As the population ages, the number of people suffering loss of vision is expected to increase. One of the largest known causes of visual disturbance is a condition known as age-related macular degeneration (AMD); an estimated one in ten people over 65 will develop this condition.
The macula is an area at the back of the eye containing photoreceptive cells that enable us to see. AMD leads to irreversible damage to these cells and, as a result, central vision is distorted, changing the shape of objects, blurring sight, or causing black spots or gaps, or is lost completely, causing blindness. It usually affects both eyes, although it may start in only one.
There are two types of AMD: wet and dry. Wet AMD occurs when abnormal blood vessels grow into the macula and leak blood and fluid, leading to scarring that causes loss of sight in the affected parts of the eye. It needs urgent treatment, as deterioration can occur quickly and is irreversible. There is no treatment for dry AMD, which develops at a slower rate.
The current form of treatment for wet AMD is through successive monthly injections of anti-VEGF drugs, which reduce new blood vessel growth or oedema (swelling), into the patient’s eyeball, and may stop or slow the development of the abnormal blood vessels. These injections can be very unpleasant for the patient but, aside from their unpleasant nature, can also cause disastrous side-effects including tearing the retina, and infections within the eye. Such injuries increase the chances of patient blindness.
Now, however, as published in Investigative Ophthalmology and Visual Science, scientists at the University of Birmingham have created a new way of administering the drug that slows the development of AMD in the form of an eye drop. This has the potential to revolutionise the treatment for wet AMD and may signal the end of painful injections.
The eye drop is made of a cell-penetrating peptide (CPP), which transmits the drug from the surface of the eye (the cornea) to the macula. The scientists involved in developing the eye-drops say that their initial lab research has produced the same results as if the drug was injected into the eye.
Arran Macleod, a solicitor in the clinical negligence team at Penningtons Manches, welcomed this development. He said: “This may have a huge impact for patients suffering from AMD. The non-invasive method of delivering the drug will be more comfortable for the patient, and will eliminate the risks associated with administering injections directly into the patient’s eye. Treating wet AMD quickly is of paramount importance, and the likely greater availability of the drug in eye drop form should help prevent delays in treatment, thus improving patient safety.”