Gene therapy still benefits heart after 2 years

People with severe angina given gene therapy to improve the blood supply to the heart continue to benefit 2 years after the treatment was given, investigators report.

However, Heart Attacks, the need for surgical procedures, and deaths are more frequent during the second year, probably reflecting the severity of their underlying disease.

Dr. Richard A. Schatz, at the Scripps Clinic in La Jolla, California, and his associates previously reported favorable 1-year results in a trial that involved gene therapy for 30 patients with severe angina that was unresponsive to conventional treatment.

Specifically, DNA for a growth factor called VEGF-2 was injected into areas of the heart muscle that were being starved of blood and oxygen, with the intention of triggering the growth of new blood vessels in those regions.

In their current study, published in the Journal of Interventional Cardiology, the researchers report on 2-year outcomes.

The average angina severity decreased from 3.6 to 1.3 on a standard scoring scale after 1 year. After 2 years, the average score was still just 1.5.

During the first year, one patient had a heart attack and two underwent procedures to open clogged coronary arteries. During the second year, there were four heart attacks, five procedures, and three deaths.

"Adverse clinical events...are more frequent after the first year, and are most likely due to progression of disease ... in a high-risk population with aggressive disease," Dr. Schatz and his associates conclude.

The team notes that a large trial of VEGF-2 gene therapy is now being planned.

SOURCE: Journal of Interventional Cardiology, February 2005.