Endothelin Receptor Antagonists: Status Quo and Future Perspectives for Targeted Therapy

The endothelin axis, recognized for its vasoconstrictive action, plays a central role in the pathology of pulmonary arterial hypertension (PAH). Treatment with approved endothelin receptor antagonists (ERAs), such as bosentan, ambrisentan, or macitentan, slow down PAH progression and relieves symptoms. Several findings have indicated that endothelin is further involved in the pathogenesis of certain other diseases, making ERAs potentially beneficial in the treatment of various conditions. In addition to PAH, this review summarizes the use and perspectives of ERAs in cancer, renal disease, fibrotic disorders, systemic scleroderma, vasospasm, and pain management. Bosentan has proven to be effective in systemic sclerosis PAH and in decreasing the development of vasospasm-related digital ulcers. The selective ERA clazosentan has been shown to be effective in preventing cerebral vasospasm and delaying ischemic neurological deficits and new infarcts. Furthermore, in the SONAR (Study Of Diabetic Nephropathy With Atrasentan) trial, the selective ERA atrasentan reduced the risk of renal events in patients with diabetes and chronic kidney disease. These data suggest atrasentan as a new therapy in the treatment of diabetic nephropathy and possibly other renal diseases. Preclinical studies regarding heart failure, cancer, and fibrotic diseases have demonstrated promising effects, but clinical trials have not yet produced measurable results. Nevertheless, the potential benefits of ERAs may not be fully realized.

Subclinical coronary artery calcification in systemic sclerosis using high-resolution chest CT: Identification, extent, and disease-specific risk factors

OBJECTIVES

Early detection of subclinical atherosclerosis is pivotal for preventing symptomatic coronary artery disease. This study aimed to compare the proportion of patients with systemic sclerosis (SSc) having an Agatston coronary artery calcification (CAC) score ≥100 using high-resolution computed tomography (HRCT) chest scans to a background population using cardiac CT scans, and to identify disease-specific risk factors for subclinical CAC in patients with SSc.

METHODS

Logistic regression models, adjusted for cardiovascular risk factors, evaluated the odds ratio of patients having a CAC score ≥100. CAC scores for the background population were derived from two cardiac CT screening cohorts. CAC scores by HRCT chest scans were calibrated using a conversion factor to adjust for overestimation in comparison to CAC scores obtained from dedicated cardiac CT scans.

RESULTS

HRCT chest scans from 394 patients with SSc were evaluated. In total, 116 (29.4 %) had a CAC score of 0, while 162 (41.1 %) had a CAC score ≥100. Disease duration (OR=1.05, 95 % CI 1.01-1.09) and a history of digital ulcers (OR=2.25, 95 % CI 1.31; 3.86) were independently associated with a CAC score ≥100. Compared to the background population, a significantly higher proportion of SSc patients had a CAC score ≥100 (35.0 % vs. 23.2 %, p<0.001).

CONCLUSION

The identification of subclinical atherosclerosis using routine HRCT chest scans in patients with SSc offers the potential to detect individuals at increased risk of developing CAD and guide preventive treatment strategies. Additionally, digital ulcers appear to be a novel risk factor for subclinical CAD in these patients.