Selexipag was studied in the PGI2 Receptor Agonist In Pulmonary Arterial Hypertension (GRIPHON) trial [74], where it proved to reduce patients’ risk of death or complications related to PAH and a CTD–PAH sub-analysis confirmed those results for the 170 SSc–PAH patients involved in the trial, even though those patients were more impaired at baseline [75]. Here, PTGIR is linked to pulmonary arterial hypertension.