Breathing in a New Gene Therapy to Treat Pulmonary Hypertension

Mount Sinai has partnered with Theragene Pharmaceuticals, Inc. to advance a novel airway-delivered gene therapy for treating pulmonary hypertension (PH), a form of high blood pressure in blood vessels in the lungs that is linked to heart failure. If the therapy succeeds in human clinical trials, it will provide patients for the first time with a way to reverse the damage caused by PH.

This gene therapy technique comes from the research of Roger J. Hajjar, MD, Professor of Medicine and Director of the Cardiovascular Research Center at the Icahn School of Medicine at Mount Sinai, and has been proven effective in rodent and pig animal models. PH is a deadly disease that disproportionately affects young adults and women; 58 percent of cases are found in young adults and 72 percent are women. There is currently no effective cure for PH, and about 50 percent of people who are diagnosed will die from the disease within five years.

PH is a rare (15-50 cases per million people), rapidly progressing disease that occurs when blood pressure is too high in vessels leading from the heart to the lungs. The high pressure is caused by abnormal remodeling of the lung blood vessels, characterized by a proliferation of smooth muscle cells and a thickening and narrowing of these vessels, and can lead to failure of the right ventricle of the heart and premature death. Abnormalities in calcium cycling within the vascular cells play a key role in the pathophysiology of pulmonary hypertension, along with deficiencies in the sarcoplasmic reticulum calcium ATPase pump (SERCA2a) protein which regulates intracellular calcium within these vascular cells and prevents them from proliferating within the vessel wall. Downregulation of SERCA2a leads to the proliferative remodeling of the vasculature. This gene therapy, delivered via an inhaled aerosolized spray, aims to increase the expression of SERCA2a protein, and has been shown in rodents and pigs to improve heart and lung function, as well as reduce and even reverse cellular changes caused by PH.