Reply to “Bone morphogenetic protein's contribution to pulmonary artery hypertension”

We appreciate Dr. Epstein’s raising awareness of potential complications related to the usage of recombinant Bone Morphogenetic Protein (BMP).[5] Certainly, the list of potential adverse events are concerning to numerous audiences, including dentists, oral surgeons, orthopedists, and the biomedical science community.[6] However, in addition to the well‐documented complications such as marked dysphagia, acute upper airway inflammation, and respiratory distress, Dr Epstein raises the suspicion of a possible connection between BMP usage for spine fusion and the development of pulmonary arterial hypertension (PAH). We respectfully disagree with this point of view, and wish to highlight evidence that PAH likely develops from aberrant loss‐of‐function of the BMP pathway rather than over‐activation of the BMP pathway, as would be expected if recombinant BMP were to diffuse away from a local delivery site.