Featured Research

from universities, journals, and other organizations

Clinical trial for muscular dystrophy demonstrates safety of customized gene therapy

Date:
December 1, 2011
Source:
University of North Carolina School of Medicine
Summary:
Researchers have shown that it is safe to cut and paste together different viruses in an effort to create the ultimate vehicle for gene therapy. In a phase I clinical trial, the investigators found no side effects from using a "chimeric" virus to deliver replacement genes for an essential muscle protein in patients with muscular dystrophy.

Researchers at the University of North Carolina at Chapel Hill have shown that it is safe to cut and paste together different viruses in an effort to create the ultimate vehicle for gene therapy. In a phase I clinical trial, the investigators found no side effects from using a "chimeric" virus to deliver replacement genes for an essential muscle protein in patients with muscular dystrophy.

"This trial demonstrates that gene therapy is no longer limited by the viruses we find in nature, and should usher in the next generation of viral delivery systems for human gene transfer," said senior study author R. Jude Samulski, PhD, professor of pharmacology and director of the Gene Therapy Center at UNC. The study appears online in the Nov. 8, 2011 issue of the journal Molecular Therapy.

Through gene therapy, scientists treat diseases by correcting a patient's faulty genes. Most of the time, this approach involves commandeering a natural system for infecting and introducing new genes into cells; thus, the virus. But even though there are lots of relatively innocuous viruses available for this purpose, none of them are perfectly suited for gene therapy.

Rather than rely on nature, Samulski and his colleagues decided to engineer their dream gene therapy virus in the laboratory. First they chose the adeno-associated virus or AAV, a small nonpathogenic virus that most humans are exposed to at some point in life. They then took their favorite attributes from different forms of AAV -- such as AAV type 1's ability to sneak into muscle, and AAV type 2's safe track record -- and combined them into one "chimeric" virus. In the first trial of this form of gene therapy, the investigators gave six boys with Duchenne muscular dystrophy (DMD) this new virus. An x-linked inherited disorder, DMD affects one in 4,000 newborn boys.

The virus was engineered to contain the dystrophin gene, which is missing in patients with muscular dystrophy and is the ultimate cause of the disease's progressive muscle weakness. The replacement genes were injected into the bicep in one arm and a placebo was injected into the other arm of each of the patients. The researchers were able to detect the new genes in all of the patients treated with the gene therapy, but no immunological response.

As they move on to the next phase of clinical trials, Samulski says they are carefully considering how best to administer the gene therapy vectors to patients. Delivering enough replacement genes to a therapeutic effect could require larger doses of virus, which in turn could elicit an unwanted immune response. So the researchers are exploring a number of different options, including using a new high pressure technique developed by William J. Powers, MD, professor and chair of neurology at UNC, reported last July in the same journal, to get the virus into muscle at lower doses.

Study co-authors from UNC include Dawn E. Bowles, PhD; Scott W.J. McPhee, PhD, MPH; Chengwen Li, PhD; Steven J. Gray, PhD; Jade J. Samulski, Angelique S. Camp, Juan Li, MD; Bing Wang, Paul E. Monahan, MD; Joshua C. Grieger, PhD; and Xiao Xiao, PhD.

The UNC research was funded by the National Institutes of Health, the Muscular Dystrophy Association and a grant from the Senator Paul D. Wellstone Muscular Dystropy Cooperative Research Center funded by the National Institute of Arthritis and Musculoskeletal and Skin Diseases.


Story Source:

The above story is based on materials provided by University of North Carolina School of Medicine. Note: Materials may be edited for content and length.


Journal Reference:

  1. Dawn E Bowles, Scott WJ McPhee, Chengwen Li, Steven J Gray, Jade J Samulski, Angelique S Camp, Juan Li, Bing Wang, Paul E Monahan, Joseph E Rabinowitz, Joshua C Grieger, Lakshmanan Govindasamy, Mavis Agbandje-McKenna, Xiao Xiao, R Jude Samulski. Phase 1 Gene Therapy for Duchenne Muscular Dystrophy Using a Translational Optimized AAV Vector. Molecular Therapy, 2011; DOI: 10.1038/mt.2011.237

Cite This Page:

University of North Carolina School of Medicine. "Clinical trial for muscular dystrophy demonstrates safety of customized gene therapy." ScienceDaily. ScienceDaily, 1 December 2011. <www.sciencedaily.com/releases/2011/11/111130115804.htm>.
University of North Carolina School of Medicine. (2011, December 1). Clinical trial for muscular dystrophy demonstrates safety of customized gene therapy. ScienceDaily. Retrieved April 21, 2014 from www.sciencedaily.com/releases/2011/11/111130115804.htm
University of North Carolina School of Medicine. "Clinical trial for muscular dystrophy demonstrates safety of customized gene therapy." ScienceDaily. www.sciencedaily.com/releases/2011/11/111130115804.htm (accessed April 21, 2014).

Share This



More Health & Medicine News

Monday, April 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Nine-Month-Old Baby Can't Open His Mouth

Nine-Month-Old Baby Can't Open His Mouth

Newsy (Apr. 19, 2014) Nine-month-old Wyatt Scott was born with a rare disorder called congenital trismus, which prevents him from opening his mouth. Video provided by Newsy
Powered by NewsLook.com
'Holy Grail' Of Weight Loss? New Find Could Be It

'Holy Grail' Of Weight Loss? New Find Could Be It

Newsy (Apr. 18, 2014) In a potential breakthrough for future obesity treatments, scientists have used MRI scans to pinpoint brown fat in a living adult for the first time. Video provided by Newsy
Powered by NewsLook.com
Little Progress Made In Fighting Food Poisoning, CDC Says

Little Progress Made In Fighting Food Poisoning, CDC Says

Newsy (Apr. 18, 2014) A new report shows rates of two foodborne infections increased in the U.S. in recent years, while salmonella actually dropped 9 percent. Video provided by Newsy
Powered by NewsLook.com
Scientists Create Stem Cells From Adult Skin Cells

Scientists Create Stem Cells From Adult Skin Cells

Newsy (Apr. 17, 2014) The breakthrough could mean a cure for some serious diseases and even the possibility of human cloning, but it's all still a way off. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins