march 2006
LCA Gene Therapy Clinical Trials Approved!
Click here to read an update on this story.
On December 13th, 2005, a team of doctors met with the National Institute of Health (NIH) to ask permission to begin clinical trials of a new gene therapy technique on humans that has the promise to cure one type of Leber's Congenital Amaurosis (LCA). Later that same month, the clinical trials were approved unanimously. Here are some details...
The Therapy
There are nine known gene mutations that cause LCA, one of which is a mutation in the RPE65 gene (which is said to cause about 6% of all known LCA cases). This defect also occurs naturally in dogs and, after years of research, doctors have developed a gene therapy technique that essentially cures these dogs of LCA. These doctors have created a virus (they call it a vector) that carries the protein that the RPE65 gene lacks. The virus is then injected directly into the retina where it sort of fills in the gaps and repairs the defective gene. This is a very simplified version of the process, of course, but that's the basic concept behind the therapy.
The success rate has been very good with dogs (and also with mice who were genetically engineered to carry the RPE65 defect). The only side effect noticed was a swelling of the eye after injection that lessened after treatment. In humans, the predicted primary side effects would be swelling, maybe some scar tissue on the eye after injection, amblyopia, and complications due to anesthesia.
After mice and dogs
Now that we have success with mice and dogs, we're ready to move on to humans! Since the retina in LCA patients degenerates over time, the doctors conducting this study have asked to perform their clinical trials on children. Their first test group will consist of three groups of three patients, ages eight to eighteen. The trials will be performed at the Children's Hospital of Philadelphia.
For more information on how the trials are progressing, read our update.
Resources
This is very exciting news! If you're interested in learning more about the clinical trials, you can watch the presentation to the NIH:
Clicking the above link will download the file directly to your computer. You'll need Real Player to view this video.
You may also want to read about the genetics behind LCA at The Foundation for Retinal Research.
Donations
Are you interested in supporting this research? You can make donations to
The Foundation for Retinal Research or The Children's Hospital of Philadelphia.