In this case, bosentan was administered to patients with intermittent claudication for 12 weeks, and both the initial and four-year follow-up results indicated that bosentan treatment could be effective in improving the claudication distance, C-reactive protein (CRP) levels, and flow-mediated arterial dilation in a select group of patients with low-to-mild stages of PAD with low risk of severe adverse effects [254,255]. This evidence concerns the gene CRP and peripheral arterial disease.