Study Of Gene Transfer For Erectile Dysfunction Shows Promise
The first human study using gene transfer to treat erectile dysfunction (ED) shows promising results and suggests the potential for using the technology to treat overactive bladder, irritable bowel syndrome and asthma, according to the researchers.
"In the small pilot study, this new therapy was well tolerated and safe," said George Christ, Ph.D., senior researcher and a professor at the Institute for Regenerative Medicine at Wake Forest University School of Medicine. "It provides evidence that gene transfer is a viable approach to treating ED and other diseases involving smooth muscle cells."
The results of the study, which included 11 men with erectile dysfunction, are reported online today in Human Gene Therapy. The technology was developed by Christ and Arnold Melman, M.D., when they worked together at Albert Einstein College of Medicine in the Bronx, New York.
Unlike traditional gene therapy, the gene transfer approach being pioneered by Christ and Melman does not change the DNA or genetic code of cells. Instead, small pieces of DNA reach the nuclei of cells and this causes them to increase production of particular proteins. These proteins help relax smooth muscle cells, the type of muscle found in the penis as well as in hollow organs such as the bladder. Relaxing the tissue allows the penis to fill with blood and become erect.
Previous research has shown that more than 50 percent of men between 40 and 70 years old and 70 percent over age 70 may have erectile dysfunction. The new therapy is a potential alternative to oral medications, such as Viagra, which are not effective for an estimated 30 to 40 percent of men with ED.
A possible advantage of gene transfer is that a single treatment could last for months. In the current study, improvements were maintained through the 24 weeks of study.
The study was conducted from May 2004 to May 2006 at Mount Sinai School of Medicine and New York University School of Medicine. Men ranged from 42 to 80 years old with a mean age of 59. Six subjects were white, four were black and one was Hispanic. In half of the subjects, the cause of