BMPR2 and pulmonary arterial hypertension: No current therapies target the BMPR2 pathway, even though data from a recent phase II study in modulating negative regulators of the pathway using a transforming growth factor ligand trap (sotatercept) have demonstrated proof of concept, and the unpublished phase III study in idiopathic PAH (NCT04576988) has been reported [4] as significantly achieving its primary endpoint.