TGFB1 and pulmonary arterial hypertension: In line with a prominent role of aberrant TGFβ signalling as underlying cause of PAH, the ACTR2A-Fc fusion molecule Sotatercept aims to counter this imbalance by trapping soluble TGFβ ligands (Figure 3) and thereby restoring pathogenic TGFβ signalling.8,101 Indeed, in vitro evidence shows that ACTR2A-Fc treatment of pulmonary ECs reduces pSMAD2/3 while enhances pSMAD1/5/8 signalling.