Study of Inhaled Carbon Monoxide to Treat Idiopathic Pulmonary Fibrosis

• Serum MMP7 level [ Time Frame: 3 months ] [ Designated as safety issue: No ]
  Our primary outcome is the change in MMP7 serum level over 3 months of treatment. Serum MMP7 concentrations in peripheral blood are easily measureable and reflect changes in the alveolar microenvironment. Thus, we have chosen to study mean serum MMP7 concentrations after three months of CO treatment as a surrogate biomarker of the effect of inhaled CO administration on disease progression.
  
  

• Total lung capacity (TLC) [ Time Frame: 3 months ] [ Designated as safety issue: No ]
  Total lung capacity (TLC) is a major clinical determinant of restrictive lung disease in practice, with TLC measurement below the 5th percentile of the predicted value indicative of a restrictive ventilatory defect
  
  
• Diffusing capacity for carbon monoxide [ Time Frame: 3 months ] [ Designated as safety issue: No ]
  Interstitial changes associated with IPF can worsen diffusing capabilities across the alveolar-capillary membrane. As a result, diffusing capacity of carbon monoxide is an important outcome to assess architectural distortion and resultant decrements in diffusing capabilities
  
  
• Six minute walk distance [ Time Frame: 3 months ] [ Designated as safety issue: No ]
  The six minute walk distance is commonly used both in research studies and in clinical practice as a measure of functional capabilities, and changes in six minute walk distance and oxygen use during testing over time often reflect clinically relevant disease progression. We will measure the distance travelled during six minutes (meters) in accordance with published guidelines
  
  
• St George's Respiratory Questionnaire [ Time Frame: 3 months ] [ Designated as safety issue: No ]
  St. George's Respiratory Questionnaire (SGRQ) is a validated self-reported instrument. In this instrument, scores range from 0 to 100, with higher scores reflective of worse quality of life.
  
  

Idiopathic pulmonary fibrosis (IPF) is an interstitial lung disease characterized by destruction of normal epithelial structure, proliferation of fibroblasts, and deposition of connective-tissue matrix proteins. There are currently no effective therapies for IPF. Over the past two decades, preclinical studies of inhaled low dose carbon monoxide (CO) have shown that this biologically active diatomic gas possesses properties that would make it a viable novel therapy for IPF. CO therapy has been well tolerated in Phase I and Phase II human trials to date. This phase II study is designed to investigate whether IPF patients show evidence of decreased peripheral blood levels of MMP7 and stability of secondary indicators of disease progression after 3 months of inhaled therapy.