An 80-year-old woman from the United Kingdom is the first patient to undergo gene therapy for age-related macular degeneration – the leading cause of vision loss in the world.
It is still too early to say if the procedure has been successful, reports the BBC, but for the millions of people around the world who are at risk for age-related macular degeneration or AMD, this was experimental intervention nevertheless an important medical milestone.
Oxford patient Janet Osborne has the condition in both eyes, but her left eye is more affected. The procedure for treating her AMD was performed by the Oxford University Ophthalmologist, Robert MacLaren, at the John Radcliffe Hospital in Oxford, according to a press release from the University.
Osborne struggles with day-to-day activities such as sewing, reading, and recognizing faces due to blurred vision due to their condition, the university said. She has the dry type of AMD, also known as atrophic AMD, which is more common and difficult to treat than the wet form or neovascular AMD. In the dry form, the cells in the macula – the part of the retina responsible for central vision and fine focus – gradually die and are not filled up. This results in deterioration of visibility in the form of opacities, blemishes or spots when a person is looking directly at an object while peripheral vision is not affected.
AMD is a major cause of vision loss on a global scale and, according to the US Centers for Disease Control and Prevention, is the leading cause of vision loss and blindness for Americans over the age of 65. The CDC warns that between 20 and 48 million Americans may be affected by 2050.
As reported by BBC, Osborne is the first of ten patients to be treated in the clinical trial FOCUS the use of gene therapy. The study is sponsored by the NIHR Oxford Biomedical Research Center and sponsored by Gyroscope Therapeutics, a UK company developing gene therapies for various eye diseases.
"I did not think about myself. I was thinking of other people, "Osborne was quoted as saying after her operation in the Oxford press release. "For me, I hope that my eyesight will not get worse. That would be great. That means I would not be a nuisance to my family.
Osborne was given a local anesthetic for the operation. The doctors dislodged the retina of her left eye and injected a solution containing a synthetic virus underneath (Osbourne's right eye was not treated, as this was an experimental procedure). The virus contained a modified DNA sequence, the retinal pigment epithelium (RPE), which is said to repair the genetic defect responsible for AMD, a known hereditary condition. To deliver the DNA sequence, a virus was used, which is done by infecting retinal cells.
Once the virus acts in a retinal cell, it releases the synthetic DNA and "the cell begins producing a protein that we believe can modify the disease, and corrects the imbalance of inflammation caused by the complement system "MacLaren said in the press release. The complement system is a system of proteins that fights bacteria, but in macular degeneration, this part of the immune system becomes overactive and attacks the retina cells incorrectly. The goal of the new gene therapy is to shut down the complement system, "but at a certain point at the back of the head so that the patient would otherwise be unaffected, and we hope that this will slow down the effects of macular degeneration in the future," MacLaren said
As mentioned earlier, it is still too early to say if gene therapy stopped the deterioration in Osbourne's left eye, and it will be carefully monitored over the coming weeks and months.The good news is that this gene therapy only However, it is important that this intervention is not a restorative therapy – it should stop and not reverse the degeneration caused by AMD, and ideally, this new therapy, provided it works, would be useful in patients in the early stages of AMD applied before too much retinal damage occurs.
The 13- year-old boy is the first person in the US to receive newly approved gene therapy for blindness
On Tuesday, a 13-year-old boy from New Jersey was at the center of medical history when he …
Read more Read
This is not the first gene therapy used to treat blindness. In March 2018, an FDA approved gene therapy called Luxturna was used to treat a rare hereditary form of blindness, congenital liver amaurosis.
[University of Oxford, BBC]