Age-related Macular Degeneration (AMD) is the main cause of blindness in the western world. The macula is the central portion of the retina responsible for seeing fine details. There are two types of AMD, “wet” AMD progresses quickly but there are established treatments to help stop the patient’s vision getting worse. “Dry” AMD is slowly progressive but currently untreatable.
Now a stage I/II trial has started using a gene therapy technique to treat dry AMD. The object is to introduce a new DNA sequence to produce a protein to protect the macula from further auto-immune damage.
As some people age, genes responsible for the eye's natural defences start to malfunction and begin destroying cells in the macula, leading to vision loss.
An injection is made at the back of the eye, which delivers a harmless virus containing a synthetic gene.
The virus infects the retinal cells and releases the gene.
This enables the eye to make a protein designed to stop cells from dying and so keep the macula healthy.
The first patient was injected in January at Oxford Eye Hospital. Obviously later stage trials will need to be undertaken to demonstrate its effectiveness however if successful, it would present huge savings in health and social care costs. In the UK, where the trial is being held, there are some 600,000 patients affected by dry AMD. The hope is that in five years or so; as well as providing the minority of those with some vision with a treatment to prevent further loss, new patients will have the treatment so they experience little or no vision loss. The result will be that older people will be independent for longer, putting less demand on social care or nursing home services, costs for rehabilitating those with sight loss will plummet. So in terms of the UK, it’s win, win, win. Great for the patient, less cost for the NHS and less demand on local authorities’ social care budgets.
Similar healthcare and other savings could be made in the USA too.
- As many as 11 million people in the United States have some form of age-related macular degeneration. This number is expected to double to nearly 22 million by 2050.
- The number of people living with macular degeneration is expected to reach 196 million worldwide by 2020 and increase to 288 million by 2040.
- Age is a prominent risk factor for age-related macular degeneration. The risk of getting advanced age-related macular degeneration increases from 2% for those ages 50-59, to nearly 30% for those over the age of 75.
Given the age risk, the result would be direct government savings as most affected will be on Medicare.
The therapy was developed by Gyroscope Theraputics and further details of the therapy and trial are in the company’s press release here (.pdf)
While the prospects look very exciting, it would be irresponsible not to remind you that this is a stage I/II trial. Further clinical trials and regulatory authority for its use will take several years.