The first ever clinical trial of a genetically-enhanced stem cell treatment for pulmonary arterial hypertension (PAH) has shown promising results, Canadian researchers report.
This rare and fatal disease is characterized by very high pressure in the arteries that supply blood to the lungs and affects mainly young women. The causes of PAH remain unknown, though in some cases it is caused by a genetic mutation. Conventional treatments can modestly improve symptoms, but cannot repair the blood vessels or cure the disease.
The trial, which results have been published in Circulation Research, was conducted to test the side effects and feasibility of a genetically-enhanced stem cell therapy to repair lung blood vessels in PAH patients. It involved seven patients, and the researchers harvested their white blood cells. These cells were then grown in the laboratory under a special regimen to turn them into endothelial progenitor cells - stem-like cells. These cells underwent genetic modification to produce greater amounts of nitric oxide which widens blood vessels and is crucial for blood vessel repair and regeneration. These cells were injected back to the patients - directly into their lung circulation.
Although the study was not designed to assess benefits of the therapy, the researchers reported improved blood flow in the patients' lungs in the subsequent days and better life quality up to six months after the treatment. However, as there was no control group in this trial, it is not possible to conclude that the effects observed were due to the stem cells treatment.
The patients tolerated the therapy well, except for one person who died the day after the treatment and whose prognosis was poor prior to treatment due to progressively declining condition.
Overall, the trial demonstrated that stem cell therapy can be beneficial for patients with pulmonary arterial hypertension, but more rigorous studies are needed to prove its efficacy.