Age-related macular degeneration (AMD) is a leading cause of vision loss among people aged 50 and older. While treatments for the wet form of AMD have shown promise, the dry form, which accounts for approximately 80-90% of cases, has proven more challenging to treat. However, a recent study published in The Journal of Retinal and Vitreous Disease has sparked hope for patients suffering from dry AMD.
Dry AMD is characterized by the gradual thinning of the macula, the part of the retina responsible for central vision. Over time, this thinning leads to the formation of drusen—small yellow deposits that accumulate under the retina. These deposits interfere with the macula's function, resulting in blurred or distorted vision and, eventually, a significant loss of central vision. While the disease progresses slowly, its impact on quality of life can be profound, as it affects activities that require sharp vision, such as reading, driving, and recognizing faces.
The most common approach has been the use of AREDS (Age-Related Eye Disease Study) supplements, a specific combination of vitamins and minerals that has been shown to reduce the risk of progression from early to advanced stages of AMD. However, these supplements do not reverse the damage already done or restore lost vision. For patients with wet AMD, where abnormal blood vessels grow under the retina and leak fluid or blood, treatment options like anti-VEGF injections have proven effective in improving vision. Unfortunately, until now, no such option existed for dry AMD.
The breakthrough in question is a gene therapy treatment that targets a protein called complement factor I (CFI). This protein plays a crucial role in the complement system, a part of the immune system that helps protect the eye from infection and inflammation. In people with dry AMD, the complement system is often overactive, leading to chronic inflammation that damages the macula. The gene therapy works by delivering a copy of the CFI gene directly to the retina, thereby increasing the production of the CFI protein and helping to regulate the complement system.
In a recent clinical trial, the therapy demonstrated promising results. Patients who received the gene therapy showed a statistically significant improvement in their vision compared to those who received a placebo. This is the first time that a treatment for dry AMD has not only slowed the disease's progression but also led to an actual improvement in vision. This breakthrough could represent a significant shift in how dry AMD is managed and give hope to millions of patients worldwide who currently have few options.
Dr. Richard Rosen, co-author of the study and chair of ophthalmology at the Icahn School of Medicine at Mount Sinai, highlighted the significance of this development. "This is the first therapy for dry AMD that's actually shown a benefit in improving vision," he said. "Supplements called AREDS can reduce progression, and in wet AMD we can improve vision loss with injections. But in dry AMD, none of the treatments studied in the past have improved it."Â
The implications of this advancement could lead to a broader application of gene therapy in treating other forms of retinal diseases. These findings may also encourage additional investment and research into gene therapies for a range of conditions, potentially revolutionizing how we approach the treatment of eye diseases.
Sources: The Journal of Retinal and Vitreous Diseases, MedScape