CHICAGO (Reuters) - A gene therapy treatment helped people with advanced heart failure pump blood more efficiently without causing serious side effects a year after treatment, researchers said Monday, showing yet more promise for this treatment approach.
Mydicar, a treatment made by privately held Celladon of La Jolla, California, delivers an enzyme that becomes deficient in people with advanced heart failure.
"It is found to be safe and it appears that using this therapy in patients with very advanced disease who are already getting optimal therapy can actually have an improvement in their symptoms and in their quality of life," said Dr. Donna Mancini of New York-Presbyterian Hospital/Columbia University Medical Center, who presented one-year results of the study at the American Heart Association meeting in Chicago.
And most importantly, she said it appears to prevent or delay major complications of heart disease, such as death, hospitalization or the need for a transplant.
Mancini said the study of 39 patients is the first ever of a gene therapy for the treatment of heart failure.
"What happens is there is a major defect in the calcium regulation of the cells," Mancini said in a telephone interview.
She said a gene known as SERCA2a gets turned down in people with heart failure, a chronic condition in which the heart becomes less efficient at pumping blood.
"It is important in terms of allowing the heart to relax and then trigger and contract," Mancini said.
"What this drug does is normalizes the calcium regulation in the cell."
Gene therapy -- replacing or boosting the activity of a faulty gene to correct disease -- is still considered highly experimental, although there has been some success in treating forms of blindness and immune deficiency.
With the heart failure treatment, doctors insert a catheter in heart arteries and infuse the drug near heart muscle cells.
In the study, nine patients got a high dose of the drug, eight got a low dose and eight got a mid-size dose. And 14 patients got a sham treatment.
After 12 months, patients in the high-dose treatment group had an 88 percent reduction in the risk for major complications, such as death, the need for a transplant or a heart pump, worsening of heart failure or the number of hospitalizations related to heart failure.
And it was safe, Mancini said.
"None of the patients had complications during infusion of the gene therapy. It really was very smooth and very quiet, with no signal that would indicate there was a problem," she said.
The company said the findings are strong enough to continue pursuing the treatment in a late-stage clinical trial.
Nearly 5 million Americans have heart failure, a chronic condition that costs the United States an estimated $30 billion a year to manage.