transient ischemic attack (TIA) within 4 weeks before study entry,
  5. clinically significant arrhythmias not controlled by medication, or
  6. idiopathic pulmonary fibrosis,

• Has a weight >120 kg at Screening.

• Known pregnancy, a positive pregnancy test at screening, or lactation for WOCBP.

• Has systemic immunosuppression/immune deficiency