jump to article
Expanding possibilities for people with vision loss  

Subscribe Now | Log In

Journal of visual impairment and blindness JVIB > News and Information > Journal of Visual Impairment & Blindness (JVIB) Breaking News From the Field > Details

First U.S. clinical trial for rare eye disease in planning stages

(Item posted 07/10/2014)

Jean Bennett, F. M. Kirby professor of ophthalmology, Perelman School of Medicine, University of Pennsylvania, recently announced plans to develop a gene therapy clinical trial to halt vision loss caused by choroideremia, a rare inherited retinal degenerative disease that affects approximately 1 in 50,000 people, most often men. It is caused by mutations to the CHM gene on the X chromosome, and there is currently no effective treatment. The first symptom of the condition is usually an impairment of night vision, which often occurs in early childhood, followed by progressive narrowing of the field of vision, as well as a decrease in the ability to see details, culminating in blindness in late adulthood.

"If this trial leads to a treatment for choroideremia, it may be possible to prevent children who are diagnosed with the condition from ever suffering the symptoms," said Dr. Bennett at a recent meeting of the Choroideremia Research Foundation (CRF) in Denver. Should it be approved, the clinical trial will take place starting in September 2014 at Children's Hospital of Philadelphia. It will likely involve nine patients, who will each receive an intraocular injection of a gene encoding a protein that their eyes should generate but do not. These injections are expected to stop the deterioration of sight. "This clinical trial means hope—a restoration of dreams, possibilities[,] and a bright future," said CRF First Vice President Beth Foss, whose father and sons have choroideremia. "When we began CRF in 2000, we knew we had to pool our resources and partner with bold researchers to find a cure."

The proposed trial is intended to complement the work of Robert MacLaren, of the Nuffield Laboratory of Ophthalmology, Oxford University, and colleagues, who used a small modified virus called AAV.REP1 to deliver the correct version of the choroideremia gene to cells in the retina of the eyes of six men. According to research MacLaren and colleagues published in the medical journal The Lancet:

The initial results of this retinal gene therapy trial are consistent with improved rod and cone function that overcome any negative effects of retinal detachment. These findings lend support to further assessment of gene therapy in the treatment of choroideremia and other diseases. . . .

In addition, Ian MacDonald of the University of Alberta plans to begin a choroideremia clinical trial later in 2014. The results of the proposed trials in the United States and Canada, and the continuing research in the United Kingdom, could ultimately effect treatments for macular degeneration, glaucoma, diabetic retinopathy, and other retinal diseases. For more information, contact: Jean Bennett, M.D., Ph.D., Perelman School of Medicine, University of Pennsylvania, 310 Stellar-Chance Labs, 422 Curie Boulevard, Philadelphia, PA 19104; website: www.med.upenn.edu. [Information for this piece was taken from the March 2014 The Lancet article, "Retinal gene therapy in patients with choroideremia: Initial findings from a phase 1/2 clinical trial," by Robert E. MacLaren et al.]

Contact: Jean Bennett, M.D., Ph.D.

URL: http://www.med.upenn.edu/apps/faculty/index.php/g275/p11214


Related Links:

Comment on JVIB Articles

Sign in to use the new comment-on-this-article feature!

Please direct your comments and suggestions to afbinfo@afb.net
Copyright © 2017 American Foundation for the Blind. All rights reserved.

  Valid HTML 4.0!