New gene therapy may reverse heart failure

A powerful gene therapy that successfully reversed heart failure in large animal models has been developed, scientists say.
Preclinical testing, by researchers at the Cardiovascular Research Center at Icahn School of Medicine at Mount Sinai, found that SUMO-1 gene therapy shrinks an enlarged heart, improves heart function, and blood flow in animal models.
SUMO-1 is a gene that is "missing in action" in heart failure patients.
The study findings, published in the journal Science Translational Medicine, is the final study phase before human clinical trials can begin testing SUMO-1 gene therapy.
"SUMO-1 gene therapy may be one of the first treatments that can actually shrink enlarged hearts and significantly improve a damaged heart's life-sustaining function," said the study's senior investigator Roger J Hajjar, Director of the Cardiovascular Research Center at Icahn School of Medicine at Mount Sinai and the Arthur & Janet C Ross Professor of Medicine at Mount Sinai.

"We are very eager to test this gene therapy in our patients suffering from severe heart failure," he said.

When it begins, the clinical trial will be the second gene therapy treatment designed to reverse heart failure launched by Hajjar and colleagues.
The first trial, named CUPID, is in its final phases of testing SERCA2 gene therapy. Phase 1 and phase 2a trial results were positive, demonstrating substantial improvement in clinical events.
In that trial, a gene known as SERCA2 is delivered via an inert virus - a modified virus without infectious particles. SERCA2 is a gene that produces an enzyme critical to the proper pumping of calcium out of cells.

In heart failure, SERCA2 is dysfunctional, forcing the heart to work harder and in the process, to grow larger.
The virus carrying SERCA2 is delivered through the coronary arteries into the heart during a cardiac catheterisation procedure.
The new study tested delivery of SUMO-1 gene therapy alone, SERCA2 gene therapy alone, and a combination of SUMO-1 and SERCA2.
In large animal models of heart failure, the researchers found that gene therapy delivery of high dose SUMO-1 alone, as well as SUMO-1 and SERCA2 together, result in stronger heart contractions, better blood flow, and reduced heart volumes, compared to just SERCA2 gene therapy alone.